WO2016182038A1 - Terminal device and base station device - Google Patents

Abstract

There has been a problem in that a terminal device requires a given number of decoding times for the detection of control information including frequency resource allocation, and the overhead required for data transmission from a subframe for which control information including uplink frequency resource allocation has been detected cannot be reduced. Provided is a base station device that receives a signal transmitted from a terminal device, said base station device having: a low-latency transmission management unit that stores information on whether the terminal device uses first data transmission whereby low-latency data transmission is performed or second data transmission whereby non-low-latency data transmission is performed; a control signal generation unit that generates first control information that includes information relating to resource allocation used at the time of the first data transmission; and a control information allocation unit that allocates second control information, which includes a transmission parameter used in data transmission, to a resource. At the time of the first data transmission, the control information allocation unit allocates the control information on the basis of the first control information.

Description

Terminal apparatus and base station apparatus

The present invention relates to a terminal device and a base station device.

In mobile communication systems, 3GPP (Third Generation Partnership Project) LTE (Long Term Evolution) and LTE-A (LTE-Advanced) CA (Carrier Aggregation) technology that realizes wide bandwidth And techniques for improving peak data rates such as MIMO (Multiple Input Multiple Output) have been standardized.

Also, 3GPP LTE Rel. 8 achieves low-delay transmission compared to previous releases, but MTC for special applications that require remote operation or remote operation of vehicles, or low-delay transmission, which is considered to be used in future LTE communication systems. Real-time applications such as Machine Type Communication (also called Machine-to-Machine Communication) require data transmission with a lower delay than the present time.

Therefore, as a method for realizing low-delay transmission, TTI (Transmission Time Interval), which is a unit of data transmission once while satisfying backward compatibility, is reduced to half of the conventional method, or an uplink (from a terminal device to a base station device) in advance. A method has been studied in which information related to communication (hereinafter referred to as uplink) is notified to shorten the time required from data generation to data transmission (Non-patent Document 1).

In uplink transmission in the current LTE and LTE-A systems, a frequency resource used for uplink transmission to the base station apparatus is transmitted by transmitting a SR (Scheduling Request) after the terminal apparatus generates data to be transmitted in the uplink. Request an assignment. The terminal apparatus monitors PDCCH (Physical Downlink Control Control CHannel) and EPDCCH (Enhanced PDCCH) to which DCI (also referred to as Downlink Control Information and UL grant) of control information including frequency resource allocation is transmitted by blind decoding. After detecting control information including uplink frequency resource allocation, the terminal apparatus performs uplink data transmission four subframes after the subframe in which the control information is detected.

Ericsson, Huawei, “New SI proposal: alStudy on Latency reduction techniques for LTE,” RP-150465, 3GPP, March 2015

However, blind decoding used by terminal equipment to detect control information including frequency resource allocation requires a certain number of blind decoding times for each component carrier (also called CC: Component Carrier or Serving cell). There is a problem that the overhead required for data transmission cannot be reduced from a subframe in which control information including link frequency resource allocation is detected.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a communication method in which a terminal device can reduce overhead required for data transmission from occurrence of uplink data.

(1) The present invention has been made to solve the above problems, and one aspect of the present invention is a base station device that receives a data signal transmitted from a terminal device, and the terminal device has low delay. A low-delay transmission management unit for holding information on which one of the first data transmission for performing the data transmission and the second data transmission for the terminal device to perform the data transmission without a low delay, and at the time of the first data transmission A control signal generation unit that generates first control information including information on resource allocation to be used; and a control information allocation unit that allocates second control information including a transmission parameter used for data transmission by the terminal device to resources. The control information allocation unit allocates the control information based on information on the resource allocation included in the first control information when transmitting the first data.

(2) Further, according to one aspect of the present invention, the information on the resource allocation included in the first control information is information specifying a search space.

(3) Further, according to one aspect of the present invention, the information on the resource allocation included in the first control information is information specifying PDCCH or EPDCCH.

(4) Further, according to one aspect of the present invention, the information related to resource allocation included in the first control information is information specifying an aggregation level.

(5) Further, according to one aspect of the present invention, the information on the resource allocation included in the first control information is information specifying a payload size.

(6) Further, according to one aspect of the present invention, the information on the resource allocation included in the first control information is information specifying a component carrier.

(7) One embodiment of the present invention is a terminal device that transmits a data signal to a base station device, wherein the first data transmission that performs data transmission with low delay or the data transmission in which the terminal device is not low delay A transmission processing unit that transmits data in any of the second data transmissions, a control information storage unit that holds information about resource allocation used in the first data transmission notified by the first control information, A control information detection unit that detects second control information including a transmission parameter used in either the first data transmission or the second data transmission, and the control information detection unit is configured to perform the second control. Among the resources where information may be arranged, the resource notified by the first control information is preferentially detected.

(8) Further, according to one aspect of the present invention, the information on resource allocation used at the time of the first data transmission notified by the first control information specifies information specifying a search space, PDCCH or EPDCCH. It includes at least one of information, information specifying an aggregation level, information specifying a payload size, and information specifying a component carrier.

