RU2824182C1 - Method and apparatus for monitoring physical downlink control channel - Google Patents

Abstract

FIELD: wireless communication.

SUBSTANCE: invention relates to wireless communication, particularly to a method for monitoring a physical downlink control channel (PDCCH). Technical result is achieved by the fact that for monitoring the PDCCH, it is determined that the first monitoring capability of the terminal device is used to monitor the PDCCH of a certain set of cells of the terminal device. Cell set comprises at least two cells of the terminal device, and each cell in the cell set has the same interval pattern and the same subcarrier spacing. N non-overlapping time units of a cell set in one slot are determined, wherein the initial location of each of the N time units is based on a cell interval in the cell set and N is a positive integer. Allocating a first monitoring opportunity in a set of cells based on N time units for separate monitoring of a physical downlink control channel of each cell in the set of cells.

EFFECT: enabling monitoring of a candidate PDCCH of each cell in a set of cells with accuracy to an interval.

26 cl, 16 dwg

Description

[0001] “This application claims priority to Chinese Patent Application No. 202010280741.5, filed with the National Intellectual Property Administration of China on April 10, 2020, entitled “PHYSICAL DOWNLINK CONTROL CHANNEL MONITORING METHOD AND APPARATUS,” which is incorporated herein by reference in its entirety.”

TECHNICAL AREA

[0002] This application relates to the field of communication technologies and, in particular, to a method and apparatus for monitoring a physical downlink control channel.

LEVEL OF TECHNOLOGY

[0003] In the 5th generation (5G) mobile communication system, a network device may send data to or receive data from a terminal device via a data channel. In order for the terminal device to perform data transmission with the network device via the data channel, the network device and the terminal device need to agree on some transmission parameters for transmitting data via the data channel. For example, for downlink data transmission, the data channel may be a physical downlink shared channel (PDSCH), and control parameters for controlling data transmission on the PDSCH are transmitted via a physical downlink control channel (PDCCH). For uplink data transmission, the data channel may be a physical uplink shared channel (PUSCH), and control parameters for controlling data transmission on the PUSCH are transmitted from the network device to the terminal device via the PDCCH.

[0004] Since the terminal device does not know in advance whether the network device sends the PDCCH, the terminal device needs to monitor the PDCCH at locations where the PDCCH can be sent. These monitoring locations may also be referred to as PDCCH monitoring occasions (MOs). Such monitoring and detection performed by the terminal device on the PDCCH is also referred to as blind detection.

[0005] The 5G system introduces support for ultra-reliable and low latency communication (URLLC) services. In order to meet the low latency requirements of these services, a smaller scheduling time unit is introduced in 5G. For example, a network device may schedule a terminal device at some symbol positions in a slot instead of scheduling the terminal device only at the starting symbol of the slot. In addition, the duration of the PDSCH or PUSCH may alternatively be only a few symbols. Therefore, a concept of a PDCCH monitoring span is introduced in 5G. A terminal device monitors the PDCCH at an accuracy of the PDCCH monitoring span and monitors the PDCCH within the PDCCH monitoring span. It can be understood that one PDCCH MO is included in one PDCCH monitoring span.

[0006] In a carrier aggregation (CA) scenario, if a PDCCH or a PDCCH candidate is monitored with an accuracy of a PDCCH monitoring interval, since the configuration of the PDCCH monitoring interval of each cell depends on the configuration of the PDCCH in the bandwidth part (BWP) of the carrier, the interval patterns may differ among cells, and the locations of the starting symbols of the PDCCH monitoring intervals may also differ among cells. Therefore, the time domain locations of the PDCCH monitoring intervals of different cells may not coincide. Therefore, the PDCCH monitoring opportunity cannot be distributed among different cells with an accuracy of a PDCCH monitoring interval.

ESSENCE OF THE INVENTION

[0007] According to a first aspect, an embodiment of this application provides a method for monitoring a physical downlink control channel. The method may be performed by a terminal device or a network device, or may be performed by communication equipment, such as a chip used for the terminal device or the network device.

[0008] The method includes: determining M sets of cells, where M is a positive integer, and each of the M sets of cells includes at least one cell of the terminal device; distributing a first monitoring opportunity of the terminal device to a first set of cells based on a proportion of a number of cells included in the first set of cells in a total number of cells configured by a network device for the terminal device, wherein the first set of cells is one of the M sets of cells; and distributing, between the cells in the first set of cells, the monitoring opportunity allocated to the first set of cells for individually monitoring a physical downlink control channel of each cell in the first set of cells. The first set of cells includes one cell of the terminal device. Alternatively, the first set of cells includes at least two cells of the terminal device. Each cell in the first set of cells has the same span pattern, an aligned span location, and the same spacing between subcarriers.

[0009] At least two cells included in the first set of cells may include at least two secondary cells (SCell) of the terminal device or include a primary cell (PCell) of the terminal device and at least one SCell of the terminal device.

[0010] In a possible implementation of the first aspect, the first monitoring capability of the terminal device is determined based on a maximum number of cells supported by the terminal device for monitoring a physical downlink control channel and a monitoring capability corresponding to an interval pattern corresponding to the first set of cells.

[0011] In a possible implementation of the first aspect, the first monitoring capability includes a maximum number of times that the terminal device monitors the candidate physical downlink control channel and/or a maximum number of non-overlapping control channel elements used to monitor the candidate physical downlink control channel.

[0012] In a possible implementation of the first aspect, the maximum number of times that the terminal device monitors the candidate physical downlink control channel of the first set of cells may be obtained by calculating in accordance with the following formula:

[0013] represents the maximum number of times the terminal device monitors a candidate physical downlink control channel of the first set of cells. The subcarrier spacing of each cell in the first set of cells is configured as μs. The interval pattern is (X, Y). The value of μ is 0 or 1. The value of (X, Y) is one of the set {(2, 2), (4, 3), (7, 3)}. i is the index of the first set of cells in M sets of cells, and i is a non-negative integer less than or equal to M. represents the maximum number of cells supported by a terminal device for monitoring a physical downlink control channel. is the maximum number of times that a terminal device monitors a candidate physical downlink control channel in a certain interval of a certain cell whose subcarrier spacing is μs and whose interval pattern is (X, Y). represents the number of cells whose subcarrier spacing configured by the network device for the terminal device is μs, the slot pattern is (X, Y), and the slot locations are aligned. represents the total number of cells configured by the network device for the terminal device. j represents the subcarrier spacing configuration, and the value of j is 0 or 1.

[0014] In a possible implementation of the first aspect, the maximum value of the number of non-overlapping control channel elements that are used by the terminal device for monitoring the candidate physical downlink control channel of the first set of cells may be obtained by calculating in accordance with the following formula:

[0015] represents the maximum number of non-overlapping control channel elements used by the terminal device to monitor a candidate physical downlink control channel of the first set of cells. The subcarrier spacing of each cell in the first set of cells is configured as μs. The interval pattern is (X, Y). The value of μ is 0 or 1. The value of (X, Y) is one of the set {(2, 2), (4, 3), (7, 3)}. i represents the index of the first set of cells in the M sets of cells, and i is a non-negative integer less than or equal to M. represents the maximum number of cells supported by a terminal device for monitoring a physical downlink control channel. is the maximum number of non-overlapping control channel elements used by a terminal device to monitor a candidate physical downlink control channel in a cell interval whose subcarrier spacing is μs and whose interval pattern is (X, Y). represents the number of cells whose subcarrier spacing configured by the network device for the terminal device is μs, the slot pattern is (X, Y), and the slot locations are aligned. represents the total number of cells configured by the network device for the terminal device, j represents the subcarrier spacing configuration, and the value of j is 0 or 1.

[0016] In a possible implementation of the first aspect, each cell in the first set of cells has an aligned slot arrangement specifically includes: when the second slot overlaps the first slot, the starting symbol of the first slot is the same as the starting symbol of the second slot, and the number of symbols occupied by the first slot is the same as the number of symbols occupied by the second slot. The first slot is an slot in the first cell, and the second slot is an slot in the second cell. The first cell and the second cell belong to the first set of cells.

[0017] In a possible implementation of the first aspect, the method further includes: determining N time units of the first set of cells in one slot, where the N time units do not overlap each other, and N is a positive integer. The fact that each cell in the first set of cells has an aligned slot arrangement, in particular, includes: a third slot partially or completely overlaps the first time unit and does not overlap another time unit of N time units different from the first time unit. The third slot is an slot in a cell in the first set of cells. The first time unit is one of the N time units.

[0018] Optionally, the index of the starting symbol of the first time unit of the N time units is the smallest index in the indices of the starting symbols of all intervals in the set of cells. Optionally, the index of the starting symbol of the second time unit of the N time units is the smallest index in the indices of the starting symbols of intervals that are in all intervals in the set of cells and that do not overlap the first time unit.

[0019] According to the method for monitoring a physical downlink control channel provided in the previous aspect, cells whose intervals are not aligned are grouped into different sets of cells for differentiation, and then the monitoring capability of the PDCCH is distributed among the sets of cells by calculation using a formula or through a mapping relationship. Since the locations of the intervals of cells of a certain set of cells are aligned, this solves the problem that in a CA scenario, it is impossible to determine the monitoring capability corresponding to the interval in each cell since the intervals of different cells are not aligned, so that the terminal can monitor the physical downlink control channel with an accuracy of an interval.

[0020] According to a second aspect, an embodiment of this application provides a method for monitoring a physical downlink control channel. The method may be performed by a terminal device or a network device, or may be performed by communication equipment, such as a microcircuit used for the terminal device or the network device.

[0021] The method includes: determining that a first monitoring opportunity of a terminal device is used to monitor a physical downlink control channel of a certain set of cells of the terminal device, wherein the set of cells includes at least two cells of the terminal device, and each cell in the set of cells has the same span pattern and the same subcarrier spacing; determining N non-overlapping time units of the set of cells in one slot, wherein an initial location of each of the N time units is based on a cell span in the set of cells, and N is a positive integer; and distributing the first monitoring opportunity in the set of cells based on the N time units for individually monitoring the physical downlink control channel of each cell in the set of cells.

[0022] Optionally, the at least two cells of the terminal device include at least two SCells of the terminal device or include a primary cell PCell of the terminal device and at least one SCell of the terminal device.

[0023] In a possible implementation of the second aspect, the distribution of the first monitoring opportunity in the set of cells based on N time units includes:

when the symbols occupied by the first slot of the first cell partially or completely overlap with the first time unit, allocating part or all of the first monitoring opportunity to the first cell based on the number of all symbols occupied by the slot of the first cell. The first cell is a cell in a set of cells. The first time unit is one of the N time units.

[0024] In a possible implementation of the second aspect, distributing a first monitoring opportunity in a set of cells based on N time units includes: when symbols occupied by an interval of a second cell partially or completely overlap with a second time unit, distributing a part or all of the first monitoring opportunity to the second cell based on a ratio of the number of symbols in the overlapping part to the number of symbols occupied by the interval of the second cell. The second cell is a cell in a set of cells. The second time unit is one of the N time units.

[0025] According to the method for monitoring a physical downlink control channel provided in the above-mentioned aspects, a time unit is used as a basis for distributing a monitoring opportunity of a physical downlink channel, so as to solve the problem that in a CA scenario, a monitoring opportunity corresponding to an interval in each cell cannot be determined because the intervals of different cells are not aligned. In addition, the terminal device can monitor, with an accuracy of an interval, a candidate physical downlink control channel of each cell based on the monitoring opportunity allocated to each cell.

[0026] In a possible implementation of the first aspect or the second aspect, each interval of each cell in the set of cells is located in one of the N time units. In other words, each interval cannot cross the boundary of a time unit.

