JP6865378B2 - Base station equipment and communication method - Google Patents

Description

The present disclosure relates to a base station apparatus and a communication method in an FD-MIMO (full dimension multiple-input multiple-output) communication system in LTE (Long Term Evolution).

Beam formation, a type of multiplex antenna technology, has already been adopted in early Long Term Evolution (LTE) standard releases to improve coverage capabilities. For this technology, people have focused mainly on the azimuth region. For example, how to form a horizontal beam using some kind of weight vector has been studied. In the elevation region, fixed downtilts rather than some kind of dynamic beam are supported in current LTE systems.

As the requirements for elevation region beam formation increase, 3D beam formation will become increasingly important, especially in urban areas where users are located on different floors of the building. Using traditional horizontal beam formation techniques has not been very useful to these users, so beam formation must be considered in both the elevation and horizontal regions, which is actually a 3D beam. It is a formation.

FIG. 1 shows an example of normal 3D beam formation. As shown in FIG. 1, a 3D beam transmitted from an eNB (base station) 101 provides a service to a user on a specific floor of a building 102. The beam can also dynamically serve users on different floors. Therefore, 3D beam forming can further improve system performance using a vertical antenna unit (or vertical beam forming) and potentially reduce interference with other cells. An active antenna system (AAS) is the basis for achieving 3D beam formation.

FIG. 2 shows an outline of the AAS (Active antenna system) radio architecture in 3GPP TR37.840. As shown in FIG. 2, the transceiver unit array (TUA) 201 assumes a one-to-one mapping between transceiver units # 1, # 2, ... # K and the antenna port. The Radio Distribution Network (RDN) 202 can provide a mapping between the TUA 201 and the antenna array 203. By using the AAS system, the network can dynamically adjust all elevation (or downward tilt) and azimuth angles of the beam with the associated beamwidth.

As 3GPP TR37.840 shows, wide area AAS (macro AAS), medium range AAS (micro AAS), and local area AAS, depending on the level of minimum coupling loss, the position of the eNB (base station) antenna, etc. There can be different AAS installation scenarios, such as coverage AAS (pico AAS). The range of each AAS scenario can benefit from 3D beam formation.

In 3GPP Release 12, two potential considerations for 3D beam formation will be discussed. That is, one is elevation beam formation and the other is FD-MIMO. The former assumes up to 8 antenna ports and the latter can support {16,32,64} or even larger antenna ports. An antenna port is a type of logical signal that can be transmitted by several antenna units (physical antennas).

FIG. 3 shows FD-MIMO with an 8x8 antenna array structure. As shown in FIG. 3, FD-MIMOs that potentially support 64 antenna units may require 64 CSI-RS ports to estimate channels in Full Dimension. It has an 8 × 8 antenna array structure, and the distance between the antennas may be 0.5λ.

FIG. 4 schematically shows the CSI-RS region for each PRB (physical resource block) in LTE release 11. As shown in FIG. 4, the area indicated by the diagonal line “\” is the CSI-RS port on the PRB for transmitting the CSI-RS signal from the base station to the user equipment. If it is true that 64 CSI-RS ports are needed for FD-MIMO, the problem is that in the current release 11 of LTE, only 40RE (resource element) is used as the CSI-RS port per PRB. Is to be done. Therefore, the question is how to assign the CSI-RS port to the 64 antenna unit.

The present disclosure is made in consideration of the above-mentioned aspects.

According to one aspect of the present disclosure, it is a communication method that maps CSI-RS ports to antenna units arranged in an antenna array system, in which one group of antenna units is selected and the first CSI. Select the step of mapping the CSI-RS port in the -RS transmission period or the first frequency resource area and another group of antenna units, and select the CSI in the second CSI-RS transmission period or the second frequency resource area. -Provides a method that includes a step to map the RS port. In this aspect, multiple groups of antenna units may be selected to map CSI-RS ports to different CSI-RS transmission periods.

According to the aforementioned aspects, one part of the CSI-RS port that maps to the antenna unit reflects the first channel vector and another part of the CSI-RS port that maps to the antenna unit is the first. Reflects a second channel vector that is orthogonal or quasi-orthogonal to the channel vector of.

According to the aforementioned aspects, that portion of the CSI-RS port reflecting the first channel vector and / or the other portion of the CSI-RS port reflecting the second channel vector is in the frequency domain or time domain. Is further distributed separately.

According to another aspect of the present disclosure, a communication method of mapping a CSI-RS port to antenna units arranged in an antenna array system, wherein one group of antenna units is selected and the first. The step of mapping the CSI-RS port in the CSI-RS transmission period or the first frequency resource domain and another group of antenna units are selected and in the second CSI-RS transmission period or the second frequency resource domain. A method is provided in which the antenna units within each group are separately distributed in the frequency domain or time domain, including the step of mapping the CSI-RS ports.