According to the present invention, it is possible to reduce the overhead required for data transmission from the occurrence of uplink data by the terminal device.

It is a figure which shows an example of a structure of the system which concerns on this invention. It is a figure which shows an example of a structure of the terminal device which concerns on this invention. It is a figure which shows an example of a structure of the transmission signal generation part 101 which concerns on this invention. It is a figure which shows an example of the sequence chart of the conventional uplink transmission in this invention. It is a figure which shows an example of the sequence chart of the uplink transmission which concerns on this invention. It is a figure which shows an example of a structure of the base station apparatus which concerns on this invention. It is a figure which shows an example of a structure of the signal separation part 204 which concerns on this invention. It is a figure which shows an example of a structure of the signal detection part 205 which concerns on this invention. It is a figure which shows an example of the candidate of the blind decoding which concerns on this invention. It is a figure which shows an example of the sequence chart of the uplink transmission which concerns on this invention. It is a figure which shows an example of a structure of the base station apparatus which concerns on this invention. It is a figure which shows an example of a structure of the signal separation part 204 which concerns on this invention. It is a figure which shows an example of a structure of the terminal device which concerns on this invention. It is a figure which shows an example of a structure of the transmission signal generation part 101 which concerns on this invention.

Hereinafter, embodiments will be described with reference to the drawings. In each of the following embodiments, the communication system includes a base station device (transmitting device, cell, transmission point, transmitting antenna group, transmitting antenna port group, component carrier, serving cell, eNodeB, Pico eNodeB, small cell, RRH: Radio Remote Head , LPN: Low Power Node) and a terminal device (terminal, mobile terminal, receiving point, receiving terminal, receiving device, receiving antenna group, receiving antenna port group, UE: User Equipment). Also, in this specification, it is assumed that the single antenna transmission of uplink (communication from the terminal apparatus to the base station apparatus, hereinafter referred to as uplink) is assumed, but the present invention is applied to a single user MIMO (Multiple Multiplex transmission). Input Multiple Output) or multiple terminal devices may be applied to multi-user MIMO using the same time and frequency resources. Further, the present invention may be applied not only to transmission of control information between a base station apparatus and a terminal apparatus, but also to communication between a base station apparatus and a relay station apparatus, between a relay station apparatus and a terminal apparatus, or between terminals.

FIG. 1 shows an example of the configuration of a system according to the present invention. The system includes a base station apparatus 10 and terminal apparatuses 21 to 25. In addition, the number of terminal devices is not limited to this example, and the number of antennas of each device may be one or plural. In addition, the base station apparatus 10 may perform communication using a so-called licensed band obtained from the country or region where the wireless provider provides the service, or use permission from the country or region. Communication using a so-called unlicensed band that is not required may be performed. The base station apparatus 10 may be a macro base station apparatus with a wide coverage, or a pico base station apparatus (PicoPeNB: evolved Node B, Small Cell, Low Power Node, Remote, which has a narrower coverage than the macro base station device. It may also be called RadioadHead). In this specification, the frequency band other than the license band is not limited to the example of the unlicensed band, and may be a white band (white space) or the like. Further, the base station apparatus 10 may apply a CA (Carrier-Aggregation) technique that uses a plurality of component carriers (CC: also referred to as "Component Carrier" or Serving "cell") in a band used in LTE communication.

The base station apparatus 10 transmits a data signal of a downlink (communication from the base station apparatus to a terminal apparatus, hereinafter referred to as a downlink) by PDSCH (Physical Downlink Shared CHannel) and includes a transmission parameter used for the data signal. Information is transmitted by PDCCH (Physical Downlink Control CHannel) or EPDCCH (Enhanced PDCCH). The terminal devices 21 to 25 detect DCI (also referred to as Downlink Control Information, DL grant) of control information notified by PDCCH or EPDCCH by blind decoding, and down-convert based on transmission parameters included in DCI Link data signals are detected. In uplink transmission, the terminal devices 21 to 25 blindly transmit DCI (also referred to as UL grant when reporting transmission parameters of uplink transmission) transmitted from the base station device 10 by PDCCH or EPDCCH. Data transmission in uplink transmission is performed based on transmission parameters detected by decoding and included in DCI. Data transmission in uplink transmission is transmitted by PUSCH (Physical Uplink Shared CHannel), and control information of uplink transmission such as ACK / NACK (Acknowledgement / Negative Acknowledgement) and propagation path for SR (Scheduling Request) and downlink data Quality information (CSI: “Channel State Information”) is transmitted by PUCCH (Physical Uplink Control Control CHannel).

