JP2020174381A - Terminal and communication method - Google Patents

Abstract

To provide a method and a terminal capable of properly setting the transmission power distribution when a TTI length is different.SOLUTION: A terminal 200 includes: a transmission power determination unit 211 that is configured so as to, when transmitting a second uplink signal with a second TTI shorter than a first TTI in a first TTI (Transmission Time Interval) for transmitting the first uplink signal, determine the transmission power of the first uplink signal and the second uplink signal so that the transmission power is preferentially allocated to the second uplink signal; and a transmitting unit 212 that transmits the first uplink signal and the second uplink signal with the determined transmission power.SELECTED DRAWING: Figure 4

Description

The present disclosure relates to terminals and communication methods.

In recent years, it has been considered to realize an application that requires a reduction in delay time (delay critical). Examples of applications that require reduced delay times include autonomous driving of cars, ultra-reality applications in smart glasses, and communication between devices.

In 3GPP, latency reduction that reduces packet delay is being studied in order to realize these applications (see Non-Patent Document 1). In Latency reduction, it is considered to reduce the TTI (Transmission Time Interval) length, which is a unit of time for transmitting and receiving data, to a length between 0.5 msec and 1 OFDM symbol. The conventional TTI length is 1 msec, which is equal to a unit called a subframe. One subframe consists of two slots (one slot is 0.5 msec). In the case of normal CP (Cyclic Prefix), 1slot is composed of 7 OFDM (Orthogonal Frequency Division Multiplexing) symbols, and in the case of extended CP, it is composed of 6 OFDM symbols. For example, if the shortened TTI length is 0.5 msec (= 1 slot), 2 TTIs are arranged per 1 msec. Also, when 1 slot is divided into a TTI with 4OFDM symbols and a TTI with 3OFDM symbols, 4TTIs are placed per 1msec. If the TTI length is 2 symbols, 7 TTIs are placed per 1 msec.

By shortening the TTI length, the delay of CQI reporting can be shortened and the frequency of CQI reporting can be increased, which has the advantage of reducing the discrepancy between the CQI reporting and the actual line quality.

RP-150465, "New SI proposal: Study on Latency reduction techniques for LTE," Ericsson, Huawei, March 2015 3GPP TR 36.211 V13.0.0, “Physical channels and modulation (Release 13),” December 2015 R1-164923, "Simultaneous Transmission of UL Signals for Shortened TTI Operation," Nokia, Alcatel-Lucent Shanghai Bell, May 2016

For example, shortening the TTI length can be applied not only to systems that extend LTE (Long Term Evolution), but also to systems that are realized in a new frame format called New RAT (Radio Access Technology). In New RAT, the number of symbols per 1msec may be different from the above LTE. When operating a TTI with a shortened TTI length (hereinafter referred to as sTTI: short TTI), it is conceivable to support a plurality of TTI lengths at the same time (see, for example, Non-Patent Document 3). By supporting multiple TTI lengths, the TTI length can be selected and used properly according to the requirements of different applications. For example, long TTIs can be used for delay-tolerant packets and sTTIs can be used for delay-sensitive packets.

However, if the maximum transmission power that can be used by the terminal (sometimes called the UE) is not sufficient, there is a problem that the transmission power becomes insufficient when each packet using multiple TTIs with different TTI lengths is transmitted at the same time. .. Therefore, it is necessary to consider the distribution of transmission power when the TTI length is different.

One aspect of the present disclosure is to provide a terminal and a communication method capable of appropriately setting the distribution of transmission power when the TTI length is different.

When the terminal according to one aspect of the present disclosure transmits the second uplink signal at the second TTI shorter than the first TTI in the first TTI (Transmission Time Interval) for transmitting the first uplink signal, the terminal uses the second uplink signal. A transmission power determination unit that determines the transmission power of the first uplink signal and the second uplink signal, respectively, so as to preferentially allocate the transmission power, and the first uplink signal and the second uplink with the determined transmission power. A configuration is adopted in which a transmission unit for transmitting an uplink signal is provided.

The communication method according to one aspect of the present disclosure is the second uplink signal when the second uplink signal is transmitted at the second TTI shorter than the first TTI in the first TTI (Transmission Time Interval) for transmitting the first uplink signal. The transmission powers of the first uplink signal and the second uplink signal are determined, respectively, so as to preferentially allocate the transmission power to, and the first uplink signal and the second uplink signal are transmitted by the determined transmission power. To do.

It should be noted that these comprehensive or specific embodiments may be realized in a system, device, method, integrated circuit, computer program, or recording medium, and the system, device, method, integrated circuit, computer program, and recording medium. It may be realized by any combination of.

According to one aspect of the present disclosure, the distribution of transmitted power when the TTI length is different can be appropriately set.

Further advantages and effects in one aspect of the present disclosure will be apparent from the specification and drawings. Such advantages and / or effects are provided by some embodiments and features described in the specification and drawings, respectively, but not all need to be provided in order to obtain one or more identical features. There is no.

Diagram showing an example of power distribution between TTIs with different TTI lengths Block diagram showing the main part configuration of the terminal according to the first embodiment Block diagram showing the configuration of the base station according to the first embodiment Block diagram showing the configuration of the terminal according to the first embodiment The figure which shows an example of the transmission power control which concerns on operation example 1-1 of Embodiment 1. The figure which shows another example of the transmission power control which concerns on operation example 1-1 of Embodiment 1. The figure which shows an example of the transmission power control which concerns on operation example 1-2 of Embodiment 1. The figure which shows the other transmission power control of Embodiment 1. The figure which shows the setting example of the Transient period which concerns on operation example 2-1 of Embodiment 2. The figure which shows the setting example of the Transient period which concerns on operation example 2-1 of Embodiment 2. The figure which shows the setting example of the Transient period which concerns on operation example 2-1 of Embodiment 2. The figure which shows the setting example of the Transient period which concerns on operation example 2-1 of Embodiment 2. The figure which shows the other setting example of the Transient period which concerns on operation example 2-1 of Embodiment 2. The figure which shows the setting example of the Transient period which concerns on operation example 2-2 of Embodiment 2.

[Background to one aspect of this disclosure]
Hereinafter, the circumstances leading to one aspect of the present disclosure will be described.

[Dual connectivity operation]
Dual connectivity allows terminals to transmit UL (Uplink) signals simultaneously in multiple cells. Each cell belongs to MCG (Master Cell Group) or SCG (Secondary Cell Group), and can prioritize and allocate transmission power to UL transmission of MCG and UL transmission of SCG. Further, each CG (Cell Group) includes one PCell (Primary Cell) and one or a plurality of SCells (Secondary Cells). In Dual connectivity, RACH (Random Access Channel) transmitted to the Pcell of MCG has the highest priority, and then the priority is assigned to each channel as follows.
HARQ-ACK = SR>CSI> PUSCH without UCI

When the same channel is transmitted between the MCG and the SCG, the UL transmission of the MCG has priority over the UL transmission of the SCG.

