WO2019082279A1

WO2019082279A1 - Terminal device, base station device, wireless communication system, and wireless communication method

Info

Publication number: WO2019082279A1
Application number: PCT/JP2017/038386
Authority: WO
Inventors: 三夫小林
Original assignee: 富士通株式会社
Priority date: 2017-10-24
Filing date: 2017-10-24
Publication date: 2019-05-02
Also published as: JPWO2019082279A1

Abstract

This terminal device includes: an allocation unit which allocates transmission power to an uplink signal including first data and an uplink signal including second data having a higher priority than the first data; a transmission control unit which stops transmission of the uplink signal including the first data, when the transmission power allocated to the uplink signal including the first data does not reach a prescribed level; a buffer management unit which stores, to a buffer, an ACK which is the first data indicating content that data reception in a downlink line is successful, when the transmission stops; and a transmission unit which transmits a buffer state report in which the ACK reports the content stored in the buffer to suspend a retransmission control for the data by using the uplink signal including the second data.

Description

Terminal apparatus, base station apparatus, wireless communication system and wireless communication method

The present invention relates to a terminal device, a base station device, a wireless communication system, and a wireless communication method.

In current networks, traffic of mobile terminals (smart phones and feature phones) occupies most of network resources. Also, traffic used by mobile terminals tends to expand in the future.

On the other hand, in line with the development of the IoT (Internet of things) service (for example, a traffic system, a smart meter, a monitoring system of a device, etc.), it is expected to respond to services having various requirements. Therefore, in the next-generation (for example, 5G (5th generation mobile communication)) communication standard, in addition to the standard technology of 4G (4th generation mobile communication), further higher data rate, larger capacity, lower delay Technologies to realize this technology are expected. As for the next-generation communication standard, technical studies are in progress at a working group of 3GPP (for example, TSG-RAN WG1, TSG-RAN WG2, etc.).

As described above, in order to support a wide variety of services, 5G is classified into eMBB (Enhanced Mobile Broad Band), Massive MTC (Machine Type Communications), and URLLC (Ultra-Reliable and Low Latency Communication). Support for many use cases is envisioned.

Among them, URLLC is the most difficult use case to realize. First of all, there is a demand for ultra-high reliability in which the error rate in the wireless section is on the order of 10 ^-5 . One way to achieve ultra-high reliability is to increase the amount of resources used to make data redundant. However, because radio resources are limited, it is not possible to increase the use resources indefinitely.

With regard to low delay, URLLC aims to set the delay in the radio section of the user plane in uplink and downlink to 0.5 ms. This is a high demand of less than 1/10 of 4G wireless system LTE (Long Term Evolution). In URLLC, it is desirable to simultaneously satisfy the two requirements of ultra-reliability and low delay as described above.

Further, in 5G, it is desired that ultra-reliable low delay communication data (URLLC data) and other data (for example, eMBB data etc.) can be simultaneously supported by the same carrier. In order to realize this, there has been proposed a technique for individually allocating transmission power to ultra-reliable low-delay communication data (URLLC data) and other data (for example, eMBB data etc.).

By the way, when the terminal apparatus simultaneously transmits eMBB data and URLLC data to the base station apparatus, it is conceivable that transmission power is preferentially allocated to URLLC data having higher priority. For this reason, the transmission power allocated to eMBB data may decrease, and the base station apparatus may fall below a predetermined level for correctly receiving (decoding) eMBB data. The eMBB data includes, for example, ACK (ACKnowledgement) / NACK (Negative ACKnowledgement) for controlling retransmission of data on the downlink in a hybrid automatic repeat request (HARQ: Hybrid Automatic Repeat request).

When an ACK transmitted as eMBB data in uplink is not correctly received (decoded) in the base station apparatus due to a decrease in transmission power of eMBB data, the base station apparatus fails in reception (decoding) of data in downlink. It is determined that the data has been retransmitted. However, such retransmission of data is useless retransmission that should not occur when the transmission power of eMBB data has reached a predetermined level.

An object of the disclosed technology is to provide a terminal apparatus, a base station apparatus, a wireless communication system, and a wireless communication method capable of suppressing unnecessary retransmission in downlink.

In one aspect, the terminal device disclosed in the present application allocates an uplink signal including first data and an allocation unit that allocates transmission power to an uplink signal including second data having a higher priority than the first data; A transmission control unit for stopping transmission of the uplink signal including the first data when the transmission power allocated to the uplink signal including the first data does not reach a predetermined level; and the transmission is stopped A buffer management unit that stores an ACK, which is the first data indicating that reception of data in the downlink is successful, in a buffer, and reports that the ACK is stored in the buffer to control retransmission of the data. And a transmission unit for transmitting a buffer status report for holding the second data using the upstream signal including the second data.

According to one aspect of the terminal apparatus disclosed in the present application, it is possible to suppress unnecessary retransmission in the downlink.

FIG. 1 is a diagram illustrating an example of a configuration of a wireless communication system according to a first embodiment. FIG. 2 is a block diagram illustrating an exemplary configuration of a terminal device according to the first embodiment. FIG. 3 is a diagram of an example of the buffer management unit according to the first embodiment. FIG. 4A is a diagram showing a specific example (No. 1) of the configuration of resources to be subjected to BSR insertion. FIG. 4B is a diagram showing a specific example (No. 2) of the configuration of resources to be subjected to BSR insertion. FIG. 4C is a diagram showing a specific example (No. 3) of the configuration of resources to be subjected to BSR insertion. FIG. 4D is a diagram showing a specific example (No. 4) of the configuration of resources to be subjected to BSR insertion. FIG. 5 is a block diagram of an exemplary configuration of a base station apparatus according to the first embodiment. FIG. 6 is a sequence diagram illustrating an example of a wireless communication method according to the first embodiment. FIG. 7 is a flowchart illustrating an example of the ACK buffering operation according to the first embodiment. FIG. 8 is a flowchart of an example of the retransmission control operation according to the first embodiment. FIG. 9 is a block diagram illustrating an exemplary configuration of a terminal device according to a second embodiment. FIG. 10 is a block diagram of a configuration example of a base station apparatus according to a second embodiment. FIG. 11 is a sequence diagram illustrating an example of a wireless communication method according to the second embodiment. FIG. 12 is a flowchart of an example of the retransmission control operation according to the second embodiment.

Hereinafter, embodiments of a terminal apparatus, a base station apparatus, a wireless communication system, and a wireless communication method disclosed in the present application will be described in detail based on the drawings. The disclosed technology is not limited by the embodiments. In addition, the same reference numerals are given to the configurations having the same functions in the respective embodiments, and the overlapping description will be omitted.

FIG. 1 is a diagram illustrating an example of a configuration of a wireless communication system according to a first embodiment. The wireless communication system illustrated in FIG. 1 includes a terminal device 100 and a base station device 200. The terminal device 100 and the base station device 200 transmit and receive data such as eMBB data and URLLC data in uplink and downlink, for example. The uplink between the terminal device 100 and the base station 200 includes an uplink for eMBB data (hereinafter referred to as "eMBB uplink") and an uplink for URLLC data (hereinafter referred to as "URLLC uplink"). And is included. In 5G, URLLC data is expected to be transmitted with lower delay than eMBB data, and has higher priority than eMBB data. The eMBB data is an example of the first data, and the URLLC data is an example of the second data.