[0027] In a possible implementation of the first aspect or the second aspect, the number of consecutive symbols included in one of the N time units is the same as the minimum spacing of symbols between the starting symbols of two adjacent intervals specified by the interval template. For example, the interval template is (X, Y), and the number of consecutive symbols included in the time unit, that is, the length of the time unit, is equal to X.

[0028] In a possible implementation of the first aspect or the second aspect, when the monitoring capability is allocated to cells of a set of cells, if the set of cells includes a PCell and a SCell, the monitoring capability is preferably allocated to the PCell. In addition, if the set of cells includes only a SCell, the monitoring capability may be preferably allocated to a primary secondary cell (primary SCell).

[0029] According to a third aspect, this application further provides a communication apparatus including units or means configured to perform the steps in the first aspect or the second aspect.

[0030] According to a fourth aspect, this application further provides a communication apparatus including a processor and an interface circuit. The processor is configured to communicate with another apparatus via the interface circuit and perform the method provided in the first aspect or the second aspect. There are one or more processors.

[0031] According to a fifth aspect, this application further provides a communication apparatus including a processor configured to call a program stored in a memory to perform the method provided in the first aspect or the second aspect. The memory may be located inside or outside the apparatus. In addition, there is one or more processors.

[0032] According to a sixth aspect, this application further provides a computer program. When the program is called by the processor, the method provided in the first aspect or the second aspect is executed.

[0033] In addition, a machine-readable storage medium including the above program is provided.

BRIEF DESCRIPTION OF DRAWINGS

[0034] FIG. 1 is a schematic diagram of a communication system 100 in accordance with an embodiment of this application;

[0035] FIG. 2 is a schematic diagram of a downlink time-frequency resource grid;

[0036] FIG. 3 is a schematic diagram of the arrangement of an interval in a slot;

[0037] FIG. 4 is a schematic diagram in which the locations of intervals of different cells are aligned in a CA scenario;

[0038] FIG. 5 is a schematic diagram in which the locations of intervals of different cells are not aligned in a CA scenario;

[0039] FIG. 6 is a flow chart of a method for monitoring a PDCCH according to an embodiment of this application;

[0040] FIG. 7 is a schematic diagram of a unit of time according to an embodiment of this application;

[0041] FIG. 8 is a schematic diagram of a division of time units of a set of cells according to an embodiment of this application;

[0042] FIG. 9 is a block diagram of another method for monitoring a PDCCH according to an embodiment of this application;

[0043] FIG. 10 is a schematic representation of a cell set according to an embodiment of this application;

[0044] FIG. 11 is a schematic diagram of another set of cells according to an embodiment of this application;

[0045] FIG. 12 is a schematic diagram of another set of cells according to an embodiment of this application;

[0046] FIG. 13 is a schematic diagram of another set of cells according to an embodiment of this application;

[0047] FIG. 14 is a schematic diagram of the structure of a communication apparatus according to an embodiment of this application;

[0048] FIG. 15 is a schematic diagram of the structure of a network device according to an embodiment of this application; and

[0049] FIG. 16 is a schematic structural diagram of a terminal device according to an embodiment of this application.

DESCRIPTION OF IMPLEMENTATION OPTIONS

[0050] FIG. 1 is a schematic diagram of a communication system 100 in accordance with an embodiment of this application.

[0051] As shown in Fig. 1, the communication system 100 includes a network device 110 and a terminal device 120. The terminal device 120 communicates with the network device 110 using an electromagnetic wave. When the terminal device 120 sends information, a wireless communication module of the terminal device 120 can receive information bits that need to be sent to the network device 110 over a channel. For example, the information bits are information bits generated by a processing module of the terminal device, received from another device, or stored in a storage module of the terminal device. In particular, the terminal device 120 can be used as an entity that sends uplink data for sending an uplink channel (wherein the uplink channel can carry uplink data) to the network device 110. Of course, the terminal device 120 can also receive downlink data directly sent by the network device 110 or forwarded by a network node such as a relay device.

[0052] It should be understood that, as an example, in Fig. 1, a network device and a terminal device are shown. Optionally, the communication system 100 may include a plurality of network devices, and another number of terminal devices may be included in the coverage of each network device. This is not limited to this embodiment of this application.

[0053] In this application, the terminal device 120 may be a device of various types that provides a user with communication for transmitting voice and/or data, for example, it may be a portable device with a wireless connection function or a processing device connected to a wireless modem. The terminal device 120 may communicate with a core network via an access network, such as a radio access network, and exchange voice and/or data with the RAN. The terminal device 120 may also be referred to as a terminal, user equipment (UE), mobile station, mobile, remote station, access point (AP), remote terminal, access terminal, user terminal, user device, etc. For example, the terminal device may include a mobile phone (or called a "cellular" phone), a computer with a mobile terminal device, a portable, pocket, hand-held, computer-integrated or vehicle-mounted equipment, an intelligent wearable device, or an unmanned aerial vehicle. In this application, the chip used in the above-mentioned device may also be referred to as a terminal device.

[0054] In this application, the network device 110 may be an access network device, and the access network device may be configured to connect the terminal device 110 to an access network such as a RAN. The network device 110 may be a base station defined in the 3rd generation partnership project (3GPP), for example, may be a base station device in the LTE system, that is, an evolved NodeB (eNB/eNodeB), or may be a device on the access network side in the 5G new radio (NR) system, including a gNB and a transmission reception point (TRP), or may be a central unit (CU) or a distributed unit (DU). The CU may also be referred to as a control unit. The protocol layer of the base station is divided using the CU-DU structure. Some functions of the protocol layer are centrally managed by the CU, and some or all other functions of the protocol layer are distributed in the DU. The CU centrally manages the DU. In addition, when the eNB is connected to the 5G core network (CN), the LTE eNB may also be called an eLTE eNB. In particular, the eLTE eNB is an advanced LTE base station device based on the LTE eNB and can be directly connected to the 5G CN. The eLTE eNB also belongs to the base station device in the NR. The network device 110 may alternatively be an access point (AP), an access controller (AC), or another network device such as a relay device, a device installed on a vehicle, or an intelligent wearable device that has the ability to communicate with a terminal and a core network. The type of the network device is not limited in this embodiment of this application.

[0055] The following describes related technical features of PDCCH monitoring by a terminal device.

[0056] An NR system is used as an example. The NR system is divided into independent subcarriers in the frequency domain, and the subcarrier spacing (SCS) can be determined based on the subcarrier spacing configuration μc. For example, when μc=0, the subcarrier spacing is 15 kHz, and when μc=1, the subcarrier spacing is 30 kHz. The unit of uplink/downlink resource in the frequency domain can be a resource block (RB), and each RB includes 12 consecutive subcarriers in the frequency domain. FIG. 2 shows a downlink time-frequency resource grid. In FIG. 2, represents the number of RBs scheduled once in the downlink, and one RB includes 12 consecutive subcarriers in the frequency domain. Each element in the resource grid is called a resource element (RE). An RE represents the minimum physical resource and corresponds to one subcarrier in one symbol. The uplink time-frequency resource grid is similar to the downlink time-frequency resource grid. In the NR system, one slot includes 12 or 14 symbols in time units, and each OFDM symbol can be represented by one index. A symbol or time domain symbol in this application is an orthogonal frequency division multiplexing (OFDM) symbol.

[0057] The PDCCH is transmitted in a control-resource set (CORESET), the CORESET includes a plurality of RBs in the frequency domain and includes one symbol or several consecutive symbols in the time domain, where the symbols may be located in any positions in the slot.

[0058] A control-channel element (CCE) is a basic unit carrying a PDCCH, and each CCE in a CORESET has one corresponding sequence number. This PDCCH can be transmitted by one CCE, two CCEs, four CCEs, eight CCEs, or 16 CCEs, and the number of CCEs carrying the PDCCH can be determined based on the DCI payload size and the required coding rate. The number of CCEs carrying the PDCCH is also referred to as an aggregation level (AL). A network-side device can adjust the PDCCH aggregation level based on the state of the actual transmitted radio channel to implement adaptive transmission over the link. One CCE includes six resource-element groups (REGs). One REG occupies one OFDM symbol in the time domain and occupies one RB in the frequency domain.

[0059] The search space is a set of PDCCH candidates at the aggregation layer. A PDCCH candidate may be a PDCCH subject to blind detection or monitoring. The network device may configure for the terminal device, using higher-layer signaling such as radio resource control (RRC) signaling, a set of PDCCH candidates to be monitored. Additionally, the terminal device detects all PDCCH candidates in the search space and attempts to decode the PDCCH candidates. If the cyclic redundancy check (CRC) succeeds, the terminal device is considered to have received the PDCCH sent by the network device, and the terminal device may continue to perform subsequent related processing based on the content indicated by the PDCCH.

[0060] The meaning of "PDCCH monitoring" described in this application is the same as the meaning of "candidate PDCCH monitoring" or "candidate PDCCH monitoring". The details are not described again below.

[0061] Since the difficulty of detecting a PDCCH is relatively high, the terminal device consumes a large amount of power. Therefore, in the NR system, a monitoring capability (or called a blind detection capability) corresponding to one slot may be established to limit the power consumption when the terminal device detects a PDCCH in one slot. The monitoring capability in this application is a PDCCH monitoring capability. The monitoring capabilities corresponding to one slot may include: (1) a maximum number of times that the terminal device monitors a candidate PDCCH in one slot; and/or (2) a maximum number of non-overlapping CCEs that are used by the terminal device to monitor the PDCCH in one slot. For (1), for example, the maximum monitoring times for monitoring the PDCCH in one time interval may be the maximum monitoring times that can be performed by the terminal device in one slot. For (2), for example, a CCE may be used by the terminal device to perform channel estimation on the PDCCH. The maximum number of CCEs used by a terminal device to perform channel estimation in one slot is the maximum number of CCEs that can be used by a terminal device to perform channel estimation in one slot.

[0062] Considering that the URLLC service is defined in the NR system, in order to meet the delay requirement of the URLLC service in the NR system, a time domain unit that occupies fewer symbols than a slot, such as an interval, is introduced, which may also be called a monitoring span, a PDCCH monitoring interval, etc. For ease of description, all of them are referred to as intervals in this embodiment of this application. The terminal device can monitor the PDCCH with an interval precision, that is, use the interval as a unit for measuring the PDCCH monitoring capability of the terminal device. Similarly to the monitoring capability corresponding to a slot, one interval has a corresponding monitoring capability. The monitoring capability of an interval may include: (1) the maximum number of times that the terminal device monitors the PDCCH in one interval, which is referred to as the maximum monitoring time or the maximum number of times that the terminal device monitors the PDCCH in this embodiment of this application; and/or (2) the maximum number of non-overlapping CCEs used by the terminal device for monitoring the PDCCH in a slot is referred to as the maximum number of CCEs or the maximum number of non-overlapping CCEs for short in this embodiment of this application. The monitoring opportunity used for monitoring the PDCCH is allocated at a granularity of each slot of each serving cell of the terminal device. An slot is contained in a separate slot. The symbol spacing between two adjacent slots may cross the boundaries of two slots. Each PDCCH MO is included in one slot, and one PDCCH MO cannot cross a site boundary. The PDCCH MO may be determined jointly using an initial location for monitoring the PDCCH in one search space (SS) and a CORESET associated with the SS. For example, the division of slots in a slot may be preset by a protocol or configured by a network device using a higher-layer parameter, or the terminal device may determine the division of slots in a slot based on a preset protocol rule and a higher-layer parameter. One interval includes one or more consecutive symbols. The lengths of the intervals in one slot may be the same or different. For example, in one slot, some intervals have a length of 10 symbols each, and some intervals have a length of one or 2 symbols. FIG. 3 is a schematic diagram of the arrangement of an interval in a slot. The slot (slot 1) includes 14 symbols (from symbol 0 to symbol 13) and interval #1 to interval #3, each of which occupies three consecutive symbols.