[Premise]
In Dual connectivity, the minimum guaranteed power is assigned to each CG as the power distribution in UL transmission. When the terminal uses the transmission power equal to or higher than the minimum guaranteed power, the terminal can use the surplus transmission power (surplus power. Remaining power) according to the priority. Another method of power distribution applied when the MCG and SCG are not synchronized is that the transmission power of the signal that started to be transmitted earlier is not changed.

Regarding the power distribution between each TTI when supporting multiple TTI lengths at the same time, it is conceivable to allocate the minimum guaranteed power in the same way as Dual connectivity, that is, by regarding each TTI as a Cell group (for example, in the figure). See 1). For example, if each TTI requires more than the minimum guaranteed power transmission power, either a method of allocating the remaining power according to priority, or using the remaining power for the TTI signal that started transmitting earlier. The method of being able to do it is conceivable.

There are the following methods as a power distribution method when a plurality of TTIs having different TTI lengths coexist. In the following, TTIs having different TTI lengths will be referred to as long TTI (long TTI or simply TTI) and short TTI (sTTI), respectively.

Method 1: First, the priority is determined by the type of channel, and then, in the case of the same channel, the priority is determined by the length of TTI.
Method 2: First, the TTI length determines the priority, and then the channel type determines the priority.
Method 3: The required power can be used for the signal that started transmission earlier.

As the priority according to the type of channel in Method 1 and Method 2, the priority of RACH> HARQ-ACK = SR> CSI> PUSCH without UCI can be considered. RACH has a high priority because it is information necessary for communication connection or synchronous acquisition. With HARQ-ACK, if reception is mistaken, useless HARQ retransmission of DL (Downlink) data may occur, or retransmission may occur in the upper layer without performing HARQ retransmission even though retransmission is required. Because it has sex, it has a high priority. SR (Scheduling Request) has a high priority because it is information necessary for starting UL communication. On the other hand, PUSCH (Physical Uplink Shared Channel) without UCI (Uplink Control Information) has a priority because it does not have a large impact on the system because UL data can be retransmitted when the reception quality of UL data deteriorates. Low. However, if the UL data has a higher priority than the DL data, the PUSCH priority may be higher than the HAQR-ACK.

As the priority according to the length of the TTI, it is preferable to give priority to the sTTI when the packet whose delay time should be shortened is transmitted by the sTTI and the packet whose delay is allowed is transmitted by the TTI. In addition, although sTTI is used, it is preferable to give priority to TTI when the line quality condition deteriorates and the system is switched to TTI. The priority according to the length of the TTI may be predetermined by the system, and the base station (sometimes called eNB) notifies the terminal of information indicating which TTI length is prioritized. May be good.

Further, in Method 1, after the priority is determined by the type of channel, in the case of the same channel, which TTI length of TTI or sTTI is prioritized may be determined for each channel.

[Task]
If multiple TTI UL signals with different TTI lengths are transmitted at the same time, the sTTI UL signal may be assigned and the sTTI UL signal transmission may start after the long TTI UL signal transmission starts. is there. In such a case, even if the UL signal of sTTI has a higher priority than the UL signal of sTTI, power is already allocated to the UL signal of long TTI, so if the surplus power is small, UL of sTTI There is a problem that the power allocated to the signal is insufficient.

Also, like SR, when the terminal spontaneously transmits a signal with sTTI instead of being assigned from the base station, if power is already allocated to the UL signal of the long TTI, it is assigned to the UL signal of sTTI. There is a problem of running out of power. In particular, delaying SR affects the transmission delay of TCP ACK, and there is a problem that user throughput is reduced. In order to give priority to sTTI, it is possible to increase the Guaranteed power of sTTI, but there is a problem that the power allocated to TTI is always small.

In addition, in the method in which the UL signal that started to be transmitted first uses surplus power without deciding the priority according to the TTI length, the long TTI uses surplus power more often than the sTTI. There will be a bias.

Therefore, one aspect of the present disclosure is to provide appropriate power distribution when transmitting UL signals having different TTI lengths.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[Outline of communication system]
The communication system according to each embodiment of the present disclosure includes a base station 100 and a terminal 200.

FIG. 2 is a block diagram showing a configuration of a main part of the terminal 200 according to the embodiment of the present disclosure. In the terminal 200 shown in FIG. 2, the transmission power determination unit 211 has a shorter TTI length than the first TTI while transmitting an uplink signal in the first section that refers to the first reference signal within the first TTI (Transmission Time Interval). When the uplink signal of the second TTI is generated, in the first section, the transmission power of the first reference signal and the uplink signal of the first TTI is kept constant, the transmission power is not allocated to the uplink signal of the second TTI, and the first TTI is within the first TTI. In the second section following the first section and referencing the second reference signal, the first TTI and the second TTI so as to reduce the transmission power of the uplink signal of the first TTI and allocate the transmission power to the uplink signal of the second TTI. The transmission power of the uplink signal is determined respectively. The transmission unit 212 transmits the uplink signals of the first TTI and the second TTI with the determined transmission power.

(Embodiment 1)
[Base station configuration]
FIG. 3 is a block diagram showing the configuration of the base station 100 according to the present embodiment. In FIG. 3, the base station 100 includes a DCI generation unit 101, an error correction coding unit 102, a modulation unit 103, a signal allocation unit 104, a transmission unit 105, a reception unit 106, and a signal separation unit 107. It has an ACK / NACK receiving unit 108, a demodulating unit 109, and an error correction decoding unit 110.

The DCI generation unit 101 determines whether to transmit the transmission data signal (DL data signal) by sTTI, TTI, or both sTTI and TTI. Further, the DCI generation unit 101 determines whether the UL data signal is received by sTTI, TTI, or both sTTI and TTI based on the power information of the terminal 200 received from the error correction decoding unit 110. decide. Then, the DCI generation unit 101 performs DL data based on the content (ACK or NACK) of the ACK / NACK signal (that is, the ACK / NACK signal with respect to the DL data signal (PDSCH)) input from the ACK / NACK receiving unit 108. It is determined whether or not signal retransmission is necessary, and DCI for sTTI or DCI for TTI is generated according to the determination result. The DCI generation unit 101 outputs a control signal (resource allocation information, etc.) related to DL to the signal allocation unit 104, and outputs a control signal (resource allocation information, etc.) related to UL to the signal separation unit 107. Further, the DCI generation unit 101 outputs the generated DCI to the signal allocation unit 104 in order to transmit it to the terminal 200.

The error correction coding unit 102 error-corrects and encodes the transmission data signal (DL data signal) and the signaling of the upper layer (not shown), and outputs the coded signal to the modulation unit 103.

The modulation unit 103 performs modulation processing on the signal received from the error correction coding unit 102, and outputs the modulated signal to the signal allocation unit 104.