When the terminal device 100 simultaneously transmits eMBB data and URLLC data in the eMBB uplink and URLLC uplink, it allocates transmission power to an uplink signal including eMBB data and an uplink signal including URLLC data. Hereinafter, an uplink signal including eMBB data is referred to as an “eMBB transmission signal”, and an uplink signal including URLLC data is referred to as a “URLLC transmission signal”. The eMBB data transmitted in the eMBB uplink includes ACK / NACK for controlling retransmission of data in the downlink. Since the URLLC data has higher priority than the eMBB data such as ACK / NACK, the terminal device 100 preferentially allocates the transmission power to the uplink signal including the URLLC data, that is, the URLLC transmission signal. Therefore, it is assumed that the transmission power allocated to the eMBB transmission signal does not reach a predetermined level for correctly receiving (decoding) the eMBB data in the base station apparatus 200. In this case, the terminal device 100 stops transmission of the eMBB transmission signal, and stores, in the buffer in the terminal device 100, an ACK, which is eMBB data indicating that reception of data on the downlink is successful, among eMBB data. Then, the terminal device 100 transmits a buffer status report (BSR: Buffer Statement Report) that reports that the ACK is stored in the buffer using the URLLC transmission signal, and retransmits the data according to the ACK to the base station device 200. Hold control

Further, the terminal device 100 receives, from the base station device 200 holding retransmission control, hold information indicating that retransmission control is held. Then, the terminal device 100 reads the ACK from the buffer according to the received hold information, and transmits an uplink signal including the ACK, thereby causing the base station device 200 to resume retransmission control.

Base station apparatus 200 receives the BSR transmitted from terminal apparatus 100, and suspends retransmission control for data in downlink according to BSR. Also, the base station apparatus 200 receives an uplink signal including an ACK from the terminal apparatus 100, and resumes retransmission control of data according to the ACK.

Thereby, when the transmission power allocated to eMBB data runs short, retransmission control in base station apparatus 200 can be suspended. As a result, it is possible to suppress unnecessary retransmissions that would otherwise occur in the downlink.

FIG. 2 is a block diagram illustrating an exemplary configuration of the terminal device 100 according to the first embodiment. The terminal device 100 illustrated in FIG. 2 includes a processor 100a, a wireless transmission unit 100b, and a wireless reception unit 100c.

The processor 100a includes, for example, a central processing unit (CPU), a field programmable gate array (FPGA), or a digital signal processor (DSP), and centrally controls the entire terminal device 100. Specifically, the processor 100a includes a path loss measurement unit 101, a transmission power assignment unit 102, a transmission control unit 103, a buffer management unit 104, an eMBB transmission signal generation unit 105, a URLLC transmission signal generation unit 106, and a BSR insertion unit 107. . The processor 100 a further includes a PDCCH (Physical Downlink Control Channel) decoding unit 108, a DCI (Downlink Control Information) determination unit 109, and a PDSCH (Physical Downlink Shared Channel) decoding unit 110. Also, the processor 100a includes an ACK / NACK generation unit 111.

The path loss measurement unit 101 receives an input of a reception signal from the wireless reception unit 100 c. The received signal includes the reference signal transmitted from the base station apparatus 200 to the downlink. The path loss measurement unit 101 measures the received power of the reference signal, and measures the path loss measurement value by subtracting the measured received power from the transmission power of the predetermined reference signal. The path loss measurement unit 101 outputs the path loss measurement value to the transmission power assignment unit 102.

Transmission power allocation section 102 allocates transmission power to the eMBB transmission signal transmitted to base station apparatus 200 in the eMBB uplink and to the URLLC transmission signal transmitted to base station apparatus 200 in the URLLC uplink. That is, the transmission power allocation unit 102 performs, for example, the calculation shown in the following equation (1) for the subframe i of the cell c, and allocates the transmission power P _{PUSCH, c, URLLC} (i) to the URLLC transmission signal.

P _{CMAX, c} (i) in the equation (1) is the maximum transmission power that can be used in the URLLC uplink and the eMBB uplink in the terminal device 100. M _{PUSCH, c, URLLC} (i) is the bandwidth allocated to the URLLC uplink. P _{O — PUSCH, c, URLLC} (j) is the target received power. α _{c, URLLC} (j) is a path loss compensation coefficient. PL _c is a path loss measurement. Δ _{TF, c, URLLC} (i) is a correction value based on the coding rate / modulation scheme. f _{c, URLLC} (i) is a TPC (Transmission Power Control) command value. M _{PUSCH, c, URLLC} (i), P _O _{_ PUSCH, c, URL} _LC (j), α _{c, URL LC} (j), Δ _{TF, c, URL LC} (i) and f _{c, URL LC} (i) are power The information is notified from the base station apparatus 200 to the terminal apparatus 100 as information.

Subsequently, the transmission power allocation unit 102 performs, for example, the following equation (2) on the subframe i of the cell c, and transmits the transmission power P _{PUSCH, c, eMBB} (i) to the eMBB transmission signal (that is, Assign to ACK / NACK).

P _{required_PUSCH, c, eMBB} (i) in equation (2) is the target transmission power required to correctly receive (decode) eMBB data in base station apparatus 200, as shown in equation (3) below. Expressed in

M _{PUSCH, c, eMBB} (i) in equation (3) is the bandwidth allocated to the eMBB uplink. _{PO_PUSCH, c, eMBB} (j) is the target received power. α _{c, eMBB} (j) is a path loss compensation coefficient. PL _c is a path loss measurement. Δ _{TF, c, eMBB} (i) is a correction value based on a coding rate / modulation scheme. f _{c, eMBB} (i) are TPC command values. M _{PUSCH, c, eMBB} (i), _{PO_PUSCH, c, eMBB} (j), α _{c, eMBB} (j), Δ _{TF, c, eMBB} (i) and f _{c, eMBB} (i) The information is notified from the base station apparatus 200 to the terminal apparatus 100 as information.

Transmission control section 103 transmits the eMBB transmission signal when transmission power P _{PUSCH, c, eMBB} (i) allocated to eMBB transmission signal (that is, ACK / NACK) by transmission power allocation section 102 does not reach a predetermined level. Stop. That is, transmission control section 103 determines whether or not transmission power P _{PUSCH, c, eMBB} (i) has reached a predetermined level, using the following equation (4).

P _{threshold, c, eMBB} (i) in the equation (4) is a threshold for determination, and may be held in advance in the terminal device 100 or may be notified from the base station device 200 by predetermined signaling. .

Transmission control section 103 determines that transmission power P _{PUSCH, c, eMBB} (i) has not reached a predetermined level when the condition of equation (4) is satisfied. Then, the transmission control unit 103 outputs, to the eMBB transmission signal generation unit 105, a DTX (Discontinuous Transmission) control signal for stopping the output of the upstream signal (that is, the eMBB transmission signal) including the eMBB data. Then, the transmission control unit 103 sets “Enable”, which indicates that the ACK is to be stored in the buffer, in the buffering control signal, and outputs the buffering control signal to the buffer management unit 104. Furthermore, the transmission control unit 103 outputs, to the BSR insertion unit 107, a BSR that reports that the ACK has been stored in the buffer, that is, a BSR in which "true" is set.