[0063] An interval may be described using a span pattern. Typically, one span pattern may be represented by a combination of (X, Y) parameters, where X represents the minimum symbol spacing between the initial symbols of two intervals, Y represents the maximum length of a time domain of one interval or the maximum number of consecutive symbols that may be occupied by one interval. X is greater than or equal to Y. In this application, an (X, Y) span pattern may also be represented by (X, Y).

[0064] In a carrier aggregation (CA) scenario, when the CA capability supported by the terminal device exceeds four cells, the terminal device shall report to the network device the PDCCH monitoring capability in the CA scenario. For example, the CA capability supported by the terminal device is eight cells, and it is assumed that the terminal device supports monitoring a maximum of five PDCCH cells in the CA scenario, the terminal device reports to the network device that the PDCCH monitoring capability in the CA scenario is five cells. When the number of downlink cells configured by the network device exceeds the PDCCH monitoring capability supported by the terminal device in the CA scenario, the monitoring capability of each cell shall be allocated using a mapping relationship or a calculation formula. Additionally, in a self-scheduling scenario, the terminal device can monitor the PDCCH of each cell in a slot of each cell. Alternatively, in the inter-carrier scheduling scenario, the terminal device monitors the PDCCH of the primary scheduling cell in the slot of the primary scheduling cell (scheduling cel), and the PDCCH of the primary scheduling cell can be used to schedule a data channel of the primary scheduling cell, or a data channel of a scheduled cell (scheduled cell) can be scheduled. The primary scheduling cell may be a PCell, or the primary scheduling cell may be a SCell. In the inter-carrier scheduling scenario, the terminal device monitors, in the primary scheduling cell, the PDCCH based on the PDCCH configuration information of the primary scheduling cell and the PDCCH configuration information of the scheduled cell associated with the primary scheduling cell. In 3GPP Release 15, the terminal device uses one slot as the granularity of PDCCH monitoring. For example, for a cell with a subcarrier spacing of 15 kHz, the maximum number of monitoring times and the maximum number of CCEs in one slot are 44 and 56, respectively. For a cell with a subcarrier spacing of 30 kHz, the maximum number of monitoring times and the maximum number of CCEs in a slot are 36 and 56, respectively. It is assumed that the PDCCH monitoring capability supported by the terminal device in the CA scenario is four cells, and the network device configures eight downlink cells. The subcarrier spacing of two cells is 15 kHz, and the subcarrier spacing of six cells is 30 kHz. In this case, the PDCCH monitoring capability in a slot is distributed among the cells as follows.

[0065] For two downlink cells with a subcarrier spacing of 15 kHz, the maximum allocated monitoring time is calculated as follows:

[0066] represents the maximum number of times that a terminal device monitors the PDCCH in one slot of a cell whose subcarrier spacing configuration is μc=0 (i.e., the subcarrier spacing is 15 kHz) in the CA scenario. represents the maximum number of cells supported by a terminal device for monitoring PDCCH in a CA scenario. represents the maximum number of times a terminal device monitors a PDCCH in one slot of one cell whose subcarrier spacing is 15 kHz. represents the number of cells with a subcarrier spacing of 15 kHz that are configured by the network device for the terminal device. represents the total number of cells configured by the network device for the terminal device. The value of j is an integer from 0 to 3, j represents the subcarrier spacing configuration, and j has the same value as .

[0067] For two downlink cells with a subcarrier spacing of 15 kHz, the maximum number of allocated CCEs is calculated as follows:

[0068] represents the maximum number of CCEs that are used by a terminal device to monitor the PDCCH in one slot of a cell whose subcarrier spacing is 15 kHz in the CA scenario. represents the maximum number of CCEs that are used by a terminal device to monitor the PDCCH in one slot of a cell whose subcarrier spacing is 15 kHz. For the meanings of other parameters, see the above definitions. The details are not described again.

[0069] For six downlink cells with a subcarrier spacing of 30 kHz, the maximum allocated number of monitoring times is calculated as follows:

[0070] represents the maximum number of times that a terminal device monitors the PDCCH in one slot of a cell whose subcarrier spacing configuration is μc=1 (i.e., the subcarrier spacing is 30 kHz) in the CA scenario. represents the maximum number of times that a terminal device monitors the PDCCH in one slot of a cell whose subcarrier spacing is 30 kHz. For the meanings of other parameters, see the above definitions. The details are not described again.

[0071] For six downlink cells with a subcarrier spacing of 30 kHz, the maximum number of CCEs allocated to each cell is calculated as follows:

[0072] represents the maximum number of CCEs that are used by a terminal device to monitor PDCCH in one cell slot with a subcarrier spacing of 30 kHz in the CA scenario. represents the maximum number of CCEs that are used by a terminal device to monitor the PDCCH in one slot of a cell whose subcarrier spacing is 30 kHz. For the meanings of other parameters, see the above definitions. The details are not described again.

[0073] FIG. 4 is a schematic diagram in which the slot locations of different cells are aligned in a CA scenario. In FIG. 4, CC #1 to CC #8 represent eight downlink cells configured by a network device for a terminal device. Although the subcarrier spacing configurations of the eight downlink cells may be different, the slot boundaries are determined. In other words, the slot boundaries of cells with the same subcarrier spacing are aligned, and the boundaries of cells with different subcarrier spacings are aligned by integer multiples. The starting position of a slot in a cell with a subcarrier spacing of 30 kHz may be in a middle position or may be aligned with a slot in a cell with a subcarrier spacing of 15 kHz. In the slot area, the maximum number of CCEs with monitoring allocated to six cells with a subcarrier spacing of 30 kHz shown in the grid is 108, and the maximum number of CCEs is 168. In the slot area, a maximum of 44 CCEs and 56 CCEs are allocated to two cells with a subcarrier spacing of 15 kHz shown by a slash. Specifically, for two cells with a subcarrier spacing of 15 kHz, the maximum number of PDCCHs with monitoring for 1 ms is 44, and the maximum number of CCEs is 56. For six cells with a subcarrier spacing of 30 kHz, a maximum of 108 PDCCHs can be monitored for 0.5 ms and a maximum of 168 CCEs can be monitored.

[0074] In the CA scenario, when the terminal device monitors the PDCCH with slot granularity, since the slot configuration of each cell depends on the PDCCH configuration on the BWP of the carrier, the slot patterns of different cells may be different, and the locations of the starting symbol of the slots in different cells may also be different. In other words, the locations of the slots in the time domain between different cells may be not-aligned. In addition, when the PDCCH monitoring opportunity is allocated between different cells with slot granularity, for slots that partially overlap and are not aligned, it is unclear whether these slots need to participate in the allocation of the PDCCH monitoring opportunities for the symbols that do not overlap each other. As a result, the PDCCH monitoring opportunity cannot be allocated for the slot of each cell. FIG. 5 is a schematic diagram in which the slot locations of different cells are not aligned in a CA scenario. In FIG. 5, CC #1 and CC #2 represent one cell, and the interval patterns corresponding to CC #1 and CC #2 are both (4, 3).

[0075] Therefore, this application proposes a method for monitoring a PDCCH to determine a monitoring capability corresponding to a cell interval of a terminal device in a CA scenario, so that the terminal device monitors a PDCCH in each cell of the terminal device with an accuracy of an interval.

[0076] FIG. 6 is a flow chart of a method for monitoring a PDCCH according to an embodiment of this application. The method presented in this application may be performed by a terminal device or a network device, or may be performed by communication equipment such as a chip used for a terminal device, or may be performed by communication equipment such as a chip used for a network device.

[0077] As shown in Fig. 6, the method includes the following steps.

[0078] Step S601: Determine that the first monitoring opportunity of the terminal device is used to monitor the PDCCH of a set of cells of the terminal device, wherein the set of cells includes at least two cells of the terminal device, and each cell in the set of cells has the same interval pattern and the same subcarrier spacing.

[0079] It can be understood that the PDCCH is an example of a downlink control channel of the physical layer. In different systems, the downlink control channel may have different names. This is not limited in this application. In this application, the PDCCH is used as an example for description.

[0080] In this application, monitoring the PDCCH of a set of cells by a terminal device may mean that the terminal device monitors candidate PDCCHs of all cells in the set of cells. In particular, if the self-scheduling method is used, the terminal device monitors separately, in each cell in the set of cells, the PDCCH sent by the cell. If the inter-carrier scheduling method is used, the terminal device monitors the PDCCH of the primary scheduling cell in the set of cells, and the PDCCH of the primary scheduling cell may be used to schedule a data channel of the primary scheduling cell or may schedule a data channel of a scheduled cell. In the self-scheduling scenario, the PDCCH of the cell refers to a PDCCH that is sent by the cell and that is used to schedule the data channel of the cell. In the inter-carrier scheduling scenario, the PDCCH of the cell refers to a PDCCH for scheduling the data channel of the cell. If the cell is the primary scheduling cell, the PDCCH is sent in the primary scheduling cell. If the cell is a scheduled cell, the PDCCH is sent in the primary scheduling cell that schedules the scheduled cell. In the inter-carrier scheduling scenario, the terminal device may monitor, in the primary scheduling cell, the PDCCH based on the PDCCH configuration information of the primary scheduling cell and the PDCCH configuration information of the scheduled cell associated with the primary scheduling cell.

[0081] In this application, a cell of a terminal device may be a serving cell that establishes a wireless connection with the terminal device, and the terminal device may perform wireless communication with the cell.

[0082] At least two cells included in the set of cells may include at least two SCells of the terminal device or include a Pcell of the terminal device and at least one SCell of the terminal device. In particular, the network device may configure one PCell and at least one SCell for the terminal device in order to implement communication between the network device and the terminal device in a CA method. The PCell and the SCell may have the same subcarrier spacing or different subcarrier spacing. The SCell may be a PSCell or include a PSCell and another secondary cell other than the PSCell, and there is only one PSCell. It should be noted that the cell (PCell or SCell) described in this application is a downlink cell, and "cell" is directly used for the description in the following.

[0083] For example, a method for determining a set of cells is described as follows: it is assumed that a PCell and SCell #1 with a subcarrier spacing of 15 kHz, and SCell #2 and SCell #3 with a subcarrier spacing of 30 kHz are configured for a terminal device. The slot pattern for the PCell is (4, 3), the slot pattern for SCell #1 is (4, 3), the slot pattern for SCell #2 is (2, 2), and the slot pattern for SCell #3 is (2, 2). Since the PCell and SCell #1 have the same subcarrier spacing and the same slot pattern, the PCell and SCell #1 are grouped into one set of cells. Since SCell #2 and SCell #3 have the same subcarrier spacing and the same slot pattern, SCell #2 and SCell #3 are grouped into another set of cells.

[0084] Optionally, the first monitoring opportunity includes a maximum number of monitoring times and/or a maximum number of CCEs.

[0085] Optionally, in an implementation of this application, determining a first monitoring capability of the terminal device includes: determining a first monitoring capability of the terminal device based on a total capability value that corresponds to a cell set interval pattern and that relates to the terminal device and that supports PDCCH monitoring, and a proportion (ratio) of the number of cells in the cell set to the total number of cells configured by the network device for the terminal device. Optionally, the total capability value of performing PDCCH monitoring by the terminal device is determined based on a maximum number of cells supported by the terminal device for performing PDCCH monitoring in a CA scenario and the monitoring capability corresponding to the cell set interval pattern. It can be understood that the maximum number of cells supported by PDCCH monitoring performed by the terminal device is less than the total number of cells configured by the network device for the terminal device. If the total number of cells configured by the network device for the terminal device is equal to the number of cells supported by the terminal device for performing PDCCH monitoring, it indicates that the capability of the terminal device can support PDCCH monitoring of all the cells configured for the terminal device, and the allocation of the monitoring capability is not involved.