The signal allocation unit 104 allocates the signal received from the modulation unit 103 and the DCI received from the DCI generation unit 101 to a predetermined downlink resource based on the DL control signal input from the DCI generation unit 101. In this way, the transmission signal is formed. The formed transmission signal is output to the transmission unit 105.

The transmission unit 105 performs wireless transmission processing such as up-conversion on the transmission signal input from the signal allocation unit 104, and transmits the transmission signal to the terminal 200 via the antenna.

The reception unit 106 receives the signal transmitted from the terminal 200 via the antenna, performs wireless reception processing such as down-conversion on the received signal, and outputs the received signal to the signal separation unit 107.

The signal separation unit 107 specifies the reception frequency and time timing of the UL data signal and the ACK / NACK signal based on the UL control signal input from the DCI generation unit 101. Then, the signal separation unit 107 separates the UL data signal from the reception signal and outputs it to the demodulation unit 109, separates the ACK / NACK signal from the reception signal, and outputs it to the ACK / NACK reception unit 108.

The ACK / NACK receiving unit 108 outputs the content (ACK or NACK) of the ACK / NACK signal with respect to the DL data signal input from the signal separating unit 107 to the DCI generation unit 101.

The demodulation unit 109 performs demodulation processing on the signal input from the signal separation unit 107, and outputs the obtained signal to the error correction decoding unit 110.

The error correction decoding unit 110 decodes the signal input from the demodulation unit 109 to obtain the received data signal (UL data signal) from the terminal 200. Further, the error correction / decoding unit 110 outputs the power information of the terminal 200 notified in the upper layer among the received data signals to the DCI generation unit 101.

[Terminal configuration]
FIG. 4 is a block diagram showing the configuration of the terminal 200 according to the present embodiment. In FIG. 4, the terminal 200 includes a receiving unit 201, a signal separating unit 202, a demodulation unit 203, an error correction decoding unit 204, an error determination unit 205, an ACK / NACK generating unit 206, and a DCI receiving unit 207. It has an error correction coding unit 208, a modulation unit 209, a signal allocation unit 210, a transmission power determination unit 211, and a transmission unit 212.

The receiving unit 201 receives the received signal through the antenna, performs reception processing such as down-conversion on the received signal, and then outputs the received signal to the signal separation unit 202.

The signal separation unit 202 separates the signals arranged in the resources to which DCI may be assigned and outputs them to the DCI reception unit 207. Further, the signal separation unit 202 separates the DL data signal from the reception signal based on the control signal (resource allocation information) regarding the DL input from the DCI reception unit 207, and outputs the DL data signal to the demodulation unit 203.

The demodulation unit 203 demodulates the signal received from the signal separation unit 202 and outputs the demodulated signal to the error correction decoding unit 204.

The error correction decoding unit 204 decodes the demodulation signal received from the demodulation unit 203 and outputs the obtained received data signal. Further, the error correction / decoding unit 204 outputs the received data signal to the error determination unit 205.

The error determination unit 205 detects an error by CRC (Cyclic Redundancy Check) of the received data signal, and outputs the detection result to the ACK / NACK generation unit 206.

The ACK / NACK generation unit 206 generates ACK if there is no error, generates NACK if there is an error, and generates ACK / generated based on the detection result of the received data signal input from the error determination unit 205. The NACK signal is output to the signal allocation unit 210.

The DCI receiving unit 207 outputs a control signal (resource allocation information, etc.) related to DL shown in the DCI (DCI for TTI or DCI for sTTI) received from the signal separation unit 202 to the signal separation unit 202, and outputs a control signal (resource) related to UL. (Allocation information, etc.) is output to the signal allocation unit 210.

The error correction coding unit 208 error-corrects and encodes the transmission data signal (UL data signal), and outputs the encoded data signal to the modulation unit 209.

The modulation unit 209 modulates the data signal received from the error correction coding unit 208, and outputs the modulated data signal to the signal allocation unit 210.

The signal allocation unit 210 allocates the data signal input from the modulation unit 209 to the resource based on the control signal (resource allocation information) related to UL received from the DCI reception unit 207, and outputs the data signal to the transmission unit 212. Further, the signal allocation unit 210 allocates the ACK / NACK signal input from the ACK / NACK generation unit 206 to the ACK / NACK resource, or multiplexes the UL data signal and outputs the signal to the transmission unit 212.

The transmission power determination unit 211 determines the transmission power according to the priority with respect to the transmission signal and the ACK / NACK signal input from the signal allocation unit 210. For example, when the transmission power determination unit 211 allocates the transmission power to the UL signal of the long TTI and then the UL signal having a high priority of sTTI is generated, the transmission power of the UL signal of the long TTI is being transmitted. Change with. The transmission power determination unit 211 outputs power information indicating the determined transmission power to the transmission unit 212. The transmission power determination unit 211 may notify the power 0 when there is no power to be allocated to the UL signal.

The amount of resources allocated by the signal allocation unit 210 is reduced for the signal instructed by the transmission power determination unit 211 to reduce the transmission power.

The transmission unit 212 sets the transmission power based on the transmission power information input from the transmission power determination unit 211, and with respect to the signal input from the signal allocation unit 210 and the power information input from the transmission power determination unit 211. Transmission processing such as up-conversion is performed, and transmission is performed via an antenna. As a result, the UL signals of the long TTI and sTTI are transmitted with the transmission power determined by the transmission power determination unit 211.

[Operation of base station 100 and terminal 200]
The operations of the base station 100 and the terminal 200 having the above configuration will be described in detail.

Hereinafter, operation examples 1-1 and operation examples 1-2 according to the present embodiment will be described.

<Operation example 1-1>
In operation example 1-1, based on the LTE system, a long TTI is set to 1 msec, which is the subframe length of LTE, and a normal LTE operation is assumed for a long TTI.

Further, in the operation example 1-1, the priority of the UL channel is HARQ-ACK = SR> CSI> PUSCH without UCI regardless of the TTI length.

Further, here, while the terminal 200 is transmitting a UL signal of a long TTI (for example, PUSCH / PUCCH), a UL signal of sTTI (for example, SR) having a higher priority than the UL signal of the long TTI is generated. An example will be described.

When SR of sTTI occurs while transmitting a UL signal of long TTI, the terminal 200 confirms the transmission power (surplus power) that can be allocated to SR. Then, when the terminal 200 determines that the transmission power required for the transmission of the SR can be allocated, the terminal 200 transmits the SR at an arbitrary timing.

On the other hand, when the transmission power required for SR transmission is not allocated, the terminal 200 waits until the timing at which the transmission power of the UL signal of the long TTI can be changed, and transmits the SR after that timing.

First, a case where the terminal 200 transmits PUCCH using a long TTI will be described.