On the other hand, when the condition of Expression (4) is not satisfied, the transmission control unit 103 determines that the transmission power P _{PUSCH, c, eMBB} (i) has reached a predetermined level. In this case, the transmission control unit 103 does not output the above DTX control signal. Then, the transmission control unit 103 sets “Disable”, which indicates that the ACK is not stored in the buffer, in the buffering control signal, and outputs the buffering control signal to the buffer management unit 104. Furthermore, the transmission control unit 103 outputs, to the BSR insertion unit 107, a BSR that reports that the ACK is not stored in the buffer, that is, a BSR in which "false" is set.

The buffer management unit 104 stores the ACK in the buffer when the transmission of the eMBB transmission signal is stopped. Also, buffer management section 104 reads ACK from the buffer when transmission power P _{PUSCH, c, eMBB} (i) allocated to the eMBB transmission signal reaches a predetermined level and hold information is received from base station apparatus 200. . When the transmission of the eMBB transmission signal is not stopped, the buffer management unit 104 outputs the ACK / NACK generated by the ACK / NACK generation unit 111 to the eMBB transmission signal generation unit 105.

For example, as illustrated in FIG. 3, the buffer management unit 104 includes a buffer 121, a selection unit 122, and a buffer control unit 123. FIG. 3 is a diagram illustrating an example of the buffer management unit 104 according to the first embodiment.

The buffer 121 temporarily stores the ACK generated by the ACK / NACK generation unit 111 or reads the ACK under the control of the buffer control unit 123.

The selection unit 122 outputs the ACK read from the buffer 121 or the ACK / NACK generated by the ACK / NACK generation unit 111 to the eMBB transmission signal generation unit 105 under the control of the buffer control unit 123. Choose as.

The buffer control unit 123 receives an input of a buffering control signal from the transmission control unit 103. The buffer control unit 123 receives an input of the retransmission hold signal from the DCI determination unit 109 described later. The retransmission hold signal is a signal indicating whether or not retransmission control is suspended in the base station apparatus 200. When retransmission control is suspended, "Enable" is set, and retransmission control is not suspended. "Disable" is set. The buffer control unit 123 controls the buffer 121 and the selection unit 122 based on the buffering control signal and the retransmission hold signal.

That is, when the buffering control signal is “Enable” and the retransmission hold signal is “Disable”, the buffer control unit 123 stores the ACK in the buffer 121 and cancels the selection by the selection unit 122. In addition, when the buffering control signal is “Enable” and the retransmission hold signal is “Enable”, the buffer control unit 123 cancels the reading of the ACK previously stored in the buffer 121, and the selection unit 122 Cancel selection. Also, when the buffering control signal is “Disable” and the retransmission hold signal is “Enable”, the buffer control unit 123 reads the ACK from the buffer 121 and selects the ACK read from the buffer 121. Select to. Thereby, the ACK read from the buffer 121 is output to the eMBB transmission signal generation unit 105. Also, when the buffering control signal is “Disable” and the retransmission hold signal is “Disable”, the buffer control unit 123 causes the selection unit 122 to select the ACK / NACK from the ACK / NACK generation unit 111. Thus, the ACK / NACK from the ACK / NACK generation unit 111 is output to the eMBB transmission signal generation unit 105.

It returns to the explanation of FIG. The eMBB transmission signal generation unit 105 generates an eMBB transmission signal to be transmitted to the base station apparatus 200. That is, the eMBB transmission signal generation unit 105 encodes and modulates the ACK read from the buffer by the buffer management unit 104 or the ACK / NACK generated by the ACK / NACK generation unit 111 as eMBB data. Then, the eMBB transmission signal generation unit 105 outputs the generated eMBB transmission signal to the wireless transmission unit 100b. However, according to the DTX control signal output from transmission control section 103, eMBB transmission signal generation section 105 outputs the eMBB transmission signal when transmission power P _{PUSCH, c, eMBB} (i) has not reached a predetermined level. Stop.

The URLLC transmission signal generation unit 106 generates a URLLC transmission signal to be transmitted to the base station apparatus 200. That is, the URLLC transmission signal generation unit 106 encodes and modulates uplink URLLC data. Then, the URL LC transmission signal generation unit 106 outputs the generated URL LC transmission signal to the wireless transmission unit 100 b.

The BSR insertion unit 107 inserts the BSR output from the transmission control unit 103 into the URLLC transmission signal. Accordingly, the URLLC transmission signal in which the BSR is inserted is output to the wireless transmission unit 100b, and the BSR is transmitted to the base station apparatus 200 using the URLLC transmission signal in the wireless transmission unit 100b.

Here, the BSR insertion by the BSR insertion unit 107 will be specifically described. FIG. 4A is a diagram showing a specific example (No. 1) of the configuration of resources to be subjected to BSR insertion. FIG. 4A shows a PUSCH (Physical Uplink Shared Channel) resource of a URLLC transmission signal, and the PUSCH has DRS (Demodulation Reference Signal) 501 and 502 in two symbol areas arranged in the time axis direction. The BSR 601 is inserted into the symbol region adjacent to the DRS 501 having the smaller symbol number from the rear of the time axis, of the two

DRS

501 and 502 in the PUSCH of the URLLC transmission signal.

FIG. 4B is a diagram showing a specific example (No. 2) of the configuration of resources to be subjected to BSR insertion. FIG. 4B shows the PUSCH resource of the URLLC transmission signal, and the PUSCH has

DRSs

501 and 502 in two symbol areas arranged in the time axis direction. The BSR 601 is inserted into the symbol area adjacent to the DRS 502 having the larger symbol number from the front of the time axis, of the two DRSs 501 and 502 in the PUSCH of the URLLC transmission signal.

FIG. 4C is a diagram showing a specific example (No. 3) of the configuration of resources to be subjected to BSR insertion. FIG. 4C shows the PUSCH resources of the URLLC transmission signal, and the PUSCH has the DRS 503 in one symbol area arranged in the time axis direction. The BSR 601 is inserted into the symbol area adjacent to the DRS 503 from the back of the time axis on the PUSCH of the URLLC transmission signal.

FIG. 4D is a diagram showing a specific example (No. 4) of the configuration of resources to be subjected to BSR insertion. FIG. 4D shows the PUSCH resources of the URLLC transmission signal, and the PUSCH has the DRS 503 in one symbol region arranged in the time axis direction. The BSR 601 is inserted into the symbol area adjacent to the DRS 503 from the front of the time axis on the PUSCH of the URLLC transmission signal.

It returns to the explanation of FIG. The PDCCH decoding unit 108 receives an input of the reception signal from the wireless reception unit 100 c. The received signal includes a signal of PDCCH transmitted from the base station apparatus 200 to the downlink. The PDCCH signal includes downlink control information (DCI). The PDCCH decoding unit 108 demodulates and decodes the PDCCH signal to obtain DCI. Then, PDCCH decoding section 108 outputs DCI to DCI determination section 109.