[0086] Optionally, in the implementation of this application, the maximum number of monitoring times in the first monitoring opportunity is calculated in accordance with the following formula (1):

formula (1)

[0087] represents the maximum number of times that the terminal device monitors the PDCCH of a cell set. The subcarrier spacing of each cell in the cell set is configured as μc. The slot pattern is (X, Y). The value of μc is 0 or 1. μc=0 indicates that the subcarrier spacing is 15 kHz, and μc=1 indicates that the subcarrier spacing is 30 kHz. The value of (X, Y) is one of the set {(2, 2), (4, 3), (7, 3)}. represents the maximum number of cells supported by a terminal device for monitoring PDCCH in a CA scenario. represents the maximum number of times that a terminal device monitors the PDCCH in a cell interval whose subcarrier spacing is configured as μs and whose interval pattern is (X, Y). represents the number of cells whose subcarrier spacing configured by the network device for the terminal device is μ and the interval pattern is (X, Y), i.e. represents the number of cells in the set hundredths. represents the total number of cells configured by the network device for the terminal device. The value of j is 0 or 1, j represents the subcarrier spacing configuration, and j has the same value as .

[0088] Optionally, in the implementation of this application, the maximum number of CCEs in the first monitoring opportunity is calculated according to the following formula (2):

formula (2)

[0089] represents the maximum number of CCEs used by a terminal device to monitor the PDCCH in a set of cells. represents the maximum number of CCEs used by a terminal device to monitor the PDCCH in one slot of a cell whose subcarrier spacing is configured as μ and whose slot pattern is (X, Y). The physical meanings of the variables with the same names in Formula (2) and Formula (1) are the same, and the details are not described again.

[0090] For example, the network configuration configures a total of five cells for a terminal device: PCell, SCell #1, and SCell #2, whose subcarrier spacing is 15 kHz, and SCell #3 and SCell #4, whose subcarrier spacing is 30 kHz. The interval patterns for PCell and SCell #1 are (4, 3). The interval pattern of SCell #2 is (2, 2). The interval patterns of SCell #3 and SCell #4 are (7, 3). PCell and SCell #1 belong to cell set 1 of cell set 1, and SCell #3 and SCell #4 belong to cell set 2 of cell set. It is assumed that the terminal device supports a maximum of four cells to monitor on the PDCCH in the CA scenario, the maximum number of times of monitoring the (4, 3) slot pattern corresponding to a cell with a subcarrier spacing of 15 kHz is 44, and the maximum number of times of monitoring the (7, 3) slot pattern corresponding to a cell with a subcarrier spacing of 30 kHz is 36. The maximum number of times of monitoring a set of 1 cells calculated by formula (1). The maximum number of times of monitoring a set of 2 cells is calculated according to the formula (1). In other words, in the CA scenario, in a cell whose subcarrier spacing is 15 kHz and whose slot pattern is (4, 3), the total number of times of PDCCH monitoring at the slot granularity does not exceed 70. In a cell whose subcarrier spacing is 30 kHz and whose slot pattern is (7, 3), the total number of times of PDCCH monitoring at the slot granularity does not exceed 57. The method for calculating the maximum number of CCEs is similar, and the details are not described again.

[0091] It can be understood that the above-mentioned formulas (1)-(2) can also be used to calculate the maximum number of monitoring times/maximum number of CCs corresponding to SCell #2. However, since SCell #2 does not belong to a cell set, or SCell #2 is used independently as a cell set, for SCell #2, monitoring capabilities do not need to be distributed among different cells in the cell set using the method described in subsequent steps S202-S203.

[0092] Step S602: Determine N time units of a set of cells in one slot, wherein the initial location of each of the N time units is based on a cell interval in the set of cells, and N is a positive integer.

[0093] A time unit may also be referred to as a time window or symbol set and includes a group of consecutive time domain symbols.

[0094] That the N time units do not overlap each other includes: the time domain symbols included in any two of the N time units do not overlap at all. In other words, the locations of any two of the N time units do not overlap at all.

[0095] Optionally, in an implementation of this application, the index of the starting symbol of the first time unit in the N time units is the smallest index in the indices of the starting symbols of all intervals in the set of cells.

[0096] In particular, the first time unit may be the first time unit that appears in the slot, that is, the first time unit in the first slot. The location of the starting symbol of the first time unit is based on the interval with the lowest index in the indices of the starting symbols of all intervals in the set of cells. In particular, the location of the earliest interval (called below the "first interval") in all intervals is determined, and the index of the starting symbol of the first time unit is the same as the index of the starting symbol of the first interval.

[0097] Optionally, in an implementation of this application, the location of a time unit other than the first time unit in the N units is determined based on an index of a starting symbol of an interval that is in all intervals in the set of cells and that does not overlap an adjacent time unit before said time unit. Non-overlapping means that the occupied symbols do not overlap at all. For example, the second time unit is determined as a time unit adjacent to the first time unit, and the second time unit is after the first time unit. The index of the starting symbol of the second time unit is the smallest index in the indices of starting symbols of intervals that are in all intervals in the set of cells and do not overlap with the first time unit. In another example, the third time unit is determined as a time unit adjacent to the second time unit, and the third time unit is after the first time unit and the second time unit. The index of the starting symbol of the third time unit is the smallest index among the indices of the starting symbols of the intervals that do not overlap the second time unit and are in all the intervals in the set of cells except for the interval included in the first time unit. According to this rule, the location of the starting symbol of each of the remaining N time units can be determined. The details are not described again. It can be understood that since the N time units do not overlap with each other, only the interval that occurs after the previous time unit adjacent to the time unit can be considered for determining the location of the starting symbol of the time unit other than the first time unit. If an interval occurs before the adjacent previous time unit, even if this interval does not overlap the adjacent previous time unit, this interval is not taken into account for determining the location of the starting symbol of said time unit. For example, in the above-mentioned process of determining the location of the starting symbol of the third time unit, even if the first interval does not overlap the second time interval, since the first interval is before the second time unit, the first interval is not taken into account. It should also be noted that "before" and "after" in this application represent a sequence of occurrence in a time sequence and can be determined using the index value of the starting symbol of a time unit or interval.

[0098] Optionally, in an implementation of this application, the network device pre-configures that each interval of each cell in the set of cells is located in one time unit of N time units. In other words, one interval cannot cross the boundaries of two or more time units. The complexity of calculating the monitoring capability corresponding to the interval can be reduced. In another implementation, the location of the interval of another cell may not be limited. One interval of any cell in the set of cells may be located in two or more time units, that is, it may cross the boundaries of two or more time units. Alternatively, part of the symbols of the interval are in one time unit, and the remaining part of the symbols are outside the time unit, but the remaining symbols do not belong to another time unit. In this implementation, the configuration of the interval is very flexible and can be applied to various communication scenarios. In the following implementations, an unlimited location of the interval is used for description.

[0099] Optionally, in an implementation of this application, the number of consecutive symbols included in one of the N time units is the same as the minimum spacing of symbols between the starting symbols of two adjacent intervals specified by the interval pattern. In particular, as described above, the interval pattern can be represented as (X, Y). In this case, the number of consecutive symbols included in the time unit, or the length of the time unit, is X symbols.

[00100] Optionally, the lengths of the N time units may be the same, for example, all the lengths are X symbols. In a possible scenario, the time unit whose start symbol index is the largest of the N time units, that is, the last time unit in the interval, may cross the boundaries of two slots. For example, as shown in FIG. 7, the slot occupies 14 symbols from symbol 0 to symbol 13. The cell interval pattern is (4, 3). The location of the first interval in the slot is symbol 1, symbol 2, and symbol 3. The location of the second interval is symbol 5, symbol 6, and symbol 7. The location of the third interval is symbol 11, symbol 12, and symbol 13. In this implementation, the location of the time unit (time unit #3) determined based on the third interval is symbol 11, symbol 12, symbol 13, and symbol 0 of the next slot in the current slot. In other words, time unit #3 crosses the slot boundary.

[00101] Optionally, some of the N time units have different lengths. For example, it may be restricted that the last time unit in one slot does not cross the boundaries of two slots. In other words, the length of the last time unit is restricted by the boundary of the slot in which the last time unit is located, and the length of the last time unit may be less than X. In other words, the length of the last time unit is equal to the minimum value of the number of symbol spacings between the starting symbol of the last time unit and the slot boundary and X. As shown in FIG. 7, the length of the time unit (time unit #3’) determined based on the interval is equal to X, and the minimum value between the starting symbol of the third interval and the number of symbols at the boundary of the current slot, that is, min{4, 13-11+1}=3. In this case, the location of the time unit #3” is symbol 11, symbol 12 and symbol 13 of the current slot, and it does not extend beyond the slot boundary.

[00102] Referring to Fig. 8, the relationship between a time unit and an interval of each cell of a set of cells is described. The set of cells shown in Fig. 8 includes a PCell and a SCell. The subcarrier spacing of both the PCell and the SCell is 15 kHz. The interval patterns of both the PCell and the SCell are (4, 3). The length of each interval in a PCell or SCell is three symbols. The minimum symbol spacing between two intervals in the same cell is four symbols. PCell has interval #1, interval #2, and interval #3 in slot 1. SCell has interval #4, interval #5, and interval #6 in slot 1. Slot 1 includes 14 symbols (from symbol 0 to symbol 13) whose index numbers are from 0 to 13. For PCell, the starting symbol location of interval #1 is symbol 0, and interval #1 occupies symbol 0 to symbol 2. The spacing between the starting symbol location of interval #2 and the starting symbol location of interval #1 is four symbols. Slot #2 occupies symbols 4 to 6. The spacing between the starting symbol location of section #3 and the starting symbol location of interval #2 is five symbols. Interval #3 spans characters 9 through 11. For SCell, the starting character location of interval #4 is character 2, and interval #4 spans character 2 through 4. The spacing between the starting character locations of interval #5 and interval #4 is four characters. Interval #5 spans characters 6 through 8. The spacing between the starting character locations of interval #6 and interval #5 is four characters. Interval #6 spans characters 10 through 12.

[00103] As shown in Fig. 8, interval #1 is an interval with the smallest index of the starting symbol in all intervals. Therefore, the location of the starting symbol of interval #1 can be used as the location of the starting symbol of time unit #1. Interval #2 has the smallest index of the starting symbol in all intervals that do not overlap time unit #1. Therefore, the location of the starting symbol of interval #2 can be used as the location of the starting symbol of time unit #2. Interval #3 has the smallest index of the starting symbol in all intervals (except interval #1) that do not overlap time unit #2. Therefore, the location of the starting symbol of interval #3 can be used as the location of the starting symbol of time unit #3. In addition, the lengths from time unit #1 to time unit #3 are equal to X in the interval pattern corresponding to the set of cells, that is, four symbols. Therefore, the time unit #1 occupies from symbol 0 to symbol 3, and the time unit #2 occupies from symbol 4 to symbol 7. The time unit #3 occupies symbols 9 to 12 (the shaded frame in Fig. 8 represents the time unit). As shown in Fig. 8, the symbols occupied by the interval #1-interval #3 are respectively located in the time unit #1 to the time unit #3. Some of the symbols occupied by the interval #4 are in the time unit #1, and some of the symbols are in the time unit #2 (partially overlapping the time unit #1 and the time unit #2). Some of the symbols occupied by the interval #5 are in the time unit #2 (partially overlapping the time unit #2). The symbols occupied by the interval #6 are located in the time unit #3.