In PUCCH, the PRB (Physical Resource Block) to be transmitted changes for each slot, and the orthogonal code is also applied for each slot, and the transmission power of PUCCH is changed for each slot. Therefore, even if the transmission power of PUCCH is changed for each slot, the orthogonality of the signal can be maintained. In other words, the timing at which the transmission power of the PUCCH of a long TTI can be changed is the timing at the boundary of the slots.

Therefore, when sufficient transmission power is not allocated to the SR of the sTTI, the terminal 200 waits until the next slot where the transmission power of the PUCCH of the long TTI can be changed, and the sTTI arranged in the next slot Send SR.

FIG. 5 shows an example of transmission power control (power distribution) of the long TTI and sTTI according to the operation example 1-1. In FIG. 5, four sTTIs (sTTI # 0 to sTTI # 3) are arranged per one subframe (1 msec). Further, in FIG. 5, SR of sTTI occurs in the section of sTTI # 0.

Further, in FIG. 5, in sTTI # 0 (the section in slot # 0), even if the minimum guaranteed power of sTTI and the surplus power not used in the PUCCH of the long TTI are combined, the transmission required for SR transmission is performed. Power cannot be allocated.

In this case, the terminal 200 waits for SR transmission until the slot division where the transmission power of the PUCCH of the long TTI can be changed, and transmits SR in the next slot # 1. Specifically, as shown in FIG. 5, the terminal 200 converts the SR of sTTI generated in the section of slot # 0 (sTTI # 0) in the long TTI into the section of slot # 0 (that is, sTTI # 0, sTTI # 1) waits without sending. Then, the terminal 200 transmits SR at sTTI # 2 in the section of slot # 1.

At this time, the terminal 200 keeps the transmission power of the PUCCH of the long TTI constant without changing it in the slot # 0 where the SR of the sTTI is generated.

Further, the terminal 200 reduces the transmission power of the long TTI PUCCH in slot # 1 so that the transmission power required for the transmission of the SR of the sTTI is secured. That is, the terminal 200 determines the transmission power of the long TTI and the UL signal of the sTTI, respectively, so as to reduce the transmission power of the PUCCH of the long TTI and allocate the transmission power to the SR of the sTTI.

The terminal 200 keeps the transmission power of the long TTI PUCCH at the same transmission power as that of sTTI # 2 even in the section of sTTI # 3 after the SR transmission of sTTI # 2 is completed in slot # 1. That is, PUCCH is transmitted in slot # 1 with a constant transmission power.

By doing so, the transmission power of PUCCH is changed on a slot-by-slot basis due to the allocation of power to SR of sTTI. As a result, the terminal 200 can allocate sufficient transmission power to the SR of the sTTI having a high priority while ensuring the reception quality characteristic for the PUCCH of the long TTI. That is, the terminal 200 can simultaneously transmit the long TTI PUCCH and the sTTI SR in sTTI # 2 (slot # 1) with an appropriate transmission power. In other words, the terminal 200 can interrupt the SR of the sTTI in the middle of transmitting the PUCCH of the long TTI and transmit it. Therefore, the terminal 200 can suppress the transmission delay of the SR of sTTI.

Next, a case where the terminal 200 transmits PUSCH using a long TTI will be described.

When the modulation method of PUSCH is a modulation method that does not use amplitude (BPSK / QPSK, etc.), even if the transmission power of PUSCH is changed during transmission, the demodulation of the PUSCH at the base station 100 is not affected.

Therefore, when the SR of the sTTI occurs during the transmission of the PUSCH using the long TTI, the terminal 200 transmits the SR with the transmission power required for the transmission of the SR without waiting for the transmission of the SR. At this time, the terminal 200 reduces the transmission power of the PUSCH of the long TTI in the transmission section of the SR so that the transmission power required for the transmission of the SR is secured. As a result, the terminal 200 can transmit the SR of the sTTI with an appropriate transmission power without delay without affecting the reception quality characteristics of the PUSCH of the long TTI.

On the other hand, when the PUSCH modulation method is a multi-level modulation method (16QAM, 64QAM, 256QAM) that uses amplitude, if the PUSCH transmission power is changed during transmission, the base station 100 will use a reference signal (DMRS: Demodulation Reference). There is a power difference between Signal) and the received data, which causes a problem that the received data cannot be demodulated correctly.

Therefore, the following two methods can be considered as the transmission power control (power distribution) method when the modulation method for PUSCH of long TTI is the multi-level modulation method (16QAM, 64QAM, 256QAM) using amplitude.

The first method is that if the UL signal of the sTTI and the UL signal of the long TTI can be transmitted at the same time, for the long TTI, the base station 100 without sharing the reference signal between the slots. In this method, the demodulation process is performed by closing the slot (independently).

In this way, the transmission power of the UL signal of the long TTI can be changed between slots. That is, as in the case of PUCCH, when the transmission power required for SR transmission is not allocated in a certain slot (for example, slot # 0 in FIG. 5), the terminal 200 sets the SR of sTTI to the next slot (for example, slot # 0). In FIG. 5, the SR is transmitted by waiting until the slot # 1).

That is, in FIG. 5, when the UL signal of sTTI is generated while the terminal 200 (transmission power determination unit 211) is transmitting the UL signal in slot # 0 which is a section that refers to a certain reference signal in a long TTI, In slot # 0, the transmission power of the reference signal referenced in slot # 0 and the UL signal of the long TTI is kept constant, and the transmission power is not allocated to the UL signal of sTTI. Then, the terminal 200 reduces the transmission power of the UL signal of the long TTI in slot # 1, which is a section that follows slot # 0 in the long TTI and refers to a different reference signal, and transmits power to the UL signal of the sTTI. Determine the transmission power value of the UL signal of the long TTI and sTTI so as to allocate.

In the slot (slot # 1 in FIG. 5) in which the transmission power of the long TTI to the PUSCH is reduced and the sTTI SR is transmitted, the terminal 200 has a long TTI even in the section after the sTTI SR transmission is completed. Keep the transmission power of PUSCH constant. That is, the PUSCH is transmitted in slot # 1 with a reduced constant transmission power. By doing so, it is possible to avoid a power difference between the reference signal referenced in slot # 1 and the received data, and the base station 100 can correctly demodulate the received data.

In this way, by not sharing the reference signal between slots for a long TTI, the terminal 200 can switch the transmission power for the UL signal of the long TTI in slot units, and the UL signal of the sTTI can be used. It can be interrupted. Further, by arranging the reference signal so that the base station 100 performs demodulation processing independently for each slot, it is possible to reduce the influence on the demodulation processing in the long TTI even if there is an interrupt of sTTI.

However, if there is no possibility that the UL signal of sTTI and the UL signal of long TTI are transmitted at the same time, the transmission power is constant between the slots and the reference signal is shared for the long TTI. In this way, if there is no possibility that the UL signal of the sTTI and the UL signal of the long TTI are transmitted at the same time, the reference signals of both slots can be used for the demodulation processing at the base station 100.