The DCI determination unit 109 receives an input of DCI from the PDCCH decoding unit 108. The DCI determination unit 109 determines the processing content in the PDSCH decoding unit 110 according to the content of the DCI, and outputs a retransmission hold signal to the buffer management unit 104. That is, when DCI is "new information" indicating that the data transmitted from the base station apparatus 200 to the downlink is new data, DCI determination section 109 performs PDSCH decoding for demodulation and decoding according to the new data. It instructs the part 110. At this time, the DCI determination unit 109 sets “Disable” in the retransmission hold signal to be output to the buffer management unit 104. Further, DCI determination section 109 performs PDSCH decoding for demodulation and decoding according to retransmission data, when DCI is “retransmission information” indicating that data transmitted from base station apparatus 200 to the downlink is retransmission data. It instructs the part 110. At this time, the DCI determination unit 109 sets “Disable” in the retransmission hold signal to be output to the buffer management unit 104. Further, when the DCI is “pending information” indicating that the retransmission control in the base station apparatus 200 is suspended, the DCI determination unit 109 stops the processing in the PDSCH decoding unit 110 and outputs it to the buffer management unit 104. Set "Enable" to the retransmission hold signal.

The PDSCH decoding unit 110 receives an input of the reception signal from the wireless reception unit 100c. The received signal includes a PDSCH signal transmitted from the base station apparatus 200 to the downlink. The PDSCH decoding unit 110 demodulates and decodes the PDSCH signal according to an instruction from the DCI determination unit 109 to acquire data. Then, the PDSCH decoding unit 110 determines whether the data has been decoded normally, and notifies the ACK / NACK generation unit 111 of the success or failure of the data decoding. However, when the DCI determination unit 109 instructs the PDSCH decoding unit 110 to stop the process, the PDSCH decoding unit 110 stops the process.

The ACK / NACK generation unit 111 receives a notification of success or failure of data decoding from the PDSCH decoding unit 110. Then, the ACK / NACK generation unit 111 generates an ACK indicating that the decoding (reception) of data has succeeded or a NACK indicating that the decoding (reception) of data has failed, and manages the generated ACK / NACK as a buffer. Output to unit 104.

The wireless transmission unit 100b performs wireless transmission processing such as D / A (Digital / Analog) conversion and up-conversion on the transmission signals output from the processor 100a, that is, the eMBB transmission signal and the URLLC transmission signal. Then, the wireless transmission unit 100b transmits the eMBB transmission signal and the URLLC transmission signal via the antenna. At this time, the BSR insertion unit 107 inserts a BSR that reports that ACK is not stored in the buffer in the URLLC transmission signal. However, when the output of the eMBB transmission signal by the processor 100a is stopped, the wireless transmission unit 100b transmits only the URLLC transmission signal. At this time, in the URLLC transmission signal, a BSR that reports that the ACK has been stored in the buffer is inserted. That is, the wireless transmission unit 100b transmits, using the URLLC transmission signal, a BSR that reports that the ACK has been stored in the buffer.

The wireless reception unit 100c receives a signal via an antenna, and performs wireless reception processing such as down conversion and A / D (Analog / Digital) conversion on the received signal. Then, the wireless reception unit 100c outputs the received signal to the path loss measurement unit 101, the PDCCH decoding unit 108, and the PDSCH decoding unit 110.

FIG. 5 is a block diagram showing a configuration example of the base station apparatus 200 according to the first embodiment. The base station apparatus 200 illustrated in FIG. 5 includes a processor 200a, a wireless transmission unit 200b, and a wireless reception unit 200c.

The processor 200a includes, for example, a CPU, an FPGA, or a DSP, and centrally controls the entire base station apparatus 200. Specifically, the processor 200a includes an eMBB data decoding unit 201, a URLLC data decoding unit 202, a BSR extraction unit 203, and a retransmission control unit 204. Further, the processor 200a includes a PDCCH generation unit 205, a power information management unit 206, a PDSCH generation unit 207, and a retransmission buffer 208.

The eMBB data decoding unit 201 receives an input of a reception signal from the wireless reception unit 200c. The received signal includes the eMBB transmission signal transmitted from the terminal device 100 in the eMBB uplink. The eMBB transmission signal is not always included in the reception signal because the transmission of the eMBB transmission signal is stopped by the terminal device 100 when the transmission power allocated to the eMBB transmission signal is insufficient. The eMBB data decoding unit 201 demodulates and decodes the eMBB transmission signal included in the received signal to obtain eMBB data (that is, ACK / NACK). The eMBB data decoding unit 201 outputs DTX indicating that ACK / NACK or neither ACK nor NACK is obtained to the retransmission control unit 204 as a result of decoding (reception) of eMBB data.

The URLLC data decoding unit 202 receives an input of the reception signal from the wireless reception unit 200c. The received signal includes the URLLC transmission signal transmitted from the terminal device 100 in the URLLC uplink. The URLLC data decoding unit 202 demodulates and decodes the URLLC transmission signal contained in the received signal to acquire URLLC data.

The BSR extraction unit 203 extracts a BSR from the URLLC transmission signal demodulated and decoded by the URLLC data decoding unit 202, and outputs the extracted BSR to the retransmission control unit 204.

The retransmission control unit 204 receives an input of the decoding (reception) result of the eMBB data from the eMBB data decoding unit 201. Retransmission control section 204 receives an input of BSR from BSR extraction section 203. The retransmission control unit 204 suspends the retransmission control for the terminal device 100 based on the decoding result of the eMBB data and the BSR.

Specifically, when “true” is set in BSR, that is, when ACK is stored in the buffer of the terminal device 100, the retransmission control unit 204 does not depend on the decoding result of the eMBB data. Suspend retransmission control for 100. That is, retransmission control section 204 outputs “pending information” indicating that retransmission control to terminal apparatus 100 is suspended as DCI to PDCCH generating section 205, and causes PDSCH generating section 207 to stop output of PDSCH signal. To direct.

Also, when “false” is set in BSR, that is, when ACK is not stored in the buffer of the terminal device 100, the retransmission control unit 204 executes retransmission control according to the decoding result of eMBB data. That is, when the decoding result of the eMBB data is ACK, the retransmission control unit 204 outputs “new information” indicating that the data to be transmitted to the downlink is new data as DCI to the PDCCH generation unit 205, The new data is output to PDSCH generation section 207.

On the other hand, if the decoding result of the eMBB data is NACK or DTX, retransmission control section 204 outputs “retransmission information” indicating that the data to be transmitted to the downlink is retransmission data as DCI to PDCCH generation section 205 And instructs the PDSCH generation unit 207 to retransmit retransmission data.

The PDCCH generation unit 205 receives an input of DCI from the retransmission control unit 204. The PDCCH generation unit 205 encodes and modulates the DCI to generate a signal of the PDCCH including the DCI. The PDCCH generation unit 205 outputs the signal of the PDCCH including the DCI to the radio transmission unit 200b as a transmission signal.

The power information management unit 206 holds power information used for calculating transmission power to be allocated to the eMBB transmission signal transmitted from the terminal device 100 in the eMBB uplink and the URLLC transmission signal transmitted from the terminal device 100 in the URLLC uplink. Do.