Here, the base station apparatus 10 classifies the terminal apparatus that requires low-delay uplink transmission and the terminal apparatus that does not require low-delay uplink transmission from the control information transmitted from each terminal apparatus. . The base station apparatus 10 notifies in advance information regarding frequency resource allocation in uplink transmission to a terminal apparatus that requires uplink transmission with low delay. When a frequency resource allocation request is received from a terminal device requiring low-delay uplink transmission using SR (Scheduling Request) or RACH (Random Access Access CHannel), the base station apparatus 10 is based on information about frequency resource allocation notified in advance. Control information for low delay transmission. On the other hand, the base station apparatus 10 determines a frequency resource used for uplink data transmission to each terminal apparatus by frequency scheduling. A terminal apparatus that requires low-delay uplink transmission performs brand decoding based on information about frequency resource allocation for low-delay transmission notified from the base station apparatus. When control information for low-delay transmission is detected, data transmission is performed by shortening the interval from the subframe in which the terminal apparatus detects control information including frequency resource allocation in uplink transmission to the subframe in which data transmission is performed. . In the following embodiments, a method for realizing data transmission with a short interval from a subframe in which control information including frequency resource allocation in uplink transmission is detected to a subframe in which data transmission is performed will be described.

The low-delay transmission according to the present invention may reduce the overhead required from the generation of transmission data at the terminal device to the data transmission, or the ACK / NACK for data transmission after the transmission data is generated at the terminal device. You may reduce the overhead until a device receives. The low-delay transmission according to the present invention may be realized by a method in which the terminal apparatus transmits data without performing SR transmission or UL Grant reception after transmission data is generated in the terminal apparatus. In the low delay transmission according to the present invention, a subframe or slot capable of low delay transmission is set in advance, and the terminal apparatus does not perform SR transmission or UL Grant reception only in the subframe or slot capable of low delay transmission. It may be realized by a method of performing data transmission. The low-delay transmission according to the present invention transmits data with low overhead when a subframe or slot capable of scheduling low-delay transmission is preset and UL Grant is received in a subframe or slot capable of low-delay transmission. It may be realized by doing. In the low delay transmission according to the present invention, the TTI may be shortened from the conventional 1 msec (subframe unit), and for example, scheduling, data transmission, and ACK / NACK transmission may be performed in 0.5 msec (slot unit).

(First embodiment)
FIG. 2 shows an example of the configuration of the terminal device according to the present invention. However, the minimum blocks necessary for the present invention are shown. In the figure, for the sake of simplicity of explanation, each terminal apparatus has one transmission / reception antenna. However, a plurality of transmission antennas may be used to perform the same processing, and a plurality of reception antennas may be used. And receiving antenna diversity may be performed. The terminal apparatus receives a signal transmitted from the base station apparatus via PDCCH, EPDCCH, or PDSCH by the reception antenna 106 and inputs the signal to the radio reception unit 107. The wireless reception unit 107 down-converts the received signal to a baseband frequency, performs A / D (Analog / Digital) conversion, and removes a CP (Cyclic Prefix) from the digital signal. To enter. The control information detection unit 108 converts the input received signal sequence from a time domain signal sequence to a frequency domain signal sequence by fast Fourier transform, and sets up a CSS (Common Search Space) or USS (UE) set in the PDCCH or EPDCCH. -specific Search Space), the control information is detected by blind decoding the DCI format. Here, the DCI format detected by brand decoding is determined by the downlink transmission mode and the setting of RRC (Radio Resource Control).

Here, a plurality of formats are defined for the DCI format depending on the application. The DCI format 1 for a single antenna for downlink transmission, the DCI format 1A for transmission diversity, and the DCI formats 1B, 2, 2B for SU-MIMO. DCI format 2A for 2C, Large Delay CDD (Cyclic Delay Diversity), DCI format 2C for MU-MIMO and DCI format 2D for downlink cooperative communication are defined, and DCI for single antenna for uplink transmission Format 0 and DCI format 4 for MIMO are defined. The control information detector 108 performs blind decoding of CSS and USS a predetermined number of times, and tries to detect a DCI format for downlink transmission or uplink transmission. In addition, when the information for low-delay transmission is received in advance, the control information detection unit 108 receives information about frequency resource allocation for low-delay transmission from the control information storage unit 109, and the frequency resource for low-delay transmission Blind decoding is performed based on the information regarding allocation. Details will be described later. When control information is detected by blind decoding, the control information detection unit 108 allocates resources (RA: Resource Allocation or Resource Assignment, hereinafter referred to as RA information) or MCS (Modulation and Coding) notified in the DCI format. Scheme) and the transmission power control value are output to the transmission signal generator 101. In addition, when control information is received by RRC signaling of higher-layer control information on PDSCH, control information detection section 108 detects by control information reception processing. Here, the control information notified by RRC signaling includes information on downlink transmission mode, information on whether or not to perform uplink MIMO transmission, information on frequency resource allocation for low-delay transmission, and the like. In addition, when receiving information related to frequency resource allocation for low-delay transmission, the control information detection unit 108 inputs the information to the control information storage unit 109.