[00104] Step S603: allocate a first monitoring opportunity in a set of cells based on N time units to separately monitor the PDCCH of each cell in the set of cells.

[00105] Specifically, since N time units are set, the first monitoring opportunity is allocated among the cells in the cell set using the time unit as the unit. In other words, the first monitoring opportunity is considered to be allocated to each cell in each time unit. In addition, the monitoring opportunity of each cell is embodied in an interval unit in one slot. In other words, the first monitoring opportunity is finally allocated to the interval of each cell in each time unit. In addition, the terminal device monitors the candidate PDCCH of each cell in the cell set with an interval accuracy. Optionally, the value , calculated in accordance with the above formula (1), or the value , calculated according to the above formula (2), can be used for distribution between intervals in one of the N time units.

[00106] Optionally, the terminal device or the network device determines, based on the overlap state between the symbol occupied by the cell interval in the set of cells and one or more time units, how to participate in the distribution of the first monitoring opportunity in each time unit.

[00107] In an implementation of this application, when the symbols occupied by a first slot of a first cell partially or completely overlap with a first time unit, a portion or all of the first monitoring opportunity is allocated to the first cell based on the number of all symbols occupied by the slot of the first cell. The first cell is a cell in a set of cells. The first time unit is one of the N time units.

[00108] FIG. 8 is used as an example. When a monitoring opportunity is allocated to an interval of each cell in a time unit #1, because the interval #1 is completely located in the time unit #1, and a part of the interval #4 is located in the time unit #1, the number of all symbols occupied by each of the interval #1 and the interval #4 is used to participate in the allocation of the first monitoring opportunity in the time unit #1.

[00109] When a monitoring opportunity is allocated to an interval of each cell in a time unit #2, since the interval #2 is completely located in the time unit #2, the interval #4 is partially located in the time unit #2, and the interval #5 is partially located in the time unit #2, the number of all symbols respectively occupied by the interval #1, the interval #2, and the interval #3 participates in the allocation of the first monitoring opportunity in the time unit #1.

[00110] The following describes the distribution of monitoring capabilities between intervals per unit of time.

[00111] FIG. 8 is still used as an example. It is assumed that the PDCCH monitoring capability (using the maximum number of CCEs as an example) allocated to a set of 1 cells is , that is, the maximum number of CCEs allocated for each time unit of 1 cell set is 40. In addition, the sum of the maximum numbers of CCEs used for monitoring the PDCCH in intervals of different cells in each time unit of 1 cell set is 40. Since a part of interval #4 is located in time unit #1, in a possible implementation, interval #4 is completely taken into account in time unit #1. Therefore, the sum of the maximum numbers of CCEs corresponding to interval #1 and interval #4 is 40. In addition, the 3GPP protocol provides that the PDCCH overbooking scenario appears only in PCell. In the overbooking scenario, a terminal device may perform PDCCH dropping so that the maximum monitoring time and the maximum number of CCEs, which are used by the terminal device for monitoring the PDCCH, do not exceed the maximum upper limit, respectively. In this application, the maximum upper limit is that one gap pattern in one slot is the maximum number of monitoring times and the maximum number of CCEs corresponding to the gap whose gap pattern is (X, Y). It is assumed that the maximum number of CCEs corresponding to the gap with the gap pattern (4, 3) is 36, and the sum of the maximum numbers of CCEs used by the PCell and the SCell of cell set 1 to monitor the PDCCH with the gap accuracy is 40. Since the terminal device needs to perform PDCCH discarding on the PCell, the network device first determines that the maximum number of CCEs configured in one slot of the gap pattern (4, 3) in the PCell of the terminal device does not exceed 36. In other words, in unit time #1, the maximum number of CCEs configured in the gap #1 does not exceed 36. The remaining part is 40-36=4. Therefore, the maximum number of CCEs configured by the network device for slot #4 in time unit #1 in the SCell does not exceed 4. Optionally, if all cells of the cell set are SCell cells, since the terminal device does not need to perform PDCCH discarding, the network device only needs to set that the sum of the maximum numbers of CCEs configured in slot #1 and slot #4 in time unit #1 does not exceed 40. The maximum number of CCEs separately received by slot #1 and slot #4 may be arbitrarily distributed by the network device.

[00112] In an implementation of this application, when the symbols occupied by the interval of a second cell partially or completely overlap with a second time unit, based on a proportion of the number of symbols of the overlapping portion in the number of symbols occupied by the interval of the second cell, a part or all of the first monitoring opportunity is allocated to the interval of the second cell. The second cell is a cell in a set of cells. The second time unit is one of the N time units.

[00113] FIG. 8 is used as an example. When a monitoring opportunity is allocated to a slot of each cell in a time unit #1, the slot #1 is completely located in the time unit #1, that is, the ratio of overlapping symbols between the slot #1 and the time unit #1 is 100%. The slot #4 overlaps two symbols with the time unit #1, the length of the slot #4 is three symbols, and the overlap ratio is 2/3. Therefore, the slot #1 participates in the allocation of the first monitoring opportunity in the time unit #1 by using 100% of the number of symbols occupied by the slot #1. In addition, the slot #4 participates in the allocation of the first monitoring opportunity in the time unit #1 by using 2/3 of the number of symbols occupied by the slot #4.

[00114] When a monitoring opportunity is allocated to a slot of each cell in a time unit #2, slot #2 is completely located in time unit #2. Slot #4 overlaps with time unit #1 by one symbol, the length of slot #4 is three symbols, and the overlap ratio is 1/3. Slot #5 and time unit #2 overlap by two symbols, the length of slot #5 is three symbols, and the overlap ratio is 2/3. Therefore, slot #2 participates in the allocation of the first monitoring opportunity in time unit #2 by using 100% of the number of symbols occupied by slot #2. Slot #4 participates in the allocation of the first monitoring opportunity in time unit #2 by using 1/3 of the number of symbols occupied by slot #4. Slot #5 participates in the allocation of the first monitoring opportunity in time unit #2 by using 2/3 of the number of symbols occupied by slot #5.

[00115] Optionally, in an implementation of this application, when a symbol occupied by a first cell interval spans two time units, the first cell interval participates in the assignment of a first monitoring opportunity in only one of the two time units.

[00116] FIG. 8 is used as an example. Optionally, if interval #4 participates in the distribution of the first monitoring opportunity in unit of time #1 using all symbols, interval #4 no longer participates in the distribution of the first monitoring opportunity in unit of time #2. In other words, the interval participates in the distribution of the first monitoring opportunity in the previous unit of time that overlaps the interval. Optionally, if interval #4 participates in the distribution of the first monitoring opportunity in unit of time #2 using all symbols, interval #4 no longer participates in the distribution of the first monitoring opportunity in unit of time #1. In other words, the interval participates in the distribution of the first monitoring opportunity in the next unit of time that overlaps the interval. It is not necessary that if the interval # 4 participates, in the ratio of overlapping symbols, in the distribution of the first monitoring opportunity in the unit of time that overlaps the interval # 4, since the number of overlapping symbols between the interval # 4 and the unit of time # 1 is 2, the number of overlapping symbols is greater than the number (1) of overlapping symbols between the interval # 4 and the unit of time # 2, the interval # 4 can only participate in the distribution of the first monitoring opportunity in the unit of time # 1 and does not participate in the distribution of the unit of time # 2. In other words, one interval participates in the distribution of monitoring opportunities in the unit of time in which the ratio of overlapping symbols with the interval is the highest.

[00117] It can be understood that an interval related to a unit of time participates in the distribution of monitoring opportunities for each cell in a unit of time, and the interval related to a unit of time includes at least one interval whose symbol overlaps the unit of time.

[00118] In the implementation of this application, when the above-described method is performed by a terminal device, after the terminal device allocates the first monitoring opportunity in a set of cells according to steps S601 to S603, the terminal device can monitor the PDCCH with an interval granularity based on the monitoring opportunity of the interval allocated to the cell. For example, in a self-scheduling scenario, the terminal device monitors separately, with an interval granularity of each cell, the PDCCH sent in the cell. In a multi-carrier scheduling scenario, the terminal device monitors the PDCCH of the primary scheduling cell with an interval granularity of the primary scheduling cell. The PDCCH of the primary scheduling cell can be used for scheduling a data channel of the primary scheduling cell or a data channel of a scheduled cell. A PCell can be used as the primary scheduling cell of a certain SCell, or an SCell can be used as the primary scheduling cell of another SCell.

[00119] In an implementation of this application, when the above-mentioned method is performed by a network device such as a base station, after the base station allocates the first monitoring opportunity in a set of cells according to steps S601-S603, the base station may send PDCCH configuration information to the terminal device.

[00120] According to the PDCCH monitoring method provided in this application, one or more time units are set for a set of cells including cells with the same subcarrier spacing and the same interval pattern. Based on an overlapping relationship between the time unit and the time domain location of an interval of each cell in the set of cells, a monitoring opportunity corresponding to the set of cells is allocated between the cells. In this way, in the CA scenario, a problem is solved in that the monitoring opportunity corresponding to an interval in each cell cannot be determined since the intervals of different cells are not aligned. In addition, the terminal device can monitor a candidate PDCCH of each cell with an accuracy of an interval based on the monitoring opportunity of the interval allocated to each cell.

[00121] FIG. 9 is a flow chart of a method for monitoring a PDCCH according to an embodiment of this application. The method presented in this application may be performed by a terminal device or a network device, or may be performed by communication equipment such as a chip used for a terminal device, or may be performed by communication equipment such as a chip used for a network device.

[00122] As shown in Fig. 9, the method includes the following steps.

[00123] Step S901: Determine M sets of cells, where M is a positive integer, and each of the M sets of cells includes at least one cell of the terminal device.

[00124] Step S902: allocate a first monitoring opportunity of the terminal device to a first set of cells based on a proportion of the number of cells included in the first set of cells in the total number of cells configured by the network device for the terminal device, wherein the first set of cells is one of M sets of cells.

[00125] The first set of cells is one of the M sets of cells.

[00126] Optionally, in an implementation of this application, the first set of cells includes one cell of the terminal device.

[00127] Optionally, in an implementation of this application, the first set of cells includes at least two cells of the terminal device. Each cell in the first set of cells has the same span pattern, an aligned span location, and the same subcarrier spacing. That is, for each set of cells in the M sets of cells, each cell included in the set of cells has the same span pattern, an aligned span location, and the same subcarrier spacing.

[00128] Optionally, the set of cells includes at least two SCells of a terminal device or includes a PCell of a terminal device and at least one SCell of a terminal device.

[00129] For a description of the interval pattern and subcarrier spacing, see the above-mentioned related content. The details are not described again.

[00130] Optionally, each cell in the first set of cells has an aligned slot arrangement, including: when the second slot overlaps the first slot, the starting symbol of the first slot is the same as the starting symbol of the second slot, and the number of symbols occupied by the first slot is the same as the number of symbols occupied by the second slot. The first slot is an slot in the first cell, and the second slot is an slot in the second cell. The first cell and the second cell belong to the first set of cells. In particular, the first slot may be any slot in the first cell. The second slot may be any slot in the second cell. The first cell and the second cell may be any two cells that are configured by the network side for the terminal device and that have the same slot pattern and the same subcarrier spacing. In this implementation, the requirement for aligning the slot arrangement is that a plurality of slots that separately belong to a plurality of cells and whose locations in the time domain overlap have the same starting symbols. In other words, the indices of the starting symbols are the same and the lengths of the slots are the same. If the starting symbols of the slots of two cells are different, it cannot be considered that the slot locations of the two cells are aligned. In this application, the previously described case in which the slot location of each cell in the first cell set is aligned may be referred to as a scenario in which the slots of the first cell set are completely aligned. As shown in FIG. 10, the cell set includes a PCell and a SCell, both of which have coverage patterns of (4, 3). Slot #1, slot #2, and slot #3 are configured for the PCell in one slot. Slot #4, slot #5, and slot #6 are configured for the SCell in one slot. The lengths from slot #1 to slot #6 are all three symbols. The starting symbols of slot #1 and slot #4 are the same. The starting symbols of slot #2 and slot #5 are the same. The starting symbols of slot #3 and slot #6 are the same. Therefore, it can be considered that the locations of the PCell and SCell intervals are aligned.