The PDSCH generation unit 207 encodes and modulates the new data input from the retransmission control unit 204 to generate a PDSCH signal including the new data. The PDSCH generation unit 207 outputs the signal of the PDSCH including the new data as a transmission signal to the wireless transmission unit 200b.

Also, when instructed by the retransmission control unit 204 to retransmit retransmission data, the PDSCH generation unit 207 acquires data to be retransmitted from among the data stored in the retransmission buffer 208. Then, the PDSCH generation unit 207 encodes and modulates the acquired data to generate a PDSCH signal including retransmission data. The PDSCH generation unit 207 outputs the signal of PDSCH including the retransmission data as a transmission signal to the radio transmission unit 200b.

Further, the PDSCH generation unit 207 stops the output of the PDSCH signal according to the control of the retransmission control unit 204.

The retransmission buffer 208 is a temporary storage area of the PDSCH signal output from the PDSCH generation unit 207. When the PDSCH signal output from the PDSCH generation unit 207 is a PDSCH signal including new data, the retransmission buffer 208 discards the PDSCH signal stored in the past, and stores the current PDSCH signal. In addition, when the PDSCH signal output from the PDSCH generation unit 207 is a PDSCH signal including retransmission data, or when the output of the PDSCH signal from the PDSCH generation unit 207 is stopped, the PDSCH stored in the past Keep the signal of

The wireless transmission unit 200b performs, for example, wireless transmission processing such as D / A conversion and upconversion on the transmission signal output from the processor 200a, that is, the signal of PDSCH including new data or the signal of PDSCH including retransmission data. Apply. Then, the wireless transmission unit 200b transmits a transmission signal via the antenna.

The wireless reception unit 200c receives a signal via an antenna, and performs wireless reception processing such as down conversion and A / D conversion on the received signal. Then, the wireless reception unit 200 c outputs the received signal to the eMBB data decoding unit 201 and the URLLC data decoding unit 202.

Next, a wireless communication method in the wireless communication system configured as described above will be described with reference to FIG. FIG. 6 is a sequence diagram illustrating an example of a wireless communication method according to the first embodiment.

The base station apparatus 200 transmits a signal of PDSCH including new data using the downlink (step S101). While transmission of URLLC data by the terminal device 100 has not occurred, the terminal device 100 transmits an eMBB transmission signal including ACK / NACK as eMBB data indicating success or failure of reception (decoding) of data in the downlink. Then, the base station apparatus 200 transmits new data or retransmission data according to ACK / NACK.

Then, when URLLC data is generated in the terminal device 100 (step S102), the terminal device 100 allocates transmission power to the eMBB transmission signal and the URLLC transmission signal (step S103). Since the URLLC data has higher priority than the eMBB data such as ACK / NACK, the terminal device 100 preferentially allocates the transmission power to the uplink signal including the URLLC data, that is, the URLLC transmission signal. Therefore, it is assumed that the transmission power allocated to the eMBB transmission signal does not reach a predetermined level for correctly receiving (decoding) the eMBB data in the base station apparatus 200.

In this case, the terminal device 100 stops transmission of an eMBB transmission signal including ACK / NACK as eMBB data (step S104). Then, the terminal device 100 stores an ACK, which is eMBB data indicating that reception of data on the downlink has succeeded among the eMBB data, in a buffer in the terminal device 100 (step S105). Then, the terminal device 100 inserts, into the URLLC transmission signal, a BSR that reports that the ACK has been stored in the buffer in the terminal device 100 (step S106). And the terminal device 100 transmits the said BSR using a URLLC transmission signal (step S107).

When the base station apparatus 200 receives the BSR transmitted from the terminal apparatus 100, the base station apparatus 200 suspends retransmission control for data on the downlink according to the BSR (step S108). Then, the base station apparatus 200 transmits, using a downlink, a PDCCH signal including, as DCI, “pending information” indicating that retransmission control to the terminal apparatus 100 is suspended (step S109).

When receiving the signal of the PDCCH including “pending information” as DCI, the terminal apparatus 100 reads ACK from the buffer according to “pending information” (step S110), and transmits an uplink signal including ACK (step S111).

When receiving the uplink signal including the ACK, the base station apparatus 200 resumes retransmission control for the terminal apparatus 100 (step S112). In the example of FIG. 6, in response to the ACK, the base station apparatus 200 discards the PDSCH signal stored in the past in the retransmission buffer 208, and transmits the PDSCH signal including new data using the downlink.

Next, an ACK buffering operation in the terminal device 100 will be described with reference to FIG. FIG. 7 is a flowchart illustrating an example of the ACK buffering operation according to the first embodiment.

When the buffering control signal is “Enable” and the retransmission hold signal is “Disable” (Step S121 Yes and Step S122 No), the buffer management unit 104 of the terminal device 100 stores the ACK in the buffer 121 (Step S123). ). At this time, the buffer management unit 104 cancels the selection by the selection unit 122. As a result, ACK / NACK is not output as eMBB data from the selection unit 122 to the eMBB transmission signal generation unit 105.

In addition, when the buffering control signal is “Enable” and the retransmission hold signal is “Enable” (Step S121 Yes and Step S122 Yes), the buffer control unit 123 stops reading the ACK previously stored in the buffer 121. (Step S124). At this time, the buffer management unit 104 cancels the selection by the selection unit 122. As a result, ACK / NACK is not output as eMBB data from the selection unit 122 to the eMBB transmission signal generation unit 105.

In addition, when the buffering control signal is “Disable” and the retransmission hold signal is “Enable” (Step S121 No and Step S125 Yes), the buffer control unit 123 reads ACK from the buffer 121 (Step S126). At this time, the buffer control unit 123 causes the selection unit 122 to select the ACK read from the buffer 121. Thus, the ACK read from the buffer 121 is output to the eMBB transmission signal generation unit 105, and the eMBB transmission signal generation unit 105 generates an eMBB transmission signal including the ACK as eMBB data.

Also, when the buffering control signal is “Disable” and the retransmission hold signal is “Disable” (Step S121 No and Step S125 No), the buffer control unit 123 receives ACK / NACK from the ACK / NACK generation unit 111. The selection unit 122 is made to select. Thus, the ACK / NACK from the ACK / NACK generation unit 111 is output to the eMBB transmission signal generation unit 105 (step S127).

Next, the retransmission control operation in base station apparatus 200 will be described with reference to FIG. FIG. 8 is a flowchart of an example of the retransmission control operation according to the first embodiment.

If "true" is set in BSR, that is, if ACK is stored in the buffer of the terminal apparatus 100 (step S131 Yes), the retransmission control unit 204 of the base station apparatus 200 is not concerned with the decoding result of eMBB data. Then, the retransmission control for the terminal device 100 is suspended (step S132). That is, retransmission control section 204 outputs “pending information” indicating that retransmission control to terminal apparatus 100 is suspended as DCI to PDCCH generating section 205, and causes PDSCH generating section 207 to stop output of PDSCH signal. To direct. As a result, the output of the PDSCH signal from the PDSCH generation unit 207 is stopped. Further, the PDCCH generation unit 205 generates a signal of PDCCH including “pending information”, and the signal of the PDCCH is transmitted as a transmission signal through the wireless transmission unit 200 b. The terminal device 100 that has received the signal of the PDCCH including the "pending information" reads the ACK from the buffer according to the "pending information", and transmits an uplink signal including the ACK.