The second method is to puncture a part of the data part of PUSCH. Puncturing a part of PUSCH means that it is a part of RE (Resource element) assigned to PUSCH and does not send PUSCH.

For example, the terminal 200 determines the number of REs used to transmit the PUSCH per symbol, depending on the amount of PUSCH power that must be reduced to transmit the SR of the sTTI. However, when PUSCH is transmitted by a single carrier, there is a problem that PAPR (Peak to average power ratio) increases when some signals are reduced on the frequency axis. Therefore, the terminal 200 needs to determine the number of REs used for PUSCH transmission in consideration of the increase in PAPR due to the reduction of signals.

Further, as one method of puncturing, the terminal 200 realizes puncturing by puncturing the signal on the time axis before DFT (Discrete Fourier Transform) at the time of signal generation and reducing the frequency resource for mapping the signal after DFT. You may.

Further, when the PUSCH generates a waveform by single carrier transmission and transmits the divided signal, the terminal 200 may determine the RE to be punctured from one end of the divided signal. By doing so, since the number of divisions of PUSCH does not change, the increase in PAPR can be suppressed.

Further, as shown in FIG. 6, the terminal 200 may arrange the SR of the sTTI on a symbol that does not overlap with the DMRS of the long TTI. In FIG. 6, in terminal 200, in sTTI # 2 composed of 4 symbols, the SR of sTTI is arranged in 3 symbols (1st to 3rd symbols), and the DMRS of PUSCH of a long TTI is arranged in the 4th position. SR is not placed on the symbol of. In this way, the terminal 200 can transmit the DMRS after the transmission of the sTTI is completed without puncturing the DMRS. Therefore, the base station 100 can correctly demodulate the PUSCH arranged behind the slot (for example, the section corresponding to sTTI # 3 in FIG. 6) by using the DMRS arranged in the center of the slot.

In Operation Example 1-1, a power control method suitable for each channel is shown. However, if a plurality of methods are switched for each channel as a system, there is a problem that the processing becomes complicated. Therefore, the power control method may be unified among the channels, and the power control for a plurality of channels may be performed by one method. For example, as a power control method commonly used for a plurality of channels, the terminal 200 may use a method of changing the transmission power of a long TTI in slot units as described above.

In addition, the SR of sTTI may have a limited number of sTTIs that can be transmitted. This is because if the SR area is secured by all sTTIs, the resources that cannot be used for other UL channels will increase, and if there is no actual transmission of SR, the resources will not be used and resource utilization efficiency will deteriorate. is there. Therefore, if the sTTI capable of transmitting the SR is defined, the terminal 200 waits for the transmission of the SR until the sTTI capable of transmitting the SR can secure the transmission power required for transmitting the SR after the SR occurs. SR may be sent. For example, in FIG. 5, if sTTI # 2 is an sTTI that cannot transmit SR and sTTI # 3 is an sTTI that can transmit SR, the terminal 200 can change the transmission power of the UL signal of a long TTI in slot # 1. In the section from sTTI # 2 to sTTI # 3 corresponding to, the transmission power of the UL signal of the long TTI is reduced, SR is not transmitted in sTTI # 2, SR is transmitted in sTTI # 3, and the UL signal of the long TTI is transmitted. Send at the same time.

Further, the terminal 200 may transmit the surplus transmission power information (PHR: Power Head Room) to the base station 100. At this time, the terminal 200 may create PHR separately for the long TTI and the sTTI. At this time, a method in which the PHR of the long TTI is transmitted in the long TTI and the PHR of the sTTI is transmitted in the sTTI, and a method in which both PHRs are reported together in either the long TTI or the sTTI can be considered. Eh. Further, when creating a PHR in the terminal 200, it is necessary to refer to the amount of resources allocated to UL data. In the case of sTTI, UL data is not transmitted by all sTTIs, and the amount of resources may differ for each sTTI. Therefore, the terminal 200 may predetermine which sTTI number to refer to when creating the PHR. Further, the terminal 200 may refer to the sTTI to which the maximum amount of resources is allocated in the subframe when the PHR is created.

Further, in the conventional system such as LTE and LTE-Advanced, the transmission power control of the closed loop is performed by using the bit in DCI format 3 / 3A or UL grant. The terminal 200 can apply the same transmission power control as the conventional system to the UL signal of TTI. On the other hand, for the UL signal of sTTI, it is possible to include the power control information in only some UL grants without including the power control information in all UL grants. It is also possible to transmit DCI format 3 / 3A separately for sTTI, share it with TTI and sTTI, or do not apply power control in DCI format 3 / 3A to sTTI.

<Operation example 1-2>
In operation example 1-2, based on the LTE system, a long TTI is set to 1 msec, which is the subframe length of LTE, and a normal LTE operation is assumed for a long TTI. Further, in operation example 1-2, the sTTI length is set to 2 symbols, and 7 sTTI is arranged per 1 subframe.

In the operation example 1-2, similarly to the operation example 1-1, while the terminal 200 is transmitting the UL signal of the long TTI (for example, PUSCH / PUCCH), the sTTI having a higher priority than the UL signal of the long TTI An example in which a UL signal (for example, SR) is generated will be described.

When SR of sTTI occurs while transmitting a UL signal of long TTI, the terminal 200 confirms the transmission power (surplus power) that can be allocated to SR. Then, when the terminal 200 determines that the transmission power required for SR transmission can be allocated in one sTTI, it transmits SR at an arbitrary timing.

On the other hand, when the transmission power required for SR transmission is not allocated in one sTTI, the terminal 200 transmits the SR a plurality of times in a plurality of sTTIs using the minimum guaranteed power and surplus power of the sTTI. The number of SR transmissions (sTTI number) is the number of times the total value of the SR transmission power satisfies the desired SR transmission power. That is, the terminal 200 uses a plurality of sTTIs to perform repetition transmission of SR.

FIG. 7 shows an example of power distribution between the long TTI and the sTTI according to the operation example 1-2. In FIG. 7, SR of sTTI occurs in the section of sTTI # 1.

In this case, the terminal 200 starts transmitting the SR of the sTTI from the sTTI # 2 following the sTTI # 1 in which the SR has occurred. At this time, the terminal 200 has the guaranteed power (Guaranteed power for short TTI) allocated to the sTTI for the transmission of the SR of the sTTI and the surplus power (Remaining power) not used for the transmission of the long TTI. ) Is used. In the example of FIG. 7, the terminal 200 determines that the desired transmission power of the SR is satisfied by three transmissions (3sTTI), and transmits the SR three times using sTTI # 2, sTTI # 3, and sTTI # 4.

The base station 100 recognizes that the SR of the sTTI may be transmitted over a plurality of sTTIs, and performs reception processing even in a pattern in which UL signals of the plurality of sTTIs are added together.