[00131] Optionally, in an implementation of this application, the method further includes: determining N time units that belong to the first set of cells and that do not overlap with each other in one slot, wherein N is a positive integer. The value of the time unit is the same as the value of the time unit in the embodiments described in Fig. 6 to Fig. 8. For how to determine the time unit, refer to the preceding related content, such as the related descriptions in step S602. The details are not described again.

[00132] In this implementation, whether the starting symbols of the cell intervals in a set of cells are the same is not limited.

[00133] In this implementation, the fact that each cell in the first set of cells has an aligned slot location includes, in particular: a third slot partially or completely overlaps the first time unit and does not overlap another time unit of N time units different from the first time unit. The third slot is an slot in the first set of cells. The first time unit is one of the N time units. In other words, any slot in the first set of cells is completely located in one of the N time units. Alternatively, a part of the slot is in the time unit, and the remaining part is outside the time unit and is not in another time unit. In other words, the slot does not cross the boundary of two time units. The fact that the slot is partially or completely located in the time unit means that the symbols occupied by the slot may be partially or completely located in the time unit. In other words, the symbols occupied by the slot may partially or completely overlap the symbols occupied by the time unit. In this application, the above case in which the location of an interval of each cell in the first set of cells is aligned may be referred to as a scenario in which intervals in the first set of cells are aligned based on time units.

[00134] Optionally, the above two methods for determining that the locations of an interval are aligned may be used in combination. For example, the starting symbols of the first intervals of the first cell and the second cell in the same slot are the same and have the same length, and the starting symbols of other intervals after the first interval are different, but are located in the same time unit. It is also possible to consider that the locations of these cells are aligned.

[00135] Optionally, in an implementation of this application, some or all of the M sets of cells may include only one cell. The cell may be a PCell or an SCell of a terminal device.

[00136] With reference to FIG. 11, a method for determining the above-mentioned M sets of cells is described. It is assumed that a network device configures five cells for a terminal device, one of the cells is used as a PCell of the terminal device, and the remaining cells are used as SCell #1 to SCell #4 of the terminal device. The subcarrier spacing of the PCell, SCell #1, SCell #2, SCell #3, and SCell #4 is all 15 kHz. The interval patterns for the PCell, SCell #1, and SCell #2 are (4, 3). The interval patterns of SCell #3 and SCell #4 are (7, 3). PCell has slot #1, slot #2, and slot #3 in slot 1. SCell #1 has slot #4, slot #5, and slot #6 in slot 1. SCell #2 has slot #7, slot #8, and slot #9 in slot 1. SCell #3 has slot #10 and slot #11 in slot 1. SCell #4 has slot #12 and slot #13 in slot 1. Slot 1 includes 14 symbols (from symbol 0 to symbol 13), whose ordinal numbers are from 0 to 13. For PCell, the starting symbol location of slot #1 is symbol 0, and slot #1 occupies symbol 0 to symbol 2. The separation between the starting symbol location of slot #2 and the starting symbol location of slot #1 is four symbols. Interval #2 occupies characters 4 through 6. The interval between the starting character location of interval #3 and the starting character location of interval #2 is five characters. Interval #3 occupies characters 9 through 11. For SCell #1, the starting character of interval #4 is character 2, and interval #4 occupies character 2 through character 4. The spacing between the starting character locations of interval #5 and interval #4 is four characters. Interval #5 occupies characters 6 through 8. The interval between the starting character locations of interval #6 and interval #5 is four characters. Interval #6 occupies characters 10 through 12. For SCell #2, the starting character of interval #7 is character 2, and interval #7 occupies character 2 through character 4. The spacing between the starting character locations of interval #8 and interval #7 is four characters. Interval #8 extends from symbol 6 to symbol 8. The spacing between the starting symbol locations of interval #9 and interval #8 is four symbols. Interval #9 extends from symbols 10 to 12. For SCell #3, the starting symbol of interval #10 is symbol 0, and interval #10 extends from symbols 0 to symbol 2. The spacing between the starting symbol locations of interval #11 and interval #10 is seven symbols. Interval #11 extends from symbols 7 to 9. For SCell #4, the starting symbol of interval #11 is symbol 4, and interval #12 extends from symbols 4 to 6. The spacing between the starting symbol locations of interval #13 and interval #12 is seven symbols. Interval #13 extends from symbols 11 to 13. As shown in Fig. 11, the subcarrier spacing configurations and slot patterns of PCell, SCell #1, and SCell #2 are the same, but the slots are not aligned. PCell is separately allocated to a set of cells (cell set 1). SCell #1 and SCell #2 have the same subcarrier spacing and the same slot pattern, and the slots are aligned. Therefore, SCell #1 and SCell #2 can be divided into a set of cells (cell set 2). Although PCell, SCell #3, and SCell #4 have the same subcarrier spacing and the same slot pattern, the slots are not aligned. Therefore, they are independent cell sets (from 3-cell set to 4-cell set).

[00137] It is not necessarily considered that the time unit is used as a basis for defining a cell set. Since the slot patterns and subcarrier spacings of the PCell, SCell #1, and SCell #2 are the same, the time unit can be first defined based on the slots of the PCell, SCell #1, and SCell #. 2. As shown in FIG. 12, the time units #1 to the time unit #3 are included, and the length of each time unit is four symbols (one dotted rectangle in FIG. 12 represents one time unit). A part of the symbols of the slot #4 and the slot #7 are located in the time unit #1. A part of the symbols of the slot #5 and the slot #8 are located in the time unit #2. A part of the symbols of the slot #6 and the slot #9 are located in the time unit #3. Therefore, the PCell can be used, and the SCell #1 and SCell #2 are grouped into a cell set (cell set 1'). The length of the time unit #4 and the length of the time unit #5 are seven symbols. Since all symbols of interval #10 and interval #12 are located in time unit #4, and all symbols of interval #11 and interval #13 are located in time unit #5, SCell #3 and SCell #4 are grouped into a cell set (cell set 2’).

[00138] The maximum number of cells supported by the PDCCH monitoring performed by the terminal device is the maximum total number of cells of all subcarrier spacings supported by the PDCCH monitoring performed by the terminal device under the CA condition. In addition, the total number of cells does not depend on the subcarrier spacing configurations of different cells, that is, it includes the total number of cells with different subcarrier spacings configured by the network device.

[00139] Optionally, the first monitoring opportunity includes a maximum number of monitoring times and/or a maximum number of CCEs. See the relevant descriptions above. The details are not described again.

[00140] Optionally, in an implementation of this application, the first monitoring opportunity of the terminal device is determined based on a maximum number of cells supported by PDCCH monitoring performed by the terminal device and a monitoring opportunity corresponding to an interval pattern of the first set of cells.

[00141] Optionally, in an implementation of this application, the maximum number of monitoring times allocated to the first set of cells may be calculated in accordance with the following formula (3):

(3)

[00142] represents the maximum number of times the terminal device monitors the PDCCH in the first cell set. The subcarrier spacing of each cell in the first cell set is configured as μ. The interval pattern is (X, Y). The value of μ is 0 or 1. The value of (X, Y) is one of the set {(2, 2), (4, 3), (7, 3)}. The first cell set is represented by the set i of cells, i is the index of the first cell set in M cell sets, and i is a non-negative integer less than or equal to M. represents the maximum number of cells supported by PDCCH monitoring by the terminal device. represents the maximum number of times that a terminal device monitors the PDCCH in a cell slot whose subcarrier spacing is μ and whose slot pattern is (X, Y). represents the number of cells whose subcarrier spacing is μ, the slot pattern is (X, Y), and the slot locations are aligned, configured by the network device to the terminal device, that is, represents the number of cells in the first set of cells or the set of i cells. represents the total number of cells configured by the network device for the terminal device. j represents the subcarrier spacing configuration, and the value of j is 0 or 1.

[00143] Optionally, i may be counted starting from 0, or may be counted starting from 1.

[00144] Optionally, in an implementation of this application, the maximum number of CCEs allocated to the first set of cells may be calculated in accordance with the following formula (4):

(4)

[00145] represents the maximum number of CCEs used by the terminal device for monitoring the PDCCH in the first set of cells. represents the maximum number of CCEs used by the terminal device to monitor the PDCCH in a cell slot, the subcarrier spacing configuration is μ, and the slot pattern is (X, Y). The variables with the same name in Formula (4) and Formula (3) have the same physical meaning, and the details are not described again.

[00146] It can be understood that, since the terminal device monitors the PDCCH with interval granularity, in a scenario in which the intervals in the first set of cells are completely aligned, the monitoring capability allocated to the first set of cells may be the sum of the monitoring capabilities of all the cells in the first set of cells in the time domain range of one interval. In a scenario in which the intervals in the first set of cells are aligned based on time units, the monitoring capability allocated to the first set of cells may be the sum of the monitoring capabilities of all the cells in the first set of cells in the time domain range of a time unit. For example, the above refers to the sum of the maximum numbers of times that the terminal device monitors candidate PDCCHs of all cells in the first set of cells in the time domain range of an interval or time unit. As another example, the above refers to the sum of the maximum numbers of CCEs used by the terminal device for monitoring candidate PDCCHs of all cells in the first set of cells in the range of the time domain of an interval or time unit.

[00147] Step S903: Distribute the monitoring opportunity allocated to the first set of cells among the cells in the first set of cells to separately monitor the PDCCH of each cell in the first set of cells.

[00148] Optionally, the distribution among the cells in the first set of cells of the monitoring opportunity distributed to the first set of cells satisfies the following condition: the sum of the maximum number of times of monitoring distributed to all cells is less than or equal to the maximum number of times of monitoring distributed to the first set of cells; and the sum of the maximum number of CCEs distributed to the cells is less than or equal to the maximum number of CCEs distributed to the first set of cells.

[00149] Optionally, when a time unit is used as a basis for determining a set of cells, and a monitoring opportunity allocated to the set of cells is allocated among cells in the set of cells, an overlap between an interval and a time unit of each cell may be considered, and the monitoring opportunity is allocated among cells using the overlap relationship between the interval and the time unit. For a specific implementation, refer to the relevant content shown in Fig. 6 to Fig. 8, for example, the description of step S603. The details are not described again.

[00150] Optionally, distributing between cells in a first set of cells the monitoring capability allocated to the first set of cells includes: when the first set of cells includes a PCell and a SCell, preferentially distributing the monitoring capability to the PCell. Similarly, when a SCell includes a PSCell, the priority of distributing the monitoring capability to the PSCell is higher than that of the other SCell.

[00151] Fig. 13 describes a process for calculating the monitoring capability of a set of cells.