In addition, when “false” is set in BSR, that is, when ACK is not stored in the buffer of terminal apparatus 100 (step S131 No), retransmission control section 204 performs retransmission control according to the decoding result of eMBB data. Run. That is, when the decoding result of the eMBB data is ACK (Yes at step S133), retransmission control section 204 uses PDCI as “new information” indicating that the data transmitted to the downlink is new data to PDCCH generation section 205. It outputs the new data to the PDSCH generation unit 207. As a result, a PDSCH signal including new data is generated in the PDSCH generation unit 207, and the signal of the PDSCH is transmitted as a transmission signal through the wireless transmission unit 200b (step S134). Furthermore, the PDCCH generation unit 205 generates a signal of PDCCH including “new information”, and the signal of the PDCCH is transmitted as a transmission signal through the wireless transmission unit 200 b.

On the other hand, when the decoding result of the eMBB data is NACK or DTX (No at step S133), the retransmission control unit 204 sets “retransmission information” indicating that the data transmitted to the downlink is retransmission data as DCI to the PDCCH generation unit It outputs to 205 and instructs the PDSCH generation unit 207 to retransmit retransmission data. As a result, a PDSCH signal including retransmission data is generated in the PDSCH generation unit 207, and the signal of the PDSCH is transmitted as a transmission signal via the wireless transmission unit 200b (step S135). Further, the PDCCH generation unit 205 generates a signal of PDCCH including “retransmission information”, and the signal of the PDCCH is transmitted as a transmission signal through the wireless transmission unit 200 b.

As described above, according to this embodiment, the terminal device stops the eMBB transmission signal when the transmission power of the eMBB transmission signal does not reach a predetermined level under the condition where uplink eMBB data and URLCC data occur simultaneously. And stores ACK, which is eMBB data, in the buffer. Then, the terminal apparatus transmits, using the URLCC transmission signal, a BSR that reports that the ACK has been stored in the buffer of the terminal apparatus, and causes the base station apparatus to suspend retransmission control for data in the downlink. Thereby, when the transmission power allocated to eMBB data runs short, retransmission control in the base station apparatus can be suspended. As a result, it is possible to suppress unnecessary retransmissions that would otherwise occur in the downlink.

In the first embodiment, the transmission stop of the eMBB transmission signal is determined using the transmission power allocated to the eMBB transmission signal, but the eMBB transmission signal is further considered in consideration of a plurality of ACKs / NACKs included in the eMBB transmission signal. You may decide to stop sending. That is, it is assumed that the terminal device 100 transmits a plurality of ACKs / NACKs collectively. In this case, when it is determined that the transmission power P _{PUSCH, c, eMBB} (i) has not reached the predetermined level, using the above equation (4), the transmission control unit 103 determines a plurality of eMBB transmission signals. It is determined whether or not all the ACKs / NACKs are NACKs. Then, when the plurality of ACKs / NACKs included in the eMBB transmission signal are all NACKs, the transmission control unit 103 eMBB transmits a DTX control signal for stopping the output of the uplink signal (that is, the eMBB transmission signal) including the eMBB data. It is output to the signal generation unit 105. Then, the transmission control unit 103 sets “Disable”, which indicates that the ACK is not stored in the buffer, in the buffering control signal, and outputs the buffering control signal to the buffer management unit 104. Furthermore, the transmission control unit 103 outputs, to the BSR insertion unit 107, a BSR reporting that ACK is not stored in the buffer, that is, a BSR in which "false" is set.

Further, the transmission control unit 103 performs the following processing when all of the plurality of ACKs / NACKs included in the eMBB transmission signal are not NACKs, that is, when at least one ACK is included in the eMBB transmission signal. That is, the transmission control unit 103 outputs, to the eMBB transmission signal generation unit 105, a DTX control signal for stopping the output of the uplink signal (that is, the eMBB transmission signal) including the eMBB data. Then, the transmission control unit 103 sets “Enable” indicating that the ACK is to be stored in the buffer in the buffering control signal, and outputs the buffering control signal to the buffer management unit 104. Furthermore, the transmission control unit 103 outputs, to the BSR insertion unit 107, a BSR that reports that the ACK is stored in the buffer, that is, a BSR in which "true" is set.

On the other hand, transmission control section 103 does not output the above DTX control signal when it is determined that transmission power P _{PUSCH, c, eMBB} (i) has reached a predetermined level, using equation (4) above. . Then, the transmission control unit 103 sets “Disable”, which indicates that the ACK is not stored in the buffer, in the buffering control signal, and outputs the buffering control signal to the buffer management unit 104. Furthermore, the transmission control unit 103 outputs, to the BSR insertion unit 107, a BSR that reports that the ACK is not stored in the buffer, that is, a BSR in which "false" is set.

The feature of the second embodiment is that, when the eMBB uplink and the URLLC uplink are set, the base station apparatus withholds the retransmission control for the data in downlink according to an advance notice that the ACK is stored in the buffer of the terminal apparatus. It is a point.

The wireless communication system according to the second embodiment is the same as the wireless communication system according to the first embodiment (FIG. 1), and thus the description thereof will be omitted. FIG. 9 is a block diagram illustrating a configuration example of the terminal device 100 according to the second embodiment. In FIG. 9, the same parts as those in FIG. 2 are denoted by the same reference numerals, and the description thereof is omitted. The terminal device 100 illustrated in FIG. 9 includes an uplink setting unit 131 and a buffering prediction (BP) generation unit 132 in place of the BSR insertion unit 107 in FIG. 2.

The uplink setting unit 131 sets an eMBB uplink for transmitting the eMBB transmission signal and a URLLC uplink for transmitting the URLLC transmission signal. The uplink setting unit 131 sets up the eMBB uplink and the URLLC uplink by, for example, upper layer signaling such as RRC (Radio Resource Control) signaling in cooperation with the base station apparatus 200.

The BP generation unit 132 generates a BP notifying that the ACK is to be stored in the buffer of the terminal device 100 when the uplink setting unit 131 sets the eMBB uplink and the URLLC uplink. That is, when both the eMBB uplink and the URLLC uplink are set, the BP generation unit 132 generates a BP in which “true” indicating that ACK is stored in the buffer of the terminal device 100 is set. When only the eMBB uplink or only the URLLC uplink is set, the BP generation unit 132 generates a BP in which “false” is set. Then, the BP generation unit 132 outputs the generated BP to the eMBB transmission signal generation unit 105 or the URLLC transmission signal generation unit 106. Thereby, for example, when RRC signaling is performed, BP is inserted into the signaling message generated by eMBB transmission signal generation unit 105 or URLLC transmission signal generation unit 106, and BP is transmitted via wireless transmission unit 100b. .

FIG. 10 is a block diagram illustrating a configuration example of a base station apparatus 200 according to a second embodiment. In FIG. 10, the same parts as those in FIG. The base station apparatus 200 shown in FIG. 10 has an uplink setting section 211 and a retransmission control section 212 instead of the BSR extraction section 203 of FIG.