As described above, in the operation example 1-2, even if the UL signal of the sTTI is generated during the transmission of the UL signal with the long TTI, the transmission power of the long TTI is changed only in the subframe unit, so that the TTI with the long sTTI transmission is long. It has the advantage of having little effect on the transmission of. Further, in the operation example 1-2, when the SR occurs, the terminal 200 transmits the SR without waiting, so that the transmission delay of the SR can be suppressed. Further, in the operation example 1-2, since the powers of a plurality of sTTIs can be added together, it is particularly effective when the number of symbols of the sTTI is small.

The operation examples 1-1 and 1-2 when the UL signal is simultaneously transmitted in the long TTI and the sTTI have been described above.

In this way, in the present embodiment, even if the sTTI signal is generated during the transmission of the UL signal of the long TTI, the terminal 200 ensures the reception quality of the UL signal of the long TTI and the long TTI. The UL signal of sTTI is transmitted even during transmission. That is, according to the present embodiment, power distribution can be appropriately performed when UL signals having different TTI lengths are transmitted. Therefore, for example, even when the UL signal spontaneously transmitted by the terminal 200 is transmitted by sTTI without being assigned from the base station 100 (that is, the base station 100 cannot be predicted) as in SR, the UL signal is transmitted. Transmission delay can be suppressed. Further, by suppressing the transmission delay of SR, it is possible to suppress the reduction of user throughput.

In the present embodiment, the case where the minimum guaranteed power is assigned to each of sTTI and TTI has been described, but the transmission power control according to the present embodiment is applied even when the minimum guaranteed power is not assigned. it can. When the minimum guaranteed power is not allocated, the base station 100 may instruct 0% as the minimum guaranteed power, or the system may not set the minimum guaranteed power. If there is no minimum guaranteed power, all power can be used by sTTI, or all power can be used by TTI. Therefore, the amount of increase / decrease in power without the minimum guaranteed power is larger than that with the minimum guaranteed power. Even when there is no minimum guaranteed power, the terminal 200 reduces the transmission power of the TTI UL signal in the middle (in slot units) as shown in FIG. 8 as in the above embodiment, and the sTTI UL signal. Transmission power can be secured.

Further, in the above embodiment, an example in which DMRS is multiplexed on the time axis has been described, but the present invention is not limited to this. For example, even when DMRS is multiplexed on the frequency axis, it is required that the transmission power of the UL signal be constant in the section that refers to the same DMRS. Therefore, when the terminal 200 reduces the power of the UL signal, the UL signal (for example, SR of sTTI) interrupts the transmission of the UL signal while securing the transmission power of DMRS in the symbol. ) May be assigned.

Further, the above embodiment can also be used when actually connected as Dual connectivity. For example, the case where MCG uses TTI and SCG uses sTTI is assumed. Further, in particular, when the MCG and the SCG are serviced by different bearers, the priority is different for each bearer, so it is suitable to apply the above embodiment. Furthermore, if the MCG supports both TTI and sTTI and the SCG supports both TTI and sTTI, it is possible to divide the minimum guaranteed power into four.

(Embodiment 2)
Since the base station and the terminal according to the present embodiment have the same basic configuration as the base station 100 and the terminal 200 according to the first embodiment, FIGS. 3 and 4 will be referred to for description.

In UL, when the terminal 200 simultaneously transmits a UL signal using TTI and sTTI, the total transmission power per symbol during transmission of the UL signal of TTI increases or decreases depending on whether or not the UL signal of sTTI is transmitted. When the transmission power increases or decreases, or when the frequency resource to be transmitted is changed by frequency hopping, it is necessary to set a period (called a Transient period) in which the transmission waveform is allowed to be distorted.

For example, in LTE and LTE-Advanced, a Transient period of 20 μs is set at the beginning and end of the transmission section where the transmission power changes. In addition, if the transmission is continuous but the power changes in the middle, a total Transient period of 40 μs is set. In addition, in the subframe where SRS (Sounding Reference Signal) is transmitted, the Transient period is set outside the period for transmitting SRS (that is, so as not to overlap the interval of SRS) in order to protect SRS. ..

However, in LTE and LTE-Advanced, the setting of Transient period when sTTI transmission occurs in the middle of a subframe and the transmission power changes is not taken into consideration. Therefore, in the present embodiment, the setting of the Transient period when the transmission of sTTI occurs in the middle of the subframe and the transmission power changes will be described.

Hereinafter, operation examples 2-1 and 2-2 of the base station 100 and the terminal 200 according to the present embodiment will be described.

<Operation example 2-1>
In operation example 2-1 the position where the transient period is set when the terminal 200 simultaneously transmits UL signals of long TTI and sTTI will be described.

Specifically, in order to protect the high-priority signal, it is avoided that the high-priority channel and the transient period overlap. For example, assuming that the high priority channel is DMRS or SRS which is a reference signal of UL, the terminal 200 sets the transient period generated by sTTI transmission while avoiding the symbol in which DMRS or SRS of long TTI is arranged.

9A to 9D show a setting example of the Transient period according to the operation example 2-1. 9A-9D show an example in which sTTI is set by dividing the TTI length into four in the case of 14 symbols per subframe in Normal CP. Further, four sTTIs (sTTI # 0 to sTTI # 3) in one subframe are set to 4 symbols, 3 symbols, 4 symbols, and 3 symbols, respectively.

Also, the UL signal transmitted by the long TTI is PUSCH, and DMRS is placed in the 4th OFDM symbol of each slot.

At this time, as shown in FIG. 9A, when the UL signal is transmitted by sTTI # 1, a long TTI DMRS is arranged immediately before the transmission start symbol of sTTI # 1. Therefore, the terminal 200 sets the transient period (40 μs) after the transmission of the DMRS of the long TTI (within the transmission section of the UL signal of the sTTI). Therefore, in the symbol after DMRS (interval of slot # 0, sTTI # 1), it is necessary to allow the waveform to be distorted in the interval of transient period for both sTTI and long TTI. On the other hand, as shown in FIG. 9A, the symbol at which the transmission of sTTI # 1 ends (the last symbol of sTTI # 1) is not adjacent to the DMRS of the long TTI. Therefore, the terminal 200 sets the Transient period (40 μs) after transmitting the sTTI.

Next, as shown in FIG. 9B, when the UL signal is transmitted by sTTI # 2, the DMRS of the long TTI is not arranged immediately before the transmission start symbol of sTTI # 2. Therefore, the terminal 200 sets the Transient period (40 μs) before starting the transmission of sTTI # 2. On the other hand, as shown in FIG. 9B, the last symbol of sTTI # 2 overlaps with the long TTI DMRS. In this case, in order to protect the DMRS, the terminal 200 sets the transient period (40 μs) after the DMRS is transmitted (after the sTTI is transmitted).