The transmission signal generation unit 101 receives a transmission parameter detected by blind decoding and a data bit string to be transmitted by uplink transmission. FIG. 3 shows an example of the configuration of the transmission signal generation unit 101 according to the present invention. As shown in the figure, the input data bit string is input to the error correction encoding unit 1011. The error correction encoding unit 1011 performs encoding of an error correction code on the input data bit string. For example, a turbo code, an LDPC (Low Density Parity Check) code, a convolutional code, or the like is used as the error correction code. The type of error correction code applied by error correction encoding section 1011 may be determined in advance by the transmission / reception apparatus, may be notified as control information for each transmission / reception opportunity, or determined in advance according to the transmission mode. Switching may be performed according to the notified parameter and the parameter notified by the control information. The coding rate of error correction coding is input from the control information detection unit 108, and the error correction coding unit 1011 realizes the coding rate used for downlink data transmission by puncturing (rate matching).

The modulation unit 1012 receives modulation scheme information from the control information detection unit 108 and modulates the encoded bit sequence input from the error correction encoding unit 1011 to generate a modulation symbol sequence. Examples of the modulation scheme include QPSK (Quaternary Phase Shift Keying), 16 QAM (16-ary Quadrature Amplitude Modulation), 64 QAM, and 256 QAM. Modulation section 1012 outputs the generated modulation symbol sequence to DFT section 1013. The DFT unit 1013 performs discrete Fourier transform on the input modulation symbol to convert the time domain signal into a frequency domain signal, and outputs the obtained frequency domain signal to the transmission signal allocation unit 1014.

The transmission signal allocation unit 1014 receives a transmission signal sequence from the DFT unit 1013 and further receives RA information from the control information detection unit 108. The transmission signal allocation unit 1014 allocates a transmission signal sequence based on the RA information. The frequency resource allocation is RB (Resource Block) composed of 12 subcarriers of 1 TTI (one slot composed of 7 OFDM symbols or one subframe composed of 14 OFDM symbols or a unit composed of one or more OFDM symbols). ) An example performed in units or RBG (Resource 単 位 Block も し く は Group) in which a plurality of RBs are grouped will be described. The RA information may indicate a continuous RB (or RBG) or a discontinuous RBG (or RB). The reference signal multiplexing unit 1015 receives a frequency domain data signal sequence from the transmission signal allocation unit 1014, receives a reference signal sequence from the reference signal generation unit 1016, and multiplexes these signal sequences, thereby transmitting a transmission signal frame Is generated. However, the reference signal multiplexing unit 1015 may multiplex the data signal and the reference signal in the time domain. The reference signal multiplexed by the reference signal multiplexing unit 1015 includes a DMRS (De-Modulation Reference Signal) used by the base station apparatus for demodulating data signals for uplink transmission and a base station apparatus for estimating the frequency response of uplink transmission. There is SRS (Sounding Reference Signal) to be used.

On the other hand, the control signal generation unit 1018 generates propagation path quality information (CSI: Channel State Information), SR (Scheduling 、 Request), and ACK / NACK (Acknowledgement / Negative Acknowledgement) of control information of uplink transmission transmitted by PUCCH. To the control information multiplexing unit 1017. In addition, when low delay transmission is necessary, the control signal generation unit 1018 needs to receive information on frequency resource allocation in uplink transmission from the base station device in advance, and thus generates a setting request for low delay transmission. The control information multiplexing unit 1017 multiplexes the data signal and control information. However, at the transmission timing of only one of the data signal and the control information, the transmission is a transmission in which the data signal is arranged on the PUSCH or the transmission in which the control information is arranged on the PUCCH or the PUSCH. The control information arranged in the PUSCH includes PH (Power Headroom). In addition, in a terminal device that cannot simultaneously transmit control information transmitted on PUCCH and a signal transmitted on PUSCH, control information transmitted on PUCCH and a signal transmitted on PUSCH have the same timing (the same subframe or the same slot or the same). In the case of transmission by TTI), only control information transmitted by PUCCH is transmitted.

The IFFT unit 102 receives a frame of a transmission signal in the frequency domain, and converts the frequency domain signal sequence into a time domain signal sequence by performing inverse fast Fourier transform for each OFDM symbol. The transmission power control unit 103 performs transmission power control according to the transmission power control value input from the control information detection unit 108 and outputs the transmission power to the transmission processing unit 104. The transmission processing unit 104 inserts a CP into the signal sequence, converts the signal into an analog signal by D / A (Digital / Analog), and up-converts the converted signal to a radio frequency used for transmission. The transmission processing unit 104 amplifies the up-converted signal with PA (Power Amplifier), and transmits the amplified signal via the transmission antenna 105. As described above, the terminal device transmits a DFTS-OFDM (also called Discrete-Fourier-Transform-Spread-Orthogonal-Frequency-Division-Multiplexing, SC-FDMA) signal. However, the terminal apparatus may perform data transmission by OFDM, and in this case, the DFT unit 1013 is not necessary.