According to a further aspect of the present disclosure, it is a communication method that maps CSI-RS ports to antenna units arranged in an antenna array system, in which one group of antenna units is selected and the CSI of the resource block. A method is provided in which resource blocks are sparsely selected on a flatter specific region channel for mapping antenna units and CSI-RS ports, including the step of mapping the -RS ports.

According to a further aspect of the present disclosure, a base station for mapping CSI-RS ports to antenna units arranged within an antenna array system, the first group of antenna units being selected. Map the CSI-RS port in the CSI-RS transmission period or the first frequency resource area, select another group of antenna units, and select the CSI in the second CSI-RS transmission period or the second frequency resource area. -A base station is provided with a mapping unit configured to map the RS port. In this aspect, the mapping unit can select multiple groups of antenna units and map CSI-RS ports to different CSI-RS transmission periods.

According to the aforementioned aspects, one part of the CSI-RS port that maps to the antenna unit reflects the first channel vector, and another part of the CSI-RS port that maps to the antenna unit is the first. It reflects a second channel vector that is orthogonal or quasi-orthogonal to the channel vector.

According to the aforementioned aspects, that portion of the CSI-RS port reflecting the first channel vector and / or the other portion of the CSI-RS port reflecting the second channel vector is in the frequency domain or time domain. Is further distributed separately.

According to a further aspect of the present disclosure, a base station that maps a CSI-RS port to antenna units arranged within an antenna array system, selecting a group of antenna units and a first CSI. Map the CSI-RS port in the −RS transmission period or the first frequency resource region, select another group of antenna units, and select the CSI-RS in the second CSI-RS transmission period or the second frequency resource region. A base station is provided that includes mapping units configured to map ports, with antenna units within each group distributed separately in the frequency or time domain.

According to a further aspect of the present disclosure, a base station that maps CSI-RS ports to antenna units arranged within an antenna array system, selecting one group of antenna units and CSI of resource blocks. A base with mapping units configured to map -RS ports, where resource blocks are sparsely selected in certain flatter region channels for mapping antenna units and CSI-RS ports. The station is provided.

According to a further aspect of the present disclosure, one group of antenna units in an antenna array maps a CSI-RS port in a first CSI-RS transmission period or a first frequency resource region and its antenna array. A receiving unit configured to receive a message from a base station indicating that another group of antenna units within it maps a CSI-RS port in a second CSI-RS transmission period or a second frequency resource region. A user device is provided. In this aspect, the message further indicates that multiple groups of antenna units map CSI-RS ports to different CSI-RS transmission periods.

According to the aforementioned aspect, one part of the CSI-RS port that maps to the antenna unit reflects the first channel vector, and another part of the CSI-RS port that maps to the antenna unit is the first. It reflects a second channel vector that is orthogonal or quasi-orthogonal to the channel vector.

According to the aforementioned aspects, that portion of the CSI-RS port reflecting the first channel vector and / or the other portion of the CSI-RS port reflecting the second channel vector is in the frequency domain or time domain. Is further distributed separately.

According to a further aspect of the present disclosure, one group of antenna units maps CSI-RS ports in the first CSI-RS transmission period or first frequency resource domain, and another group of antenna units is the first. An antenna unit within each group comprises a receiving unit configured to receive a message from a base station indicating that it maps a CSI-RS port in two CSI-RS transmission periods or a second frequency resource domain. User equipment is provided that is separately distributed in the frequency domain or time domain.

According to a further aspect of the present disclosure, the resource block comprises a receiving unit configured to receive a message from a base station indicating that one group of antenna units maps the CSI-RS port of that resource block. User equipment is provided that is sparsely selected in a specific region channel that is flatter for mapping antenna units and CSI-RS ports.

The base station apparatus and communication method of the present disclosure has the advantage that each antenna unit will have a relatively fair opportunity to perform CSI-RS port transmission and will have good channel estimation performance. Can be realized.

A detailed description of the embodiments of the present disclosure, along with accompanying drawings such as the following, will clarify and facilitate understanding of these and / or other aspects and advantages of the present disclosure.

The figure which shows an example of the conventional 3D beam formation Diagram showing a typical AAS radio architecture in 3GPP TR37.840 The figure which shows FD-MIMO which has an 8 × 8 antenna array structure. The figure which shows the CSI-RS area for each PRB in the release 11 of LTE schematicly. Diagram showing two CSI-RS resources reflecting an orthogonal channel vector Diagram showing a fixed mapping scenario for the transmitting antenna unit and CSI-RS port A block diagram schematically showing a base station (eNB) according to an embodiment of the present disclosure. The figure which shows the antenna unit-CSI-RS port mapping variation in the time domain by 1st Example of this disclosure. The figure which shows the antenna unit-CSI-RS port mapping variation in the frequency domain by 1st Example of this disclosure. FIG. 5 showing variable antenna unit-CSI-RS port mapping according to a second embodiment of the present disclosure. A diagram showing different allocation patterns of CSI-RS resources reflecting different orthogonal channel vectors according to a third embodiment of the present disclosure. A block diagram schematically showing a user device (UE) according to an embodiment of the present disclosure. Flow diagram of a method of mapping a CSI-RS port to an antenna unit according to the first embodiment of the present disclosure. Flow diagram of the method of mapping the CSI-RS port to the antenna unit according to the second embodiment of the present disclosure. Flow diagram of the method of mapping the CSI-RS port to the antenna unit according to the third embodiment of the present disclosure.