The uplink setting unit 211 sets up the eMBB uplink and the URLLC uplink by, for example, upper layer signaling such as RRC signaling in cooperation with the terminal device 100. At this time, uplink setting section 211 extracts a BP from the signaling message decoded by eMBB data decoding section 201 and URLLC data decoding section 202, and outputs the extracted BP to retransmission control section 212.

The retransmission control unit 212 receives an input of the decoding (reception) result of the eMBB data from the eMBB data decoding unit 201. Retransmission control unit 212 receives an input of BP from uplink setting unit 211. The retransmission control unit 212 suspends retransmission control for the terminal device 100 based on the BP and the result of decoding (reception) of eMBB data.

Specifically, the retransmission control unit 212 performs the following processing when “true” is set to BP, that is, when it is notified that ACK is to be stored in the buffer of the terminal device 100. When the decoding result of the eMBB data is ACK, the retransmission control unit 212 outputs “new information” indicating that the data to be transmitted to the downlink is new data as DCI to the PDCCH generation unit 205, and the new data Are output to the PDSCH generation unit 207. Also, when the decoding result of the eMBB data is NACK, the retransmission control unit 212 outputs “retransmission information” indicating that the data transmitted to the downlink is retransmission data as DCI to the PDCCH generation unit 205, It instructs PDSCH generation section 207 to retransmit retransmission data.

Also, when the decoding result of the eMBB data is DTX, the retransmission control unit 212 suspends the retransmission control for the terminal device 100. That is, retransmission control section 212 outputs “pending information” indicating that retransmission control to terminal apparatus 100 is suspended as DCI to PDCCH generating section 205, and causes PDSCH generating section 207 to stop output of the PDSCH signal. To direct.

On the other hand, when “false” is set to BP, that is, when it is not notified that ACK will be stored in the buffer of the terminal device 100, the retransmission control unit 212 performs the following processing. When the decoding result of the eMBB data is ACK, the retransmission control unit 212 outputs “new information” indicating that the data to be transmitted to the downlink is new data as DCI to the PDCCH generation unit 205, and the new data Are output to the PDSCH generation unit 207. Also, when the decoding result of the eMBB data is NACK, the retransmission control unit 212 outputs “retransmission information” indicating that the data transmitted to the downlink is retransmission data as DCI to the PDCCH generation unit 205, It instructs PDSCH generation section 207 to retransmit retransmission data.

Next, a wireless communication method in the wireless communication system configured as described above will be described with reference to FIG. FIG. 11 is a sequence diagram illustrating an example of a wireless communication method according to the second embodiment.

The terminal device 100 and the base station device 200 set up the eMBB uplink and the URLLC uplink, for example, by upper layer signaling such as RRC signaling (step S141). Since both the eMBB uplink and the URLLC uplink are set, the terminal device 100 generates a BP notifying that ACK is stored in the buffer of the terminal device 100, and transmits the generated BP using a signaling message. (Step S142). The base station apparatus 200 that has received the signaling message extracts the BP from the signaling message.

The base station apparatus 200 transmits the signal of PDSCH including new data using the downlink (step S143). While transmission of URLLC data by the terminal device 100 has not occurred, the terminal device 100 transmits an eMBB transmission signal including ACK / NACK as eMBB data indicating success or failure of reception (decoding) of data in the downlink. Then, the base station apparatus 200 transmits new data or retransmission data according to ACK / NACK.

Then, when the URLLC data is generated in the terminal device 100 (step S144), the terminal device 100 allocates transmission power to the eMBB transmission signal and the URLLC transmission signal (step S145). Since the URLLC data has higher priority than the eMBB data such as ACK / NACK, the terminal device 100 preferentially allocates the transmission power to the uplink signal including the URLLC data, that is, the URLLC transmission signal. Therefore, it is assumed that the transmission power allocated to the eMBB transmission signal does not reach a predetermined level for correctly receiving (decoding) the eMBB data in the base station apparatus 200.

In this case, the terminal device 100 stops transmission of an eMBB transmission signal including ACK / NACK as eMBB data (step S146). Then, the terminal device 100 stores, in the buffer in the terminal device 100, an ACK, which is eMBB data indicating that reception of data on the downlink has succeeded among the eMBB data (step S147). Then, the terminal device 100 transmits a URLLC transmission signal on the URLLC uplink (step S148).

The base station apparatus 200 withholds retransmission control for the terminal apparatus 100 when the decoding result of the eMBB data is DTX because the BP has notified that the ACK will be stored in the buffer of the terminal apparatus 100 (DTX) (step S149, 150). Then, the base station apparatus 200 transmits, using a downlink, a PDCCH signal including, as DCI, “pending information” indicating that retransmission control for the terminal apparatus 100 is suspended (step S151).

When receiving the signal of the PDCCH including “pending information” as DCI, the terminal apparatus 100 reads ACK from the buffer according to “pending information” (step S152), and transmits an uplink signal including ACK (step S153).

When receiving the uplink signal including the ACK, the base station apparatus 200 resumes the retransmission control for the terminal apparatus 100 (step S154). In the example of FIG. 11, the base station apparatus 200 discards the PDSCH signal stored in the past in the retransmission buffer 208 according to the ACK, and transmits the PDSCH signal including new data using the downlink.

Next, the retransmission control operation in base station apparatus 200 will be described with reference to FIG. FIG. 12 is a flowchart of an example of the retransmission control operation according to the second embodiment.

The retransmission control unit 212 performs the following processing when “true” is set to BP, that is, when it is notified that ACK is stored in the buffer of the terminal device 100 (Yes at step S161). The retransmission control unit 212 outputs “new information” indicating that the data to be transmitted to the downlink is new data to the PDCCH generation unit 205 as DCI when the decoding result of the eMBB data is ACK (Yes at step S162) Outputs the new data to the PDSCH generation unit 207. As a result, a PDSCH signal including new data is generated in the PDSCH generation unit 207, and the signal of the PDSCH is transmitted as a transmission signal through the wireless transmission unit 200b (step S163). Furthermore, the PDCCH generation unit 205 generates a signal of PDCCH including “new information”, and the signal of the PDCCH is transmitted as a transmission signal through the wireless transmission unit 200 b.

Also, when the decoding result of the eMBB data is NACK (No at step S162 and step S164), the retransmission control unit 212 performs PDCCH with “retransmission information” indicating that the data transmitted to the downlink is retransmission data as DCI. It outputs to generation section 205 and instructs PDSCH generation section 207 to retransmit retransmission data. As a result, a PDSCH signal including retransmission data is generated in the PDSCH generation unit 207, and the signal of the PDSCH is transmitted as a transmission signal via the wireless transmission unit 200b (step S165). Further, the PDCCH generation unit 205 generates a signal of PDCCH including “retransmission information”, and the signal of the PDCCH is transmitted as a transmission signal through the wireless transmission unit 200 b.