[00152] It is assumed that the network side configures eight cells for the terminal device (in Fig. 13, CC#1 to CC#8 are used to represent the eight cells). The cells with a subcarrier spacing of 15 kHz are CC#1 and CC#2, and the cells with a subcarrier spacing of 30 kHz are CC#3, CC#4, CC#5, CC#6, CC#7, and CC#8. The slot pattern of CC#1 is (2, 2), the slot patterns of CC#2 to CC#6 are (4, 3), and the slot patterns of CC#7 and CC#8 are (7, 3). Each of CC#1, CC#2, CC#3, CC#7, and CC#8 is a cell set, and CC#4, CC#5, and CC#6 are grouped into a cell set. For the method for determining the cell set, see the preceding content. The details are not described again. The superscripts (X, Y) in Fig. 13 indicate whether the patterns are the same. For example, (4, 3)’ and (4, 3)’ have the same subcarrier spacing configurations, the same slot patterns, and aligned cell intervals. (7,3)’ and (7,3)” have the same subcarrier spacing configurations, the same slot patterns, but the cell intervals are not aligned. It is assumed that the relationship between the serving cell whose slot pattern is (X, Y) and the subcarrier spacing is μ, the maximum number of monitoring times for a terminal device to monitor an alternative PDCCH, and the maximum number of usable CCEs are shown in Table 1 to Table 2.

[00153] It is assumed that the PDCCH monitoring capability supported by the terminal device in the CA scenario is four cells. The maximum number of CCEs is used as an example below:

for a set of 1 cell, i.e. CC #1,

for a set of 2 cells, i.e. CC #2,

for a set of 3 cells, i.e. CC #3,

for a set of 4 cells, i.e. CC #4, CC #5 and CC #6,

for a set of 5 cells, i.e. CC #7,

for a set of 6 cells, i.e. CC #8,

[00154] The calculation of the maximum number of monitoring times is similar and is not described here.

[00155] It can be understood that the calculation formulas presented in this application are merely examples and do not constitute a limitation for this application. For example, the calculation formulas may have a variation delay, and the names of the variables used in the calculation formulas may also be replaced.

[00156] According to the PDCCH monitoring method presented in this application, cells with the same subcarrier spacing, the same slot pattern, and aligned slot locations are grouped into a cell set. The monitoring capability of the terminal device is allocated to the cell set based on a proportion of the number of cells included in the cell set in the total number of cells configured by the network device for the terminal device. The monitoring capabilities are allocated to the cells in the cell set. Cells with unaligned slots are grouped into different cell sets for differentiation, and then the PDCCH monitoring capability is allocated to the cell sets by calculating according to a formula or by means of a mapping relationship. This eliminates the problem in the CA scenario since the slots of different cells are not aligned and it is impossible to determine the monitoring capability corresponding to the slot of each cell. In addition, the terminal device can monitor a candidate PDCCH of each cell in the cell set with slot accuracy based on the monitoring capabilities of the slot allocated to each cell.

[00157] An embodiment of this application further provides a communication apparatus configured to implement any of the above-mentioned methods. For example, a communication apparatus is provided that includes units (or means) configured to implement the steps performed by a terminal device or a network device in any of the above-mentioned methods. For example, Fig. 14 is a schematic diagram of a communication apparatus according to an embodiment of this application. The communication apparatus may be a module, such as a chip, used for a terminal device or a network device. Alternatively, the communication apparatus is a terminal device or a network device. As shown in Fig. 14, the communication apparatus 1400 includes a determining unit 1410 and a distributing unit 1420.

[00158] Optionally, in an implementation, determining unit 1410 may be configured to: determine that the first monitoring opportunity of the terminal device is used to monitor the PDCCH of a set of cells of the terminal device, wherein the set of cells includes at least two SCells of the terminal device or includes a PCell of the terminal device and at least one SCell of the terminal device, and each cell in the set of cells has the same interval pattern and the same subcarrier spacing; and determine N time units of the set of cells in one slot, wherein the starting location of each of the N time units is based on an interval of a cell in the set of cells, and N is a positive integer. Allocating unit 1420 may be configured to allocate the first monitoring opportunity in the set of cells based on the N time units for individually monitoring the PDCCH of each cell in the set of cells.

[00159] For more detailed descriptions of the determining unit 1410 and the distributing unit 1420 in this implementation, refer directly to the corresponding descriptions in the method shown in Fig. 6 to Fig. 7. The details are not described again.

[00160] Optionally, in an implementation, the determining unit 1410 may be configured to determine M sets of cells, where M is a positive integer, and each of the M sets of cells includes at least one cell of the terminal device. The allocating unit 1720 is configured to allocate a first monitoring opportunity of the terminal device to a first set of cells based on a proportion of a number of cells included in the first set of cells in a total number of cells configured by the network device for the terminal device, and to allocate, between the cells in the first set of cells, the monitoring opportunity allocated to the first set of cells for individually monitoring a PDCCH of each cell in the first set of cells. The first set of cells is one of the M sets of cells. The first set of cells includes one cell of the terminal device. Alternatively, the first set of cells includes at least two cells of the terminal device. Each cell in the first set of cells has the same span pattern, an aligned span location, and the same subcarrier spacing. At least two cells of the terminal device include at least two SCells of the terminal device or include a PCell and at least one SCell of the terminal device.

[00161] For more detailed descriptions of the determining unit 1410 and the distributing unit 1420 in this implementation, refer directly to the corresponding descriptions in the method shown in Fig. 8 to Fig. 11. The details are not described again.

[00162] Optionally, the communication apparatus 1400 further includes a communication unit 1403 configured to communicate with another device. For example, when the communication apparatus 1400 is a terminal device or is used in a terminal device, the communication unit 1703 is configured to communicate with a network device such as a base station. When the communication apparatus 1400 is a network device such as a base station or is used in a network device, the communication unit 1703 is configured to communicate with the terminal device.

[00163] It should be understood that the division into blocks in the hardware is simply a logical functional division. During the actual implementation, all or some of the blocks may be combined into one physical entity or may be physically separated. In addition, all of the blocks in the hardware may be implemented in the form of software launched by a processing element, or may be implemented in the form of hardware; or some blocks may be implemented in the form of software called by a processing element, and some blocks may be implemented in the form of hardware. For example, each block may be a separately located processing element or may be integrated into a chip of the hardware for implementation. In addition, each block may alternatively be stored in memory as a program that must be called by the processing element of the device to perform the function of the block. In addition, all or some of the blocks may be integrated or may be implemented independently. The processing element may also be called a processor and may be an integrated circuit having the ability to process signals. During implementation, the steps of the above-described methods or the above-described blocks may be implemented using a hardware integrated logic circuit in the processing element or may be implemented in the form of software launched by the processing element.

[00164] For example, a block in any of the above-mentioned devices may be one or more integrated circuits configured to implement the above-mentioned method, such as one or more Application-Specific Integrated Circuits (ASIC), one or more microprocessors (digital signal processors (DSP), one or more field programmable gate arrays (FPGA), or a combination of at least two integrated circuits. As another example, when the blocks in the hardware can be implemented in a form in which the processing element calls a program, the processing element can be a general-purpose processor, such as a central processing unit (CPU) or another processor that can call a program. As another example, the blocks can be integrated and implemented as a system-on-a-chip (SOC).

[00165] The above-mentioned unit (for example, the communication unit) for receiving is an interface circuit of the equipment and is configured to receive a signal from another equipment. For example, when the equipment is implemented as a microcircuit, the receiving unit is an interface circuit belonging to the microcircuit and configured to receive a signal from another microcircuit or equipment. The above-mentioned unit (for example, the sending unit or the communication unit) for sending is an interface circuit of the equipment and is configured to send a signal to another equipment. For example, when the equipment is implemented as a microcircuit, the sending unit is an interface circuit belonging to the microcircuit and configured to send a signal to another microcircuit or equipment.

[00166] FIG. 15 is a schematic diagram of the structure of a network device according to an embodiment of this application. The network device may be a base station and is configured to perform the PDCCH monitoring method provided in the above-mentioned method. As shown in FIG. 15, the network device includes an antenna 1510, a radio frequency apparatus 1520, and a baseband apparatus 1530. The antenna 1510 is connected to the radio frequency apparatus 1520. In the uplink direction, the radio frequency apparatus 1520 receives information sent by a terminal device through the antenna 1510 and sends the information sent by the terminal device to the baseband apparatus 1530 for processing. In the downlink direction, the baseband apparatus 1530 processes information from the terminal device and sends the processed information to the radio frequency apparatus 1520, and the radio frequency apparatus 1520 processes information from the terminal device and then sends the processed information to the terminal device using the antenna 1510.

[00167] The baseband apparatus 1530 may include one or more processing elements 1531, for example, include a main control CPU and another integrated circuit. In addition, the baseband apparatus 1530 may further include a storage element 1532 and an interface circuit 1533. The storage element 1532 is configured to store a program and data. The interface circuit 1533 is configured to exchange information with the radio frequency apparatus 1520, and the interface is, for example, a common public radio interface (CPRI). The above-mentioned apparatus used in the network device may be located in the baseband apparatus 1530. For example, the above-mentioned apparatus used in the network device may be a chip in the baseband apparatus 1530. The chip includes at least one processing element and an interface circuit. The processing element is configured to perform the steps of any PDCCH monitoring method provided in the above-mentioned method. The interface circuit is configured to communicate with other equipment. In the implementation, the units in the network device for implementing the steps in the above-mentioned methods may be implemented in the form of scheduling a program by the processing element. For example, the equipment used for the network device includes a processing element and a storage element. The processing element calls a program stored in the storage element to perform the PDCCH monitoring method provided in the above-mentioned method. The storage element may be a storage element on the same chip as the processing element, i.e. an internal storage element; or may be a storage element that is on a different chip from the processing element, i.e. an external storage element.

[00168] FIG. 16 is a schematic diagram of the structure of a terminal device according to an embodiment of this application. The terminal device is configured to implement the PDCCH monitoring method provided in the above-mentioned method. As shown in FIG. 16, the terminal device includes an antenna 1610, a radio frequency part 1620, and a signal processing part 1630. The antenna 1610 is connected to the radio frequency part 1620. In the downlink direction, the radio frequency part 1620 receives information sent by the network device through the antenna 1610, and sends the information sent by the network device to the signal processing part 1630 for processing. In the uplink direction, the signal processing portion 1630 processes the information of the terminal device and sends the information to the radio frequency portion 1620. The radio frequency portion 1620 processes the information of the terminal device and then sends the processed information to the network device via the antenna 1610.

[00169] The signal processing portion 1630 is configured to process data of each layer of the communication protocol. The signal processing portion 1630 may be a subsystem of a terminal device. The terminal device may further include another subsystem, for example, a central processing subsystem configured to process an operating system and an application layer of the terminal device; and for another example, a peripheral subsystem configured to connect to another device. The signal processing portion 1630 may be a separately located chip. Optionally, the above-mentioned device may be located in the signal processing portion 1630.

[00170] The signal processing section 1630 may include one or more processing elements 1631, for example, include a main control CPU and another integrated circuit. In addition, the signal processing part 1630 may further include a storage element 1632 and an interface circuit 1633. The storage element 1632 is configured to store data and a program. The program used to perform the method performed by the terminal device in the above-mentioned method may or may not be stored in the storage element 1632, for example, stored in a memory outside the signal processing part 1630. When used, the signal processing part 1630 loads the program into a cache for use. The interface circuit 1633 is configured to communicate with hardware. The above-mentioned hardware may be located in the signal processing part 1630. The signal processing part 1630 may be implemented as a chip. The chip includes at least one processing element and an interface circuit. The processing element is configured to perform the steps of any PDCCH monitoring method provided in the above-mentioned method. The interface circuit is configured to communicate with another apparatus. In the implementation, the blocks that implement the steps in the above-mentioned methods may be implemented in the form of a program called by the processing element. For example, the apparatus includes a processing element and a storage element. The processing element calls a program stored in the storage element to perform any PDCCH monitoring method provided in the above-mentioned method. The storage element may be a storage element located on the same chip as the processing element, namely an internal storage element.