In the following detailed description, reference is made to the accompanying drawings that form part of this disclosure. In drawings, similar symbols usually refer to similar components, unless otherwise indicated by context. It is readily understood that aspects of the present disclosure may be sequenced, substituted, linked, and designed in a wide variety of different configurations, all of which are expressly contemplated and form part of the present disclosure. Yeah.

Although the main focus of this specification is on macro AAS scenarios, any of the other scenarios mentioned above can also be feasible examples. Although FD-MIMO with 64 antenna units is given herein as an example, the present disclosure also includes FD-MIMO smaller or larger than 64 antenna units, or elevation beam formation that supports only 8 antenna ports. It can also be used in other cases.

FIG. 5 shows two CSI-RS resources that reflect the orthogonal channel vector. To solve the problems described in the background art, one direct method is for the eNB to send two orthogonal CSI-RS resource groups (each group has 8 CSI-RS ports) for emergency CSI- It is to alleviate the need for RS resources. For example, two orthogonal CSI-RS resource groups are transmitted, one reflecting the horizontal region channel and the other reflecting the vertical region channel. The user can reconstruct the entire 8x8 antenna array channel using two orthogonal CSI-RS resource groups by using the correlation characteristics of the full-dimensional antenna array. This can suffer some performance loss, but greatly reduces the need for CSI-RS ports.

Although the above-mentioned direct method may be feasible, it has some problems that can affect the 3D beam forming performance. One issue (problem-I) is the unstable channel estimation performance due to the fixed mapping of the transmitting antenna unit to the CSI-RS port.

FIG. 6 shows a fixed mapping scenario for the transmitting antenna unit and the CSI-RS port. As shown in FIG. 6, when the antenna units in rows 2 and 3 are used for mapping to CSI-RS ports for transmission of CSI-RS signals, they are indicated by arrows 1 and are shown in rows 2 and 3 Some areas, such as rows 7 and columns 7 of the antenna unit away from, may have undesired channel estimation performance. Alternatively, if row 7 and column 6 of the antenna unit are used to map to the CSI-RS port for transmission of the CSI-RS signal, row 2 and column 2 of the antenna unit indicated by arrow 2. Some areas, such as, may have some undesired channel estimation performance. Even when considering the relatively intermediate regions of the antenna unit to map the CSI-RS ports, the edge regions may also have undesired channel estimation performance. However, instead, the region close to the antenna unit for mapping the CSI-RS port will have relatively good channel estimation performance.

With respect to Task-I described above, the present disclosure proposes a solution for variable mapping of antenna units to CSI-RS ports in order to average channel estimation instability in a direct way. This variable mapping eliminates the channel estimation performance degradation that can be caused by conventional methods by averaging the channel estimation differences between different antenna units (in the time, frequency or mixed region). A common example of a variable mapping pattern is to periodically shift the mapping of antenna units and CSI-RS ports. With respect to mapping patterns, in addition to the usual orthogonal crossing patterns, there are also other partial crossing or distribution patterns that can be configured by physical signaling, MAC or RRC (Radio Resource Control) signaling based on certain rules. Can be used. The crosspoint index of the intersection pattern can also be used as a simple way to indicate the mapping pattern.

Another problem (Problem-II) is the large overhead of CSI-RS resources. The above scenario also still requires a 16 CSI-RS port. Downlink efficiency can be significantly affected when CoMP or other reference signals are considered, and therefore some method for further mitigating the CSI-RS overhead needs to be considered.

With respect to Task-II described above, the present disclosure provides different subdivisions for each orthogonal CSI-RS resource in order to further reduce the downlink overhead by considering the possible different properties of the horizontal and vertical region channels. It is proposed to assign the pattern to have. For example, if the region channel in one direction (eg, the vertical region channel) is flatter, a relatively sparse CSI-RS resource that reflects the vertical region channel can be sent in some way.

The present disclosure, along with the drawings, will be described below.

(First Example)
A first embodiment of the present disclosure is a variable mapping of an antenna unit and a CSI-RS port.

FIG. 7 is a block diagram schematically showing a base station (eNB) 700 according to an embodiment of the present disclosure. In this embodiment, the eNB 700 has the function of mapping the CSI-RS port to the antenna units arranged in the antenna array system. The eNB 700 selects one group of antenna units, maps the CSI-RS ports in the first CSI-RS transmission period or the first frequency resource region, selects another group of antenna units, and a second. Includes a mapping unit 701 configured to map CSI-RS ports during the CSI-RS transmission period or second frequency resource region of.