Here, FIG. 4 shows an example of a sequence chart of conventional uplink transmission. First, the base station apparatus transmits information including resources for SR transmission, information related to transmission power control, and the like using upper layer control information (for example, RRC) (S100). When data for uplink transmission occurs and the terminal device does not receive UL Grant, the terminal device transmits SR to request UL Grant (S101). After receiving the SR, the base station device transmits UL Grant using PDCCH or EPDCCH to the terminal device using subframe k (S102). The terminal device receives UL Grant by performing blind decoding of PDCCH and EPDCCH after SR transmission. In the case of FDD (also called Frequency と も Duplex or frame structure type1), the terminal device transmits data based on the transmission parameters included in UL Grant in subframe k + 4 after detecting UL Grant by blind decoding of PDCCH and EPDCCH. (S103). However, in the case of TDD (also referred to as Time Division Duplex or frame structure2type2), subframe k + 4 is not necessarily a subframe in which uplink transmission is possible, and therefore data transmission of a subframe different from subframe k + 4 is performed. Sometimes. Hereinafter, for the sake of simplicity, the description is limited to the case of FDD, but the present invention is also applicable to TDD. The base station apparatus detects the data transmitted by the terminal apparatus, and transmits ACK / NACK indicating whether or not there is an error in the data detected in subframe k + 8 (S104). Here, in S101, when the resource for SR transmission is not notified by RRC, the terminal device requests UL Grant using RACH (Random Access CHannel). In S102, in the case of dynamic scheduling, data transmission of only one subframe is possible, but in the case of SPS (Semi-Persistent Scheduling), periodic data transmission is permitted, and information such as the SPS cycle is provided in S100. It shall be notified by RRC.

FIG. 5 shows an example of a sequence chart of uplink transmission in the present invention. This figure shows a case where the terminal device performs low-delay transmission. In addition to the upper layer control information (for example, RRC signaling) transmitted in S100 of FIG. 4, the base station apparatus transmits information on frequency resource allocation in uplink transmission to be notified in advance as information for low delay transmission. (S200). When data for uplink transmission occurs and the terminal device does not receive UL Grant, the terminal device transmits SR to request UL Grant (S201). After receiving the SR, the base station apparatus transmits UL Grant using PDCCH or EPDCCH to the terminal apparatus using subframe k by a method described later (S202). The terminal apparatus performs data transmission based on transmission parameters included in UL Grant in subframe k + d after detecting UL Grant by blind decoding of PDCCH and EPDCCH (S203). However, this is a case of lower delay transmission than in the conventional case, and d ≦ 4. The base station apparatus detects the data transmitted by the terminal apparatus and transmits ACK / NACK indicating whether or not the detected data has an error in subframe k + d + h (S204). However, this is a case of transmission with lower delay than in the prior art, and h ≦ 4. As described above, if d <4, the overhead from the data generation to the data transmission by the terminal device can be shortened as compared with the conventional case, and if d + h <8, the terminal device from the data generation to the data transmission. The overhead until receiving the ACK / NACK can be shortened compared to the conventional case.

FIG. 6 shows an example of the configuration of the base station apparatus according to the present invention. However, the minimum blocks necessary for the present invention are shown. In the figure, for the sake of simplicity of explanation, a single transmitting / receiving antenna of the base station apparatus is described, but a plurality of transmitting / receiving antennas may be provided. The base station apparatus receives a signal transmitted by uplink using the reception antenna 201 and inputs the signal to the reception processing unit 202. The reception processing unit 202 down-converts the received signal to the baseband frequency, performs A / D conversion, and removes the CP from the digital signal. Reception processing section 202 outputs the signal after CP removal to FFT section 203. The FFT unit 203 converts the input received signal sequence from a time domain signal sequence to a frequency domain signal sequence by fast Fourier transform, and outputs the frequency domain signal sequence to the signal separation unit 204.

FIG. 7 shows an example of the configuration of the signal separation unit 204 according to the present invention. In the figure, in the signal separation unit 204, the frequency domain signal sequence input from the FFT unit 203 is input to the reference signal separation unit 2041. The reference signal separation unit 2041 separates the signal into SRS and DMRS and other signals, and outputs them to the channel estimation unit 206 and the control information separation unit 2042, respectively. Control information demultiplexing section 2042 demultiplexes the input signal into a control signal transmitted through PUCCH and PUSCH and a data signal transmitted through PUSCH, and outputs them to control information detection section 2044 and assignment signal extraction section 2043, respectively. The control information detection unit 2044 detects control information transmitted on the PUCCH and control information such as PH transmitted on the PUSCH from the received signal, and inputs the control information to the radio resource control unit 210. The allocation signal extraction unit 2043 extracts a desired signal based on the RA information notified to the terminal device as control information, and inputs it to the signal detection unit 205.

The propagation path estimation unit 206 outputs the estimated frequency response to the signal detection unit 205 when DMRS for data demodulation is input. Moreover, the propagation path estimation part 206 estimates the frequency response used for the frequency scheduling of uplink transmission, when SRS is input, and inputs an estimated value into the radio | wireless resource control part 210. FIG. Radio resource control section 210 determines frequency resource allocation based on frequency response and PH estimated from SRS as frequency scheduling for uplink transmission, received SR, and ACK / NACK of the decoding result of the signal received in the previous subframe. . The frequency resource allocation will be described on the assumption that it is performed in RB units or RBG units composed of 12 subcarriers of 1 TTI (unit composed of 1 slot or 1 subframe or 1 or more OFDM symbols). The present invention is not limited to this. Here, one subframe is composed of 2 slots, and one slot is composed of 7 OFDM symbols. However, the present invention is not limited to this example. The radio resource control unit 210 is also referred to as resource allocation (RA: Resource Allocation or Resource Assignment, hereinafter referred to as RA information) or adaptive modulation and coding (Adaptive Modulation and Coding, link adaptation) in frequency scheduling. ) Determines the application of MCS (Modulation and Coding Scheme) or MIMO (Multiple Input to Multiple Output) transmission, and the number of streams (number of layers) in the case of MIMO transmission. The radio resource control unit 210 inputs RA information, MCS, and number of streams information to the control information generation unit 207.