In addition, when the decoding result of the eMBB data is DTX (No in step S162 and step S164), the retransmission control unit 212 suspends retransmission control on the terminal device 100 (step S166). That is, retransmission control section 212 outputs “pending information” indicating that retransmission control to terminal apparatus 100 is suspended as DCI to PDCCH generating section 205, and causes PDSCH generating section 207 to stop output of the PDSCH signal. To direct. As a result, the output of the PDSCH signal from the PDSCH generation unit 207 is stopped. Further, the PDCCH generation unit 205 generates a signal of PDCCH including “pending information”, and the signal of the PDCCH is transmitted as a transmission signal through the wireless transmission unit 200 b. The terminal device 100 that has received the signal of the PDCCH including the "pending information" reads the ACK from the buffer according to the "pending information", and transmits an uplink signal including the ACK.

On the other hand, when "false" is set to BP, that is, when it is not notified that the ACK is stored in the buffer of the terminal device 100 (No at step S161), the retransmission control unit 212 performs the following processing. The retransmission control unit 212 outputs “new information” indicating that the data to be transmitted to the downlink is new data as the DCI to the PDCCH generation unit 205 when the decoding result of the eMBB data is ACK (Yes at step S167) Outputs the new data to the PDSCH generation unit 207. As a result, a PDSCH signal including new data is generated in the PDSCH generation unit 207, and the signal of the PDSCH is transmitted as a transmission signal via the wireless transmission unit 200b (step S168). Furthermore, the PDCCH generation unit 205 generates a signal of PDCCH including “new information”, and the signal of the PDCCH is transmitted as a transmission signal through the wireless transmission unit 200 b.

In addition, when the decoding result of the eMBB data is NACK (No at step S167), retransmission control section 212 sets “retransmission information” indicating that the data to be transmitted to the downlink is retransmission data as DCI to PDCCH generation section 205. And the PDSCH generation unit 207 to retransmit retransmission data. As a result, a PDSCH signal including retransmission data is generated in the PDSCH generation unit 207, and the signal of the PDSCH is transmitted as a transmission signal via the wireless transmission unit 200b (step S169). Further, the PDCCH generation unit 205 generates a signal of PDCCH including “retransmission information”, and the signal of the PDCCH is transmitted as a transmission signal through the wireless transmission unit 200 b.

As described above, according to the present embodiment, when the eMBB uplink and the URLLC uplink are set up, the terminal transmits a BP notifying that ACK is stored in the buffer of the terminal, and the base The station apparatus suspends retransmission control based on the BP and the decoding result of eMBB data. Therefore, the retransmission control in the base station apparatus can be put on hold simply by transmitting the BP once by the terminal apparatus, and the terminal apparatus performs a BSR every time an ACK is stored in the buffer of the terminal apparatus as in the first embodiment. It will not be sent. As a result, the processing load associated with BSR transmission can be reduced.

100 terminal device 101 path loss measurement unit 102 transmission power allocation unit 103 transmission control unit 104 buffer management unit 105 eMBB transmission signal generation unit 106 URLLC transmission signal generation unit 107 BSR insertion unit 108 PDCCH decoding unit 109 DCI determination unit 110 PDSCH decoding unit 111 ACK / NACK generation unit 121 buffer 122 selection unit 123 buffer control unit 131, 211 uplink control unit 132 BP generation unit 200 base station apparatus 201 eMBB data decoding unit 202 URLLC data decoding unit 203 BSR extraction unit 204, 212 retransmission control unit 205 PDCCH Generation unit 206 Power information management unit 207 PDSCH generation unit 208 Retransmission buffer

Claims

An assignment unit that assigns transmission power to an uplink signal including first data and an uplink signal including second data having a higher priority than the first data;
A transmission control unit that stops transmission of an uplink signal including the first data when transmission power allocated to the uplink signal including the first data does not reach a predetermined level;
A buffer management unit that stores, in a buffer, an ACK, which is the first data indicating that data reception on the downlink has succeeded, when the transmission is stopped;
And a transmitter configured to transmit, using an uplink signal including the second data, a buffer status report that reports that the ACK has been stored in the buffer and suspends retransmission control for the data. Terminal equipment.
The base station further includes a receiving unit for receiving suspension information indicating that the retransmission control is suspended from the base station apparatus which suspends retransmission control for the data according to the buffer status report;
The buffer management unit
When the transmission power allocated to the uplink signal including the first data reaches a predetermined level and the hold information is received, the ACK is read from the buffer;
The transmission unit is
The terminal apparatus according to claim 1, wherein the base station apparatus is caused to resume the retransmission control by transmitting an uplink signal including an ACK read from the buffer.
A receiving unit for receiving a buffer status report for reporting that an ACK, which is data indicating that data has been successfully received on the downlink, has been stored in the buffer of the terminal apparatus and holding retransmission control for the data;
And a retransmission control unit which suspends retransmission control for the data according to the received buffer status report.
A first uplink for transmitting an uplink signal including first data and a second uplink for transmitting an uplink signal including second data having higher priority than the first data are set The uplink setting unit to
An assignment unit for assigning transmission power to an uplink signal including the first data and an uplink signal including the second data;
A transmission control unit that stops transmission of an uplink signal including the first data when transmission power allocated to the uplink signal including the first data does not reach a predetermined level;
A buffer management unit that stores, in a buffer, an ACK, which is the first data indicating that data reception on the downlink has succeeded, when the transmission is stopped;
Buffering that suspends retransmission control related to the data by giving notice that the ACK is stored in the buffer when the first uplink and the second uplink are set by the uplink setting unit And a transmitting unit for transmitting a notice.
A first uplink for transmitting an uplink signal including first data, and a second uplink for transmitting an uplink signal including second data having higher priority than the first data; A receiving unit for receiving a buffering notice for notifying that the first data ACK indicating that reception of data on the downlink has succeeded is stored in the buffer of the terminal device;
A retransmission control unit which suspends retransmission control for the data according to the buffering notice and the decoding result of the first data.
A wireless communication system having a terminal device and a base station device,
The terminal device is
An assignment unit that assigns transmission power to an uplink signal including first data and an uplink signal including second data having a higher priority than the first data;
A transmission control unit that stops transmission of an uplink signal including the first data when transmission power allocated to the uplink signal including the first data does not reach a predetermined level;
A buffer management unit that stores, in a buffer, an ACK, which is the first data indicating that data reception on the downlink has succeeded, when the transmission is stopped;
And a transmitter configured to transmit, using an uplink signal including the second data, a buffer status report that reports that the ACK has been stored in the buffer and suspends retransmission control for the data;
The base station apparatus
A receiving unit that receives the buffer status report transmitted from the transmitting unit;
And a retransmission control unit which suspends retransmission control for the data according to the received buffer status report.
A wireless communication method in a wireless communication system including a terminal device and a base station device,
Assigning transmission power to an uplink signal including first data and an uplink signal including second data having a higher priority than the first data;
When the transmission power allocated to the upstream signal including the first data does not reach a predetermined level, the transmission of the upstream signal including the first data is stopped.
Storing, in the buffer, an ACK, which is the first data indicating that the data has been successfully received on the downlink, when the transmission is stopped;
Transmitting, using an uplink signal including the second data, a buffer status report that reports that the ACK has been stored in the buffer and suspends retransmission control for the data;
The base station apparatus
Receive a buffer status report sent from the terminal;
A wireless communication method comprising: a process of suspending retransmission control for the data according to a received buffer status report.