8A and 8B show variable antenna unit-CSI-RS port mapping according to the first embodiment of the present disclosure. Specifically, FIG. 8A shows the antenna unit-CSI-RS port mapping variation in the time domain according to the first embodiment, and FIG. 8B shows the antenna unit in the frequency domain according to the first embodiment. -CSI-RS port mapping variation is shown. In this embodiment, as shown in FIGS. 3 and 4, a plurality of antenna units are arranged in an 8 × 8 antenna array, and the number of CSI-RS ports is less than 40.

Specifically, as shown in FIG. 8A, the mapping unit 701 selects a group of antenna units and maps a particular CSI-RS port during the first CSI-RS transmission period. For example, in TTI (Transmission Time Interval) #N, pattern "a" is used and the row 2 and column 3 antenna units are selected to map the CSI-RS ports. Mapping unit 701 selects another group of antenna units and maps a particular CSI-RS port during the second CSI-RS transmission period. For example, in TTI # (N + P), pattern "b" is used and the row 4 and column 4 antenna units are selected to map the CSI-RS ports. Here, "P" is the period of CSI-RS transmission, for example, 5 ms.

Alternatively, as shown in FIG. 8B, the mapping unit 701 can select a group of antenna units to map a particular CSI-RS port in the first frequency resource region. For example, in PRB (Physical Resource Block) #M, pattern "a" is used and the antenna units in rows 2 and columns 3 are selected to map the CSI-RS ports. The mapping unit 701 can select another group of antenna units and map the CSI-RS port in the second frequency resource area. For example, in PRB # Q, pattern "b" is used and the antenna units in rows 4 and columns 4 are selected to map the CSI-RS ports.

In this embodiment, the mapping unit 701 can select multiple groups of antenna units and map CSI-RS ports in different CSI-RS transmission periods or different frequency resource regions. For example, an additional pattern "c" is used in TTI # (N + 2P) shown in FIG. 8A or PRB # R shown in FIG. 8B for row 6 and column 5 of the antenna unit to map the CSI-RS port. Be selected. Here, PRBs # M, # Q, and # R are resource blocks distributed in the frequency domain of the communication system.

In this embodiment, one part of the CSI-RS port that maps to the antenna unit reflects the first channel vector, and another part of the CSI-RS port that maps to the antenna unit is the first channel. It reflects a second channel vector that is orthogonal or quasi-orthogonal to the vector. For example, as shown in FIG. 8, the CSI-RS port that maps to the antenna units in rows 2, 4, and 6 reflects the horizontal channel vector and the antenna units in columns 3, 4, and 5. The CSI-RS port that maps to reflects the vertical channel vector.

In this embodiment, the eNB 700 provides a transmit unit 702 configured to transmit a CSI-RS signal by periodically shifting a group of antenna units selected for mapping to a CSI-RS port. Further prepared. For example, in the next period, the pattern a-> b-> c will be applied again. This is a simple example of a periodic shift in the mapping pattern of the antenna unit and the CSI-RS port.

Pattern variation can not only be shifted cyclically, but can also be based on some rule, such as a randomization formula. That is, the transmitting unit 702 can transmit the CSI-RS signal by randomly shifting a group of antenna units selected to map the CSI-RS port. The randomized seed can depend on the subframe index. According to another embodiment, the pattern variation can be based on a predefined set of candidates on both the eNB side and the UE side.

CSI-RS port and antenna unit mapping and associated variation mode indications can be configured quasi-statically by RRC signaling with respect to UE-specific or cell-specific methods. In this embodiment, the transmission unit 702 can transmit a message (information) indicating the mapping of the CSI-RS port and the antenna unit configured by RRC signaling or DCI signaling to the UE. The following is an example of such an instruction by RRC signaling:
CSI-RS_antenna-unit_mapping-r12 {
Mode: 0: full CSI-RS is transmitted 1: two orthogonal CSI-RS resources are transmitted
If (1),
{
CSI-RS ports number (for example 16);
Mapping pattern variation mode: 0: randomly changed 1: cyclic shift; 2: dynamic indication in L1 among four candidates 3: never changed;
If (0), random seed is based on subframe index;
If (1), cyclic excluded pattern;
If (2), four candidates set;
If (3), special pattern;
}
}

The aforementioned message may be an extension of CSI-RS-ConfigNZP-r11 in the 3GPP36.331 specification. In this embodiment, in an L1-based manner, the transmission of instructions is in either a common search space or a UE-specific search space, with some fields in the DCI (downlink control information) (eg, CIF, etc.). RA) is reused.