The control information generation unit 207 generates, for each terminal device, control information according to the DCI format determined according to whether or not uplink MIMO of each terminal device is applied to the input control information. In addition, when generating control information for downlink transmission, the control information generation unit 207 generates control information for each terminal device according to the DCI format determined by the setting of the downlink transmission mode and RRC (Radio Resource Control). To do. The control information generation unit 207 inputs control information based on the generated DCI format to the control information allocation unit 212 in order to arrange and transmit the control information in the CSS or USS of the PDCCH or EPDCCH. The control information generation unit 207 inputs the generated information on the destination terminal device in the DCI format to the low delay transmission management unit 211. In addition, when notifying information on frequency resource allocation for low-delay transmission by RRC signaling, the control information generation unit 207 inputs information on a terminal apparatus that requires low-delay uplink transmission to the low-delay transmission management unit 211. . However, although the present invention has been described for the case where it is applied to an existing transmission mode for uplink transmission, there is a transmission mode for low-delay uplink transmission, and the base station apparatus uses control information for low-delay transmission. The information of the terminal apparatus that has set the transmission mode of the uplink transmission may be input to the low-delay transmission management unit 211.

The low-delay transmission management unit 211 holds information when information on a terminal device that requires low-delay uplink transmission is input. The low-delay transmission management unit 211 identifies whether or not a terminal device that requires uplink transmission with low delay is included when the information of the generated terminal device in the DCI format is input, and the DCI format Information of a terminal apparatus that requires a low-delay uplink transmission and a low-delay destination is input to the control information allocation unit 212. The control information allocating unit 212 arranges the DCI format input to the CSS or USS of the PDCCH or EPDCCH by a method to be described later based on information on whether or not the destination terminal device needs low-delay uplink transmission. The control information transmitting unit 208 inserts a CP after converting the frequency domain signal sequence into a time domain signal, converts it into an analog signal by D / A, and upconverts the converted signal to a radio frequency used for transmission. . Control information transmission section 208 amplifies the upconverted signal with PA, and transmits the amplified signal via transmission antenna 209. Here, although not shown in the configuration example of the base station apparatus, a data signal for downlink transmission to be transmitted by PDSCH is also generated, and is multiplexed with control information and a reference signal to be transmitted by PDCCH or EPDCCH and transmitted. Here, downlink reference signals include CRS (Cell-Specific Reference Signal), URS (UE-Specific Reference Signal) related to PDSCH, DMRS (De-Modulation Reference Signal) related to EPDCCH, NZP CSI-RS ( Non-Zero Power Channel State Information Reference Signal), ZP CSI-RS (Zero Power Channel State Information Reference Signal) and DRS (Discovery Reference Signal, Discovery Signal).

FIG. 8 shows an example of the configuration of the signal detection unit 205 according to the present invention. In the signal detection unit 205, the data signal sequence input from the signal separation unit 204 is input to the equalization unit 2051. The equalization unit 2051 generates equalization weights based on the MMSE norm of the desired signal from the frequency response estimation value input from the propagation path estimation unit 206, and multiplies the desired signal. The equalization unit 2051 outputs the signal for each terminal device after equalization to the IDFT units 2052-1 to 2052-U. IDFT sections 2052-1 to 2052-U convert the received signal after frequency domain equalization into a time domain signal. Although not shown, the demodulation units 2053-1 to 2053-U receive information of a modulation scheme that has been notified in advance or is determined in advance, and performs demodulation processing on the received signal sequence in the time domain, A bit sequence LLR (Log Likelihood Ratio), that is, an LLR sequence is obtained.