Next, as shown in FIG. 9C, when the UL signal is transmitted by sTTI # 3, the DMRS of TTI is arranged immediately before the transmission start symbol of sTTI # 3, so that the terminal 200 is the same as in FIG. 9A. , Set the transient period (40 μs) after the transmission of DMRS of long TTI (within the transmission section of UL signal of sTTI). The rear end of sTTI # 3 is located at the boundary of the subframe. In this case, when transmitting UL signals having different transmission powers in the next subframe, the terminal 200 sets Transient periods (20 μs) before and after the boundary of the subframes.

Further, as shown in FIG. 9D, when the UL signal is transmitted by sTTI # 3 located at the boundary of the subframe and the UL signal is not transmitted at the next subframe, the terminal 200 is connected to the boundary of the subframe. After (that is, after the transmission of sTTI # 3 is completed), set the Transient period (20 μs).

In this way, when UL signals are transmitted simultaneously using the long TTI and sTTI in the terminal 200, the Transient period is in the section other than the symbol where the UL signal with high priority (SRS, DMRS, etc.) is placed in the long TTI. Is set. By doing so, it is possible to protect the UL signal having a high priority. Further, it is preferable that the Transient period is set in the section other than the sTTI section in which the UL signal is transmitted, in addition to the section other than the symbol in which the UL signal having a high priority is arranged. For example, if a Transient period is set in the interval of the sTTI at which the UL signal is transmitted, the effect of signal waveform distortion due to the Transient period extends to both the sTTI and long TTI UL signals. On the other hand, if the Transient period is set in a section other than the sTTI section where the UL signal is transmitted, the signal affected by the distortion of the signal waveform due to the Transient period is only the UL signal of the long TTI.

As shown in FIG. 10, when the TTI transmission is PUCCH format 1a / 1b, DMRS is arranged in the third, fourth, and fifth symbols of each slot. At this time, if the subframe is divided into four and the sTTI is arranged, the boundary of the sTTI (symbols before and after the boundary) may overlap with the DMRS of the long TTI (in FIG. 10, the boundary between sTTI # 0 and sTTI # 1). , And the boundary between sTTI # 2 and sTTI # 3). Therefore, as shown in FIG. 10, when the boundary of the sTTI overlaps with the boundary of two DMRSs of the TTI, the terminal 200 is before and after the boundary of the sTTI so that the influence of the Transient period on each DMRS is averaged. Transient period (20 μs) may be set for each.

<Operation example 2-2>
In operation example 2-1 a case where a long TTI DMRS is protected without considering the position of the sTTI DMRS (hereinafter, also referred to as sDMRS) has been described. On the other hand, in operation example 2-2, the position of DMRS of sTTI is considered.

In sTTI, if the DMRS placement position is inside consecutive symbols in sTTI (that is, it is not the first or last symbol of sTTI), for example, sTTI consists of 4 symbols and the 2nd or 3rd symbol. If DMRS is placed in the eye and frequency hopping is not assumed, there is no change in transmission power before and after the symbol to which DMRS is transmitted. Therefore, in this case, the DMRS of sTTI does not overlap with the transient period.

On the other hand, if DMRS is placed at the first or last symbol of sTTI, DMRS of sTTI may overlap with the transient period. For example, if the DMRS is shared between sTTIs and the DMRS of the sTTI is aligned with the DMRS of the long TTI, the DMRS is placed at the boundary of the sTTI. More specifically, sTTI # 0 is the 1st to 4th symbols, sTTI # 1 is the 4th to 7th symbols, and DMRS is placed in the 4th symbol. At this time, since the DMRS to be protected is common to the long TTI and the sTTI, the terminal 200 may set the Transient period so as not to overlap with the arrangement position of the DMRS, as in the operation example 2-1.

On the other hand, when the DMRS is always placed at the beginning of the sTTI as shown in FIG. 11, the position of the DMRS of the sTTI and the position of the DMRS of the TTI may be consecutively different symbol positions. Therefore, as shown in FIG. 11, in the terminal 200, when the DMRS transmitted by the sTTI # 1 and the DMRS transmitted by the long TTI are continuous, the influence of the Transient period on each DMRS is averaged. Set the Transient period before and after the sTTI boundary.

Further, if the agreement to give priority to the long TTI or give priority to the sTTI is predetermined, the terminal 200 may set the Transient period by avoiding the DMRS section of the priority TTI. That is, the terminal 200 may set the Transient period in the DMRS section of the sTTI when giving priority to the long TTI, and may set the Transient period in the DMRS section of the long TTI when giving priority to the sTTI.

The operation examples 2-1 and 2-2 of the base station 100 and the terminal 200 according to the present embodiment have been described above.

In addition, as the value of the Transient period, 20 μs is set at the beginning and end of the transmission of the transmission power change, and when the transmission is continuous but the power changes in the middle, a total of 40 μs is set. The value of period is not limited to these values.

Also, when frequency hopping is performed within sTTI, it is necessary to set the Spread period before and after frequency hopping. In that case as well, the terminal 200 may set the Transient period so as to protect the high-priority signal in the same manner as in the operation example 2-1 or the operation example 2-2.

Also, when only sTTI transmission is performed, different channels may be transmitted to different frequency resources between consecutive sTTIs. In that case, the priority for each channel is determined in advance like DMRS = SRS> SR> ACK / NACK> CSI> PUSCH without UCI, and the terminal 200 sets the Transient period so that it does not overlap with the transmission of the priority channel. It may be set.

The embodiments of the present disclosure have been described above.

In the above embodiment, as an example of a plurality of TTIs having different TTI lengths, a case where a long TTI is a subframe of LTE and a short TTI is assumed to be an sTTI under consideration in LTE-Advanced has been described. However, a plurality of TTIs having different TTI lengths are not limited to these, and for example, a long TTI and an sTTI may be used as TTIs having different RATs. RAT includes eMBB (enhanced mobile broadband), which is a large-capacity communication, URLL (Ultra-relaible and low latency communications), which is ultra-high reliability and low latency communication, and mMTC (Massive machine-type communications), which is multi-terminal communication. ) Etc. are possible. In addition, LTE and LTE-Advanced can also be considered as one of RAT. Since the suitable TTI length differs for each RAT, it is possible that the TTI length differs depending on the RAT. It is also possible that the TTI length will be different for each of the multiple systems in the RAT. Further, in the above embodiment, the interval of 1 msec is called a subframe, but the present invention is not limited to this, and in different RATs, the reference 1 msec interval may be referred to by another name.

Further, in the above embodiment, the long TTI and sTTI may be physically assigned to the same component carrier or may be assigned to different component carriers. Therefore, physically, a long TTI PUCCH / PUSCH and an sTTI PUCCH / PUSCH may be transmitted simultaneously to the same component carrier. However, from the viewpoint of transmission power control and data allocation, long TTIs and sTTIs are treated as separate cells for transmission power control, and each TTI is UL unaffected by the channels of other TTIs. The placement of control channels can be determined.