If two orthogonal CSI-RS resources are envisioned, there may be two options for how to indicate the specific location of the antenna unit that maps the CSI-RS ports in the 2D antenna array. One option is to use the coordinates directly. That is, the mapping instructions for the CSI-RS port and antenna unit can be represented by coordinates. For example, in this embodiment, the coordinates {4,4} are for the antenna units in rows 4 and columns 4 in the 2D antenna array to map the CSI-RS ports as shown in FIGS. 8A and 8B. Indicates that it will be used for. Similarly, coordinates (2,3) indicate that the row 2 and column 3 antenna units in the 2D antenna array are used to map the CSI-RS port, and coordinates (6,). 5) indicates that the row 6 and column 5 antenna units in the 2D antenna array are used to map the CSI-RS ports.

Another option is to use a crosspoint index. That is, according to another embodiment of the present disclosure, the CSI-RS port and antenna unit mapping instructions can be represented by a crosspoint index. For example, the crosspoint index "11" indicates that the row 2 and column 3 antenna units in the 2D antenna array are used to map the CSI-RS ports, as shown in FIGS. 8A and 8B. Used to indicate. Similarly, the crosspoint index "28" indicates that the row 4 and column 4 antenna units in the 2D antenna array are used to map the CSI-RS ports, and the crosspoint index "45". Indicates that the row 6 and column 5 antenna units in the 2D antenna array are used to map the CSI-RS ports.

Considering that the absolute value of 11 or 28 requires 4 or 5 bits to further reduce the pointing overhead at a particular location of the antenna unit, for example in the L1-based method, a smaller number of bits are also said. It is possible for such instructions. For example, four patterns (pattern variation sets) are indicated by RRC signaling, where two bits instead of four or five bits in L1 signaling indicate a pattern of mapping of CSI-RS ports and antenna units. Used for.

The eNB 700 according to the present disclosure further executes related programs to process various data, and executes various processing and control by the CPU (central processing unit) 710 and the CPU 710 for controlling the operation of each unit in the eNB 700. ROM (read-only memory) 713 for storing various programs required for this, and RAM (random access memory) for storing intermediate data temporarily created by the processing and control procedures by the CPU 710. A memory) 715 and / or a storage device 717 for storing various programs, data, etc. may be included. The above-mentioned mapping unit 701, transmission unit 702, CPU 710, ROM 713, RAM 715 and / or storage device 717 and the like can be interconnected via data and / or command bus 720 and transfer signals one after another. can do.

Each of the above units does not limit the scope of this disclosure. According to one embodiment of the present disclosure, the functionality of mapping unit 701 and transmission unit 702 can also be implemented by one unit, and any or a combination of mapping unit 701 and transmission unit 702. Functions may also be implemented by functional software in combination with CPU 710, ROM 713, RAM 715 and / or storage device 717 and the like.

In the first embodiment of the present disclosure, each antenna unit will have a relatively fair opportunity to transmit the CSI-RS signal, or will have a fairly good channel estimation performance.

(Second Example)
A second embodiment is that the applied CSI-RS port-antenna unit mapping pattern can be more distributed rather than always in one column and one row.

FIG. 9 shows variable antenna unit-CSI-RS port mapping according to a second embodiment of the present disclosure.

According to a second embodiment of the present disclosure, the mapping unit 701 (shown in FIG. 7) selects one group of antenna units and in the first CSI-RS transmission period or the first frequency resource domain. CSI-RS ports can be mapped, another group of antenna units can be selected, and CSI-RS ports can be mapped in the second CSI-RS transmission period or the second frequency resource domain, within each group. Antenna units can be more separately distributed in the frequency domain or time domain.

Specifically, in the second embodiment of the present disclosure, one portion of the CSI-RS port that maps to the antenna unit can reflect the first channel vector and the CSI- that maps to the antenna unit. Another part of the RS port can reflect a second channel vector that is orthogonal or quasi-orthogonal to the first channel vector. In this embodiment, the first channel vector may be, for example, a vertical channel vector, and the second channel vector may be, for example, a horizontal channel vector. Further, according to a second embodiment of the present disclosure, that portion of the CSI-RS port that reflects the first channel vector (eg, vertical channel vector) is further distributed separately in the frequency domain or time domain. And / or the other part of the CSI-RS port that reflects the second channel vector (eg, the horizontal channel vector) is further distributed separately in the frequency domain or time domain.

For example, as shown in FIG. 9, the CSI-RS port 901 reflecting the vertical channel vector is divided into two parts, and the CSI-RS port 902 reflecting the horizontal channel vector is divided into two parts. .. Here, the two parts may be three or more parts, and other methods may be applied which do not limit the scope of the present disclosure or disperse the CSI-RS ports more separately. This scheme can potentially help disperse the antenna units more and eliminate channel estimation differences between the antenna units.

Similar to the first embodiment, the mapping unit 701 can also select multiple groups of antenna units to map CSI-RS ports in different CSI-RS transmission periods or different frequency resource regions. The transmit unit 702 transmits a CSI-RS signal by periodically shifting a group of antenna units selected for mapping to a CSI-RS port, or to map a CSI-RS port. The CSI-RS signal can be transmitted by randomly shifting the group of selected antenna units. The transmission unit 702 can transmit to the UE a message or information indicating the mapping of the CSI-RS port and antenna unit configured by RRC signaling or DCI signaling. Messages or information regarding CSI-RS port and antenna unit mapping instructions can reuse some fields of DCI signaling in either the common search space or the UE-specific search space.