Although not shown, decoding sections 2054-1 to 2054-U receive information of a coding rate that has been notified in advance or is determined in advance, and performs a decoding process on the LLR sequence. Decoding sections 2054-1 to 2054-U make a hard decision on the decoded LLR sequence, determine the presence / absence of an error bit by cyclic redundancy check (CRC: Cyclic Redundancy Check), and perform radio resource control on the presence / absence of error bit To the unit 210. Here, in the reception processing of the present embodiment, the case where an interference canceller is not applied has been described for the sake of simplicity. However, signal detection is performed by using a successive interference canceller (SIC: Successive Interference Canceller) or turbo equalization that performs repetitive processing. May be. In that case, the decoding units 2054-1 to 2054-U output the external LLR or the posterior LLR output from the decoder to a soft replica generation unit (not shown). Here, the difference between the external LLR and the posterior LLR is whether or not the prior LLR inputted to the decoding units 2054-1 to 2054-U is subtracted from the decoded LLR. The soft replica generation unit generates a symbol replica from the input LLR sequence according to the modulation scheme used by the terminal device for data transmission, converts the symbol replica into a frequency domain signal by DFT, and is used by each terminal device A soft replica is generated by assigning a signal to a resource and multiplying the frequency response. A cancellation processing unit (not shown) performs a cancellation process on the received signal by subtracting the soft replica from the signal sequence input to the equalization unit 2051 and inputs the received signal to the equalization unit 2051. The processing after the equalization unit 2051 is the same, and the decoding units 2054-1 to 2054-U make a hard decision on the LLR sequence after decoding when the number of repetitions of SIC processing or turbo equalization reaches a predetermined number. Then, the presence / absence of an error bit is determined by cyclic redundancy check (CRC: “Cyclic Redundancy” Check), and information on the presence / absence of an error bit is output to the radio resource control unit 210.

Here, according to the present invention, interference to be removed by SIC or turbo equalization is not limited to ISI (Inter-Symbol Interference) generated by single carrier transmission, but other interference such as IUI (Inter-User Interference) may be removed. good. Further, the interference canceller is not limited to CWIC (Codeword Interference Cancellation) using the result of error correction decoding, and SLIC (Symbol level Interference Cancellation) using the demodulation result without performing error correction decoding may be used. Alternatively, a parallel interference canceller (PIC: Parallel Interference Canceller) or maximum likelihood detection (MLD: Maximum Likelihood Detection) may be used.

In this embodiment, the information of the search space for notifying the frequency resource allocation as information on the frequency resource allocation for the low delay transmission to the terminal device that requires the low delay uplink transmission in S220 of FIG. To be notified. First, in the case where the terminal apparatus performs communication using only one component carrier, it is necessary to perform 44 blind decodings. In the case of PDCCH, there are 16 candidates for USS blind decoding as shown in FIG. 9, and further decoding is possible with two types of payload sizes, DCI format 0 / 1A and DCI format according to the transmission mode. Necessary and perform 32 times of decoding. Further, there are six candidates for performing CSS blind decoding, and decoding is required with two types of payload sizes of DCI formats 0 / 1A and 1C, and decoding is performed 12 times. In addition, when UL MIMO is set, DCI format 4 is added to the payload size decoded by USS, so there are 3 types, so 48 decoding is required by USS, and 60 times blind decoding is combined with CSS. Need to do.

Therefore, the terminal apparatus performs blind decoding at least 44 times on the signal sequence received in subframe k, and when UL Grant is detected, the transmission signal generated with the transmission parameters included in UL Grant is sub-subjected to 4 Transmit after frame. In order to perform low-delay transmission with d <4 in FIG. 5, blind decoding and generation of a transmission signal are required in a shorter time. Therefore, in the present embodiment, the base station apparatus generates control information including search space information in which UL Grant for performing low-delay transmission may be arranged in the control information generation unit 207, and the control information transmission unit 208 The control information generated in is transmitted. For example, the search space information can indicate the type of search space. For example, the search space in which UL Grant for low-delay transmission is arranged is limited to USS or limited to CSS. The control information generation unit 207 transmits the terminal device information and the search space information with low delay when the search space information with the possibility of arranging UL Grant for low delay transmission is transmitted to the terminal device. Input to the management unit 211. The low-delay transmission management unit 211 is input with information on a terminal device that transmits UL Grant and information on whether or not to perform low-delay transmission, which is input from the control information generation unit 207, and there is a terminal device that performs low-delay transmission. If so, resource information for allocating UL Grant is input to the control information allocation unit 212. When there is a terminal device that performs low-delay transmission, the control information allocating unit 212 allocates UL Grant to any resource in the search space that may place the UL Grant notified to the terminal device. Here, information on whether or not the terminal apparatus performs low-delay transmission may be notified by the control information together with the SR from the terminal apparatus, or whenever control information for low-delay transmission is notified to the terminal apparatus. Low-delay transmission may be used.