[00171] In another implementation, the program used to perform the above-described method performed by the terminal device or the network device may be located in a storage element located on a chip other than the chip of the processing element, namely in an external storage element. In this case, the processing element calls or loads the program from the external storage element to the internal storage element to call and perform any method of monitoring the PDCCH in the above-mentioned embodiments of the method.

[00172] In another implementation, the unit used by the terminal device or the network device to implement the steps of the above-mentioned method may be configured as one or more processing elements. The processing element may be an integrated circuit, such as: one or more ASICs, one or more DSPs, one or more FPGAs, or a combination of these integrated circuits. These integrated circuits may be combined together to form a chip.

[00173] The blocks for implementing the steps of the above-mentioned methods can be combined together and implemented as a system-on-a-chip (SOC). The SOC chip is configured to implement the above-mentioned methods. At least one processing element and a memory element can be integrated into the chip, and the processing element calls a program stored in the memory element to implement the above-mentioned method performed by a terminal device or a network device. Alternatively, at least one integrated circuit can be integrated into the chip to implement the above-mentioned method performed by a terminal device or a network device. Alternatively, referring to the previous implementations, the functions of some blocks can be implemented as a program launched by the processing element, and the functions of some blocks can be implemented as an integrated circuit.

[00174] In another implementation, an embodiment of this application provides a communication apparatus. The communication apparatus may include at least one processing element and an interface circuit. The at least one processing element is configured to perform any method of monitoring a PDCCH provided in the above-mentioned method. The processing element may perform part or all of the steps performed by the terminal device or the network device, firstly, if specifically, by calling a program stored in a storage element; or may perform part or all of the steps performed by the terminal device or the network device, in a second way, if specifically, using a hardware integrated logic circuit in the processing element in combination with instructions; or, of course, may perform, by combining the first method and the second method, part or all of the steps performed by the terminal device or the network device. It is understood that the interface circuit may be a transceiver or an input/output interface. Optionally, the communication apparatus may further include a memory configured to store instructions executed by the above-mentioned processing element, or to store input data required by the processing element to execute the instructions, or to store data generated after the processing element executes the instructions.

[00175] As described above, the processing element may be a general-purpose processor, such as a CPU, or may be one or more integrated circuits configured to implement the above-mentioned methods, such as one or more ASICs, one or more DSP microprocessors, one or more FPGAs, or a combination of at least two integrated circuits. The storage element may be a single memory device (memory) or may be a general term for a plurality of storage elements.

[00176] It may be clear to a person skilled in the art that all or some of the steps of the method may be implemented by a program that gives instructions to the corresponding hardware. The program may be stored on a machine-readable storage medium. When the program is started, the steps of the above-mentioned method are performed. The above-mentioned storage medium includes any medium that can store program code, such as ROM, RAM, magnetic disk or optical disk.

[00177] The resource in the embodiments of this application may also be referred to as a transmission resource, including one or more time domain resources, a frequency domain resource, and a code channel resource. The resource may be used to carry data or signaling in an uplink communication process or in a downlink communication process.

[00178] It should be understood that the term "and/or" in this description describes only the association relationship between associated objects and represents that three relationships may exist. For example, A and/or B may represent the following three cases: only A exists, both A and B exist, and only B exists.

[00179] It should be understood that in the terms of the present invention, "B corresponding to A" means that B is related to A, and B can be determined based on A. However, it should also be understood that determining B based on A does not mean that B is determined based on A alone. Alternatively, B can be determined based on A and/or other information.

[00180] “Plurality” in embodiments of this application refers to two or more than two.

[00181] Descriptions such as "first" and "second" in the embodiments of this application are used only to indicate and distinguish between the objects described, do not indicate a sequence, do not indicate a specific limitation on the number of objects described in this application, and cannot constitute any limitation on this application.

[00182] In embodiments of this application, unless otherwise specified, "transmit" (transmission) refers to bidirectional transmission and includes an action of sending and/or an action of receiving. In particular, "transmit" in this application includes sending data, receiving data, or sending and receiving data. In other words, data transmission includes uplink data transmission and/or downlink data transmission. Data may include information and/or a signal. Uplink data transmission is uplink information transmission and/or uplink signal transmission, and downlink data transmission is downlink information transmission and/or downlink signal transmission.

[00183] It can be understood that in the background of this application, the terminal device and/or the network device may perform some or all of the steps in the background of this application. These steps or operations are merely examples. According to the decision of this application, other operations or variations of various operations may be additionally performed. In addition, the steps may be performed in a sequence different from the sequence presented in this application, and not all operations in this application may necessarily be performed.

Claims (41)

1. A method for monitoring a physical downlink control channel, comprising: determining that a first monitoring opportunity of the terminal device is used to monitor physical downlink control channels of a certain set of cells of the terminal device, wherein the set of cells comprises at least two cells of the terminal device, and each cell in the set of cells has the same interval pattern and the same subcarrier spacing; defining N non-overlapping time units of a set of cells in a single slot, wherein the initial location of each of the N time units is based on a cell interval in the set of cells, and N is a positive integer; and allocating a first monitoring opportunity to a set of cells based on N time units for separately monitoring the physical downlink control channel of each cell in the set of cells. 2. The method according to claim 1, wherein the distribution of the first monitoring opportunity in the set of cells based on N time units comprises: distribution of the first allocation opportunity in the interval of each cell in each of the N time units. 3. The method according to item 1 or 2, wherein: the index of the starting symbol of the first time unit in N time units is the smallest index in the indices of the starting symbols of all intervals in the set of cells; and the index of the starting symbol of the second time unit in N time units is the smallest index in the indices of the starting symbols of intervals that are in all intervals in the set of cells and do not overlap the first time unit. 4. The method according to any one of claims 1-3, wherein at least two cells of the terminal device comprise at least two secondary cells SCells of the terminal device, or comprise a primary cell PCell of the terminal device and at least one SCell of the terminal device. 5. The method according to any one of paragraphs 1-4, wherein the distribution of the first monitoring opportunity in the set of cells based on N time units comprises: when the symbols occupied by the first interval of the first cell partially or completely overlap with the first time unit, allocating a portion or all of the first monitoring opportunity to the first cell based on the number of all symbols occupied by the interval of the first cell, wherein the first cell is a cell in a set of cells, and the first time unit is one of the N time units. 6. The method according to any one of paragraphs 1-5, wherein the distribution of the first monitoring opportunity in the set of cells based on N time units comprises: when the symbols occupied by the interval of the second cell partially or completely overlap with the second time unit, distributing a portion or all of the first monitoring opportunity to the second cell based on a proportion of the number of symbols in the overlapping portion to the number of symbols occupied by the interval of the second cell, wherein the second cell is a cell in a set of cells, and the second time unit is one of the N time units. 7. The method according to any one of paragraphs 1-6, wherein each interval of each cell in the set of cells is located in one of N time units. 8. The method according to any one of paragraphs 1-7, wherein the number of consecutive symbols contained in one of the N time units is the same with a minimum spacing of symbols between the initial symbols of two adjacent intervals, specified by the interval template. 9. The method of claim 8, wherein the interval template is represented as (X,Y), X represents the minimum spacing of symbols between the initial symbols of two intervals, and Y represents the maximum number of consecutive symbols contained in the interval, wherein the number of consecutive symbols contained in a unit of time is equal to X symbols. 10. The method according to paragraphs. 1-9, wherein the first monitoring capability of the terminal device is determined based on the maximum number of cells supported by the terminal device for monitoring the physical downlink control channel, and the monitoring capability corresponding to the interval template corresponding to the first set of cells. 11. The method according to any one of claims 1-10, wherein the first monitoring opportunity comprises a maximum number of times the terminal device monitors the candidate physical downlink control channel and/or a maximum number of non-overlapping control channel elements used to monitor the candidate physical downlink control channel. 12. The method according to any one of claims 1-11, wherein when the set of cells comprises a primary cell PCell of the terminal device and a secondary cell SCell of the terminal device, the monitoring capability for the PCell is preferably allocated. 13. Communication equipment containing: a determining unit configured to: determine that a first monitoring opportunity of the terminal device is used to monitor physical downlink control channels of a set of cells of the terminal device, wherein the set of cells comprises at least two cells of the terminal device, and each cell in the set of cells has the same interval pattern and the same subcarrier spacing; and determine N non-overlapping time units of the set of cells in one slot, wherein the starting location of each of the N time units is based on an interval of a cell in the set of cells, and N is a positive integer; and a distribution unit configured to distribute a first monitoring opportunity to the set of cells based on N time units, for separately monitoring a physical downlink control channel of each cell in the set of cells. 14. The apparatus of claim 13, wherein the distribution unit is configured to distribute the first monitoring opportunity in the interval of each cell in each of the N time units. 15. The apparatus according to item 13 or 14, wherein: the index of the starting symbol of the first time unit in N time units is the smallest index in the indices of the starting symbols of all intervals in the set of cells; and the index of the starting symbol of the second time unit in N time units is the smallest index in the indices of the starting symbols of intervals that are in all intervals in the set of cells and do not overlap the first time unit. 16. The apparatus according to any one of claims 13-15, wherein at least two cells of the terminal device comprise at least two secondary cells SCells of the terminal device, or comprise a primary cell PCell of the terminal device and at least one SCell of the terminal device. 17. The apparatus of any one of paragraphs 13-16, wherein the distribution unit is specifically configured to: when the symbols occupied by the first interval of the first cell partially or completely overlap with the first time unit, allocate a portion or all of the first monitoring opportunity to the first cell based on the number of all symbols occupied by the interval of the first cell, wherein the first cell is a cell in a set of cells, and the first time unit is one of the N time units. 18. The apparatus of any one of paragraphs 13-17, wherein the distribution unit is specifically configured to: when the symbols occupied by the interval of the second cell partially or completely overlap with the second time unit, distributing a portion or all of the first monitoring opportunity to the second cell based on a proportion of the number of symbols in the overlapping portion to the number of symbols occupied by the interval of the second cell, wherein the second cell is a cell in a set of cells, and the second time unit is one of the N time units. 19. The apparatus according to any one of paragraphs 13-18, wherein each interval of each cell in the set of cells is located in one of N time units. 20. The apparatus according to any one of paragraphs 13-19, wherein the number of consecutive symbols contained in one of the N time units is the same with a minimum spacing of symbols between the initial symbols of two adjacent intervals specified by the interval template. 21. The apparatus of claim 20, wherein the interval pattern is represented as (X,Y), X representing the minimum symbol spacing between the initial symbols of two intervals, and Y representing the maximum number of consecutive symbols contained in an interval, wherein the number of consecutive symbols contained in a unit of time is equal to X symbols. 22. The apparatus of paragraphs 13-21, wherein the first monitoring capability of the terminal device is determined based on the maximum number of cells supported by the terminal device for monitoring the physical downlink control channel and the monitoring capability corresponding to the interval template corresponding to the first set of cells. 23. The apparatus according to any one of paragraphs 13-22, wherein the first monitoring opportunity comprises a maximum number of times the terminal device monitors the candidate physical downlink control channel and/or a maximum number of non-overlapping control channel elements used to monitor the candidate physical downlink control channel. 24. The apparatus according to any one of paragraphs 13-23, wherein when the set of cells comprises a primary cell PCell of the terminal device and a secondary cell SCell of the terminal device, the monitoring capability for the PCell is preferably distributed. 25. Communication equipment comprising at least one processing element and an interface circuit, wherein at least one processing element is configured to execute a computer program stored in a memory, such that the communication equipment performs the method according to any one of claims 1-12. 26. A machine-readable data carrier, wherein a computer program is stored on the machine-readable data carrier, and the computer program enables a computer to perform the method according to any of paragraphs 1-12.

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