The indication of a specific location of the antenna unit for mapping the CSI-RS port can also be represented by coordinates. However, in the second embodiment of the present disclosure, the instructions are given because more bits are needed to indicate which antenna unit is selected to map the CSI-RS port. It's more complicated. As shown in FIG. 9, for example, the coordinates {6,0,2,1; 3,0,6,1} can be used for such an indication, "6,0,2,1". Indicates the first half (0) of row 6 and the second half (1) of row 2, and "3,0,6,1" indicates the first half (0) of column 3 and the second half (1) of column 6.

In the aforementioned second embodiment of the present disclosure, each antenna unit will have a relatively fair opportunity to transmit the CSI-RS signal or will have reasonably good channel estimation performance.

(Third Example)
A third embodiment of the present disclosure uses a differentiated allocation pattern for two orthogonal CSI-RS resources.

FIG. 10 shows different allocation patterns of CSI-RS resources that reflect different orthogonal channel vectors according to a third embodiment of the present disclosure.

In FIG. 10, multiple physical resource blocks (PRBs) arranged in the frequency domain are shown, and two orthogonal CSI-RS resources that reflect the horizontal and vertical channel vectors are also shown. As shown in FIG. 10 (a), the group of CSI-RS resources 1 to 7 reflecting the horizontal channel vector indicated by the diagonal line “/” and the CSI reflecting the vertical channel vector indicated by the diagonal line “\”. -Another group of RS resources 1-7 is used uniformly.

However, in some scenarios, the vertical region channel may be flatter than the horizontal region channel. In this regard, according to a third embodiment of the present disclosure, the mapping unit 701 of the eNB 700 (shown in FIG. 7) selects one group of antenna units and provides some CSI-RS ports in the resource block. It can be mapped and its resource blocks are sparsely selected in certain flatter region channels for mapping antenna units and CSI-RS ports. Specifically, as shown in FIG. 10B, high density CSI-SR resource blocks 1-7 are used for horizontal region channels and relatively sparse CSI-RS resource blocks 1, 3, 5 , 7 are used for the vertical region channel. That is, if the vertical domain channel is flatter, the mapping unit 701 can select resource blocks at intervals in the frequency domain of the vertical domain channel.

However, on the other hand, if the horizontal region channel is flatter, a relatively sparse distribution of resource blocks reflecting the horizontal region channel can be used, as shown in FIG. 10 (c).

In the third embodiment of the present disclosure, the selection of each resource block for mapping the antenna unit and the CSI-RS port is notified from the eNB 700 to the UE via RRC signaling, for example with the following message:
{
1st / horizontalCSI-RSresourcedistributionbitmap;
2 ^nd / verticalCSI-RSresourcedistributionbitmap;
}

The third embodiment of the present disclosure can be used in combination with or based on the first or second embodiment described above.

In the aforementioned third embodiment of the present disclosure, each antenna unit will have a relatively fair opportunity for transmission of the CSI-RS signal or a fairly good channel estimation performance.

FIG. 11 is a block diagram showing a terminal (UE) according to an embodiment of the present disclosure. As shown in FIG. 11, the UE 1100 includes a receiving unit 1101 configured to receive a message from the eNB 700, the message being transmitted by a group of antenna units in the antenna array as the first CSI-RS. Mapping a CSI-RS port in a period or first frequency resource area, and another group of antenna units in its antenna array can CSI in a second CSI-RS transmission period or second frequency resource area. -Indicates that the RS port is mapped.

In this embodiment, one part of the CSI-RS port that maps to the antenna unit reflects the first channel vector, and another part of the CSI-RS port that maps to the antenna unit is the first channel. It reflects a second channel vector that is orthogonal or quasi-orthogonal to the vector. Specifically, in this embodiment, the CSI-RS port that maps to the antenna unit in rows reflects the horizontal channel vector, and the CSI-RS port that maps to the antenna unit in columns reflects the vertical channel vector. To do.

In this embodiment, the portion of the CSI-RS port that reflects the first channel vector is further distributed separately in the frequency domain or time domain, and / or the CSI- that reflects the second channel vector. The other part of the RS port is further distributed separately in the frequency domain or time domain.

In this embodiment, the message further maps CSI-RS ports in different CSI-RS transmission periods or different frequency resource regions by multiple groups of antenna units, and multiple groups of antenna units and CSI-RS ports. It is shown that the group mapping is shifted periodically or randomly as described in the first embodiment.

In this embodiment, the message indicating the CSI-RS port and antenna unit mapping received from the eNB 700 is configured by RRC signaling and / or DCI signaling, and the message is a common search space or UE-specific search. -Some fields of DCI signaling in any of the spaces can be reused.