Further, a system using a long TTI may be a system having a narrow subcarrier spacing and a long symbol spacing, and a system using a short TTI (sTTI) may be a system having a wide subcarrier spacing and a short symbol spacing. In LTE and LTE-Advanced, when the subcarrier interval is 15 KHz and Normal CP, 1 msec is divided into 14 symbols. For example, when the subcarrier interval is 60 kHz, the symbol length can be set short, and the number of symbols accommodated per 1 msec increases. In this case, the TTI length can be easily set short. Therefore, the above embodiment can be applied to a terminal that uses a long TTI when the subcarrier interval is narrow and a short TTI when the subcarrier interval is wide and simultaneously transmits them.

Further, in the above embodiment, the case where the TTI (long TTI) is 1 msec has been described, but the TTI length is not limited to this, and UL signals are simultaneously transmitted using TTIs having different TTI lengths. In this case, the above embodiment can be applied.

Further, in the above-described embodiment, the case where one aspect of the present disclosure is configured by hardware has been described as an example, but the present disclosure can also be realized by software in cooperation with hardware.

Further, each functional block used in the description of the above embodiment is typically realized as an LSI which is an integrated circuit having an input terminal and an output terminal. The integrated circuit may control each functional block used in the description of the above embodiment and may include an input terminal and an output terminal. These may be individually integrated into one chip, or may be integrated into one chip so as to include a part or all of them. Although it is referred to as LSI here, it may be referred to as IC, system LSI, super LSI, or ultra LSI depending on the degree of integration.

Further, the method of making an integrated circuit is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. An FPGA (Field Programmable Gate Array) that can be programmed after the LSI is manufactured, or a reconfigurable processor that can reconfigure the connection and settings of circuit cells inside the LSI may be used.

Furthermore, if an integrated circuit technology that replaces an LSI appears due to advances in semiconductor technology or another technology derived from it, it is naturally possible to integrate functional blocks using that technology. There is a possibility of applying biotechnology.

When the terminal of the present disclosure generates an uplink signal of a second TTI whose TTI length is shorter than that of the first TTI while transmitting an uplink signal in the first section that refers to the first reference signal within the first TTI (Transmission Time Interval). , In the first section, the transmission power of the first reference signal and the uplink signal of the first TTI is kept constant, the transmission power is not allocated to the uplink signal of the second TTI, and the transmission power is followed in the first TTI, and the second reference In the second section that refers to the signal, the transmission power of the uplink signal of the first TTI and the second TTI is determined so as to reduce the transmission power of the uplink signal of the first TTI and allocate the transmission power to the uplink signal of the second TTI, respectively. It includes a transmission power determination unit and a transmission unit that transmits uplink signals of the first TTI and the second TTI with the determined transmission power.

In the terminal of the present disclosure, the uplink signal of the second TTI has a higher priority than the uplink signal of the first TTI.

In the terminal of the present disclosure, the uplink signal of the second TTI is SR (Scheduling Request).

In the terminal of the present disclosure, when the modulation method used in the first TTI is a multi-value modulation method using amplitude, the reference signal is not shared in the first section and the second section in the first TTI, and the uplink signal of the first TTI is not shared. Is demodulated independently in each section of the first section and the second section in the base station.

In the terminal of the present disclosure, when the uplink signal is simultaneously transmitted by the terminal using the first TTI and the second TTI, the Transient period is set in the section other than the symbol in which the uplink signal having a high priority is arranged in the first TTI. ..

In the terminal of the present disclosure, the Transient period is set to a section other than the second TTI at which the uplink signal is transmitted.

In the terminal of the present disclosure, the upstream channel signal having a high priority is SRS (Sounding Reference Signal) or DMRS (Demodulation Reference Signal).

In the communication method of the present disclosure, while the uplink signal is transmitted in the first section that refers to the first reference signal within the first TTI (Transmission Time Interval), the uplink signal of the second TTI having a TTI length shorter than that of the first TTI is generated. In the case, in the first section, the transmission power of the first reference signal and the uplink signal of the first TTI is kept constant, the transmission power is not allocated to the uplink signal of the second TTI, the transmission power is not allocated to the uplink signal of the second TTI, the transmission power is succeeded in the first section, and the second In the second section that refers to the reference signal, the transmission power of the uplink signal of the first TTI and the second TTI is determined so as to reduce the transmission power of the uplink signal of the first TTI and allocate the transmission power to the uplink signal of the second TTI, respectively. Then, the uplink signals of the first TTI and the second TTI are transmitted with the determined transmission power.

One aspect of the present disclosure is useful for mobile communication systems.

100 Base station 101 DCI generator 102, 208 Error correction coding unit 103, 209 Modulation unit 104, 210 Signal allocation unit 105, 212 Transmission unit 106, 201 Reception unit 107, 202 Signal separation unit 108 ACK / NACK reception unit 109, 203 Demodulation unit 110, 204 Error correction decoding unit 200 Terminal 205 Error judgment unit 206 ACK / NACK generation unit 207 DCI reception unit 211 Transmission power determination unit

Claims (11)

In the first TTI (Transmission Time Interval) for transmitting the first uplink signal, when the second uplink signal is transmitted at the second TTI shorter than the first TTI, the transmission power is preferentially allocated to the second uplink signal. A transmission power determination unit that determines the transmission power of the first uplink signal and the second uplink signal, respectively.
A transmission unit that transmits the first uplink signal and the second uplink signal with the determined transmission power, and a transmission unit.
A terminal equipped with. The second uplink signal has a higher priority than the first uplink signal.
The terminal according to claim 1. The second uplink signal includes SR (Scheduling Request) or HARQ-ACK, and the first uplink signal is a PUSCH that does not include uplink control information.
The terminal according to claim 1. The first TTI includes a first section and a second section, and the transmission power can be changed in the first section and the second section.
The terminal according to claim 1. The first TTI includes a first section and a second section, which are units for setting transmission power.
The terminal according to claim 1. The second uplink signal is transmitted in the second section.
The terminal according to claim 4 or 5. The reference signal is not shared in the first section and the second section.
The terminal according to any one of claims 4 to 6. A Transient period for the second uplink signal is set in a section other than the symbol in which the uplink signal having a high priority is arranged in the first TTI.
The terminal according to claim 1. The Transient period is set to a section other than the second TTI.
The terminal according to claim 8. The high-priority uplink signal is SRS (Sounding Reference Signal) or DMRS (Demodulation Reference Signal).
The terminal according to claim 8 or 9. In the first TTI (Transmission Time Interval) for transmitting the first uplink signal, when the second uplink signal is transmitted at the second TTI shorter than the first TTI, the transmission power is preferentially allocated to the second uplink signal. The transmission power of the first uplink signal and the second uplink signal is determined, respectively.
The first uplink signal and the second uplink signal are transmitted with the determined transmission power.
Communication method.

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