In this embodiment, the mapping instructions for CSI-RS ports and antenna units are represented by coordinates or crosspoint indexes.

In another embodiment of the present disclosure, the receiving unit 1101 is configured to receive a message from the eNB 700, the message being such that one group of antenna units has a first CSI-RS transmission period or a first frequency resource. Indicates that the CSI-RS port is mapped in the region, and that another group of antenna units maps the CSI-RS port in the second CSI-RS transmission period or the second frequency resource domain, within each group. Antenna units are separately distributed in the frequency domain or time domain.

In a further embodiment of the present disclosure, the receiving unit 1101 is configured to receive a message from the eNB 700, which message that one group of antenna units maps some CSI-RS ports in the resource block. As shown, its resource blocks are sparsely selected in certain flatter region channels for mapping antenna units and CSI-RS ports.

In a further embodiment of the present disclosure, resource blocks are selected at intervals in the frequency domain.

In addition, the UE 1100 according to the present disclosure further executes various programs to process various data, and various processing by the CPU (central processing unit) 1110 and the CPU 1110 for controlling the operation of each unit in the UE 1100. ROM (read-only memory) 1113 for storing various programs required to execute control, RAM (random) for storing intermediate data temporarily created by the processing and control procedures by the CPU 1110 Access memory) 1115 and / or a storage device 1117 for storing various programs, data, etc. may be included. The above-mentioned receiving unit 1101, CPU 1110, ROM 1113, RAM 1115 and / or storage device 1117 and the like are interconnected via data and / or command bus 1120, and signals can be transferred one after another.

Each unit as described above does not limit the scope of this disclosure. According to one embodiment of the present disclosure, the function of any or combination of the above-mentioned receiving units 1101 may also be implemented by functional software in combination with the above-mentioned CPU 1110, ROM 1113, RAM 1115 and / or storage device 1117 and the like.

In the aforementioned embodiments of the present disclosure, each antenna unit will have a relatively fair opportunity for transmission of the CSI-RS signal or a fairly good channel estimation performance.

FIG. 12 is a flow chart of a method of mapping the antenna unit to the CSI-RS port according to the third embodiment of this embodiment.

As shown in FIG. 12, the method starts in step S1201. In step S1201, one group of antenna units in the antenna array is selected to map the CSI-RS ports in the first CSI-RS transmission period or the first frequency resource region. In step S1202, another group of antenna units in the antenna array is selected to map the CSI-RS ports in the second CSI-RS transmission period or the second frequency resource region. In this embodiment, steps S1201 and S1202 can be performed by the mapping unit 701 of the eNB 700 of the present disclosure.

In this embodiment, one part of the CSI-RS port that maps to the antenna unit reflects the first channel vector, and another part of the CSI-RS port that maps to the antenna unit is the first channel. It reflects a second channel vector that is orthogonal or quasi-orthogonal to the vector.

In this embodiment, the portion of the CSI-RS port that reflects the first channel vector is further distributed separately in the frequency domain or time domain, and / or the CSI- that reflects the second channel vector. The other part of the RS port is further distributed separately in the frequency domain or time domain.

In this embodiment, multiple groups of antenna units are selected to map CSI-RS ports in different CSI-RS transmission periods or different frequency resource regions.

In this embodiment, the method further comprises transmitting a CSI-RS signal by periodically or randomly shifting the antenna units of the selected group. The steps described above can be performed by the transmission unit 702 of the eNB 700 of the present disclosure.

In this embodiment, the method further comprises configuring a message indicating the mapping of CSI-RS ports and antenna units by RRC or DCI signaling. The steps described above can be performed by the mapping unit 701 of the eNB 700 of the present disclosure. In this embodiment, the aforementioned message reuses some fields of DCI signaling, either in the common search space or in the UE-specific search space. Mapping instructions for CSI-RS ports and antenna units are represented by coordinates or crosspoint indexes. Multiple antenna units can be arranged in an 8x8 antenna array and the number of CSI-RS ports may be less than 40.

FIG. 13 is a flow chart of a method of mapping the antenna unit to the CSI-RS port according to the second embodiment of this embodiment.

As shown in FIG. 13, in step S1301, one group of antenna units is mapped to the CSI-RS port in the first CSI-RS transmission period or the first frequency resource domain, and another of the antenna units. Groups are mapped to CSI-RS ports in the second CSI-RS transmission period or in the second frequency domain, where the antenna units within each group are distributed separately in the frequency domain or time domain. In this embodiment, step S1301 can be performed by the mapping unit 701 of the eNB 700 of the present disclosure.

In this embodiment, one part of the CSI-RS port that maps to the antenna unit reflects the first channel vector, and another part of the CSI-RS port that maps to the antenna unit is the first channel. It reflects a second channel vector that is orthogonal or quasi-orthogonal to the vector.

In this embodiment, the portion of the CSI-RS port that reflects the first channel vector is further distributed separately in the frequency domain or time domain, and / or the CSI- that reflects the second channel vector. The other part of the RS port is further distributed separately in the frequency domain or time domain.

In this embodiment, multiple groups of antenna units are selected to map CSI-RS ports in different CSI-RS transmission periods or different frequency resource regions.

In this embodiment, the method further comprises transmitting a CSI-RS signal by periodically or randomly shifting the antenna units of the selected group. The steps described above can be performed by the transmission unit 702 of the eNB 700 of the present disclosure.

In this embodiment, the method further comprises configuring a message indicating the mapping of CSI-RS ports and antenna units by RRC or DCI signaling. The steps described above can be performed by the mapping unit 701 of the eNB 700 of the present disclosure. In this embodiment, the aforementioned message reuses some fields of DCI signaling, either in the common search space or in the UE-specific search space.

FIG. 14 is a flow chart of a method of mapping an antenna unit to a CSI-RS port according to a third embodiment of this embodiment.

As shown in FIG. 14, in step S1401, a group of antenna units is selected to map some CSI-RS ports in the resource block, where the resource blocks are antenna units and CSI-RS ports. Sparsely selected in a particular region channel that is flatter for mapping. In this embodiment, step S1401 can be performed by the mapping unit 701 of the eNB 700 of the present disclosure.

In this embodiment, resource blocks are selected at intervals in the frequency domain.

The aforementioned examples of the present disclosure are merely exemplary, and their particular structure and operation does not limit the scope of the present disclosure. One of ordinary skill in the art can recombin the different parts and behaviors of each of the aforementioned embodiments to create new implementations that are equivalent to the concepts of the present disclosure.

The embodiments of the present disclosure can be implemented by hardware, software, and firmware, or a combination thereof, and the method of implementation does not limit the scope of the present disclosure.

The connection relationships between the respective functional elements (units) in the embodiments of the present disclosure do not limit the scope of the present disclosure, and one or more functional elements or units include or connect to any other functional element. can do.

Although some embodiments of the present disclosure have been shown and described with the accompanying drawings described above, modifications and amendments that also apply to the claims of the present disclosure and their equivalents are the principles and intent of the present disclosure. It will be appreciated by those skilled in the art that these examples can be made without departing from.

Claims (10)

By combining multiple CSI-RS resource groups, each of which has a first number of CSI-RS ports, and mapping them within the same physical resource block, more CSI-RS ports than the first number can be obtained. The processing unit to be set and
A transmitter that transmits CSI-RS to one user using the set CSI-RS port, and a transmitter.
Have,
The processing unit includes a group of antenna units in which the first number of first CSI-RS ports are arranged in the first CSI-RS transmission period or the first frequency resource region, and the first. A number of second CSI-RS ports set up with other groups of antenna units, which are located in the second CSI-RS transmission period or in the second frequency resource region.
Base station equipment. The first number is eight and the number of configured CSI-RS ports is 16.
The base station apparatus according to claim 1. One of the plurality of CSI-RS resource groups reflects a vertical antenna, and the other one of the plurality of CSI-RS resource groups reflects a horizontal antenna.
The base station apparatus according to claim 1 or 2. The transmitter transmits information about the configured CSI-RS port by RRC signaling or DCI signaling.
The base station apparatus according to any one of claims 1 to 3. The first CSI-RS port reflects a first channel vector, and the second CSI-RS port reflects a second channel vector that is orthogonal or quasi-orthogonal to the first channel vector.
The base station apparatus according to any one of claims 1 to 4. The first CSI-RS port reflecting the first channel vector and / or the second CSI-RS port reflecting the second channel vector are distributed separately in the frequency domain or the time domain. ,
The base station apparatus according to claim 5. A group of the antenna units in which the first CSI-RS port and the second CSI-RS port are arranged, which differ in the CSI-RS transmission period or the frequency resource area, is set.
The base station apparatus according to any one of claims 1 to 6. The transmitter transmits information regarding the arrangement of the first CSI-RS port and the second CSI-RS port in the group of the antenna units by RRC signaling or DCI signaling.
The base station apparatus according to any one of claims 1 to 7. The information indicates the placement of the first CSI-RS port and the second CSI-RS port in the group of antenna units by coordinates or crosspoint indexes.
The base station apparatus according to claim 8. By combining multiple CSI-RS resource groups, each of which has a first number of CSI-RS ports, and mapping them within the same physical resource block, more CSI-RS ports than the first number can be obtained. Set,
Send CSI-RS to one user using the configured CSI-RS port.
It ’s a communication method.
A group of antenna units and a second CSI of the first number, wherein the first number of first CSI-RS ports are located in the first CSI-RS transmission period or the first frequency resource region. -RS port sets up with other groups of antenna units, located in the second CSI-RS transmission period or in the second frequency resource area.
Communication method.

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