On the other hand, when the terminal device receives information on a search space that may place a UL Grant for performing low-delay transmission in the control information detection unit 108, the terminal device inputs the information to the control information storage unit 109. The control information storage unit 109 holds search space information that is preferentially subjected to blind decoding, and inputs information to the control information detection unit 108 when performing blind decoding. This is because it is possible to detect a UL Grant for low-delay transmission with a small number of times of blind decoding by designating a search space where the terminal device preferentially performs blind decoding. For example, if the search space in which UL Grant for low delay transmission is arranged is limited to CSS, UL Grant for at least low delay transmission can be detected by a maximum of 12 blind decoding. However, when there is a possibility that DL Grant including frequency resource allocation for downlink transmission is transmitted at the same time, the total number of times of blind decoding is the same as the conventional one. Therefore, the terminal device can realize data transmission with a short period from reception of UL Grant to data transmission by blind-decoding the search space in which UL Grant of low-delay transmission is preferentially arranged in control information detection section 108. . Here, the arrangement of DL Grant may be limited so that the base station apparatus has the same number of times of blind decoding as UL Grant. In this way, it is possible to limit the number of times of blind decoding regardless of whether it is UL or DL. As a result, low-delay transmission is possible even in the DL, and the power consumption of the terminal device can be suppressed by reducing blind decoding. Note that the terminal device may be notified that the number of times of blind decoding is limited by RRC or the like. In addition, when the transmission mode of low delay transmission is set, UL Grant may be detected with the above-mentioned small number of times of blind decoding, and DL Grant may not be detected. In this case, the number of times of blind decoding can be suppressed, and the power consumption of the terminal device can be suppressed simultaneously with the low delay transmission. In addition, when the transmission mode of low delay transmission is set, it is possible to detect UL Grant with the above-mentioned small number of blind decoding operations without detecting DL Grant in some subframes. For example, UL Grant may be detected with a small number of times of blind decoding in 10 subframes or 20 slots, and a subframe or slot in which DL Grant is not detected may be notified to the terminal device by RRC or the like.

In the present embodiment, an example in which the search space type is notified as information on frequency resource allocation for low-delay transmission has been described, but it may be changed depending on which search space is PDCCH or EPDCCH. For example, one of the search spaces of CSS and USS of PDCCH and USS of EPDCCH may be specified. Furthermore, there is a search space in which a low delay transmission UL Grant can be arranged in EPDCCH. May be specified. In addition to the PDCCH and the EPDCCH, a search space in which a UL Grant for low delay transmission can be arranged may be defined, and this search space may be designated.

In the present embodiment, the example in which the search space type is notified as information on frequency resource allocation for low-delay transmission has been described, but the payload size may also be limited. For example, if the search space where UL Grant for low-delay transmission is placed is limited to CSS, only the payload size of DCI format 0 used for UL Grant or the payload size of DCI format 1C for low-delay transmission And so on. In this case, if the search space and the payload size are limited, the number of times of bride decoding can be reduced. For example, if the payload size is one in CSS, only six times of bride decoding is required.

As described above, in this embodiment, it is possible to detect a UL Grant for low-delay transmission with a small number of times of blind decoding, and it is possible to realize from a UL Grant reception to data transmission in a shorter period. As a result, it is possible to reduce the overhead required for data transmission from the subframe in which the terminal apparatus detects control information including frequency resource allocation for uplink transmission.

(Second Embodiment)
In the previous embodiment, the example in which the search space type is notified as information on frequency resource allocation for low-delay transmission has been described. However, in this embodiment, an example in which an aggregation level is used as information on frequency resource allocation for low-delay transmission. explain. First, the example of a structure of the terminal device in this embodiment is the same as that of previous embodiment, and is FIG. Also, the configuration example of the base station apparatus in the present embodiment is the same as that in the previous embodiment, and is shown in FIGS. Therefore, in the present embodiment, only different processing will be described, and description of similar processing will be omitted.

In this embodiment, in S220 of FIG. 5, the base station apparatus performs frequency resource allocation as information regarding frequency resource allocation for low-delay transmission to a terminal apparatus that requires low-delay uplink transmission in the control information generation unit 207. Notify the aggregation level information to be notified. Here, the aggregation level means the number of frequency resources used for the control information, and the higher the aggregation level, the more frequency resources are used, so that the control information can be transmitted at a low coding rate.

Control information including aggregation level information that may arrange UL Grant for performing low-delay transmission is generated, and the control information generated by the control information transmitting unit 208 is transmitted. For example, the information of the aggregation level is 4 or 8 defined by CSS in FIG. 9, 1 or 2, 4, 8, etc. defined by USS. If the aggregation level in which the UL Grant for performing low-delay transmission transmitted by the control information transmitting unit 208 is limited to 4, the aggregation level of CSS and USS is specified as 4. The control information generation unit 207 transmits the terminal device information and the aggregation level information with low delay transmission when the aggregation level information that may arrange UL Grant for performing low delay transmission is transmitted to the terminal device. Input to the management unit 211. The low-delay transmission management unit 211 is input with information on a terminal device that transmits UL Grant and information on whether or not to perform low-delay transmission, which is input from the control information generation unit 207, and there is a terminal device that performs low-delay transmission. If so, resource information for allocating UL Grant is input to the control information allocation unit 212. When there is a terminal device that performs low-delay transmission, the control information assignment unit 212 assigns UL Grant to any resource at an aggregation level that may place UL Grant notified to the terminal device. Here, information on whether or not the terminal apparatus performs low-delay transmission may be notified by the control information together with the SR from the terminal apparatus, or whenever control information for low-delay transmission is notified to the terminal apparatus. Low-delay transmission may be used.

On the other hand, if the terminal device receives aggregation level information that may place a UL Grant for low-delay transmission in the control information detection unit 108, the terminal device inputs the information to the control information storage unit 109. The control information storage unit 109 holds information on the aggregation level that is preferentially subjected to blind decoding, and inputs the information to the control information detection unit 108 when performing blind decoding. This is because UL Grant for low-delay transmission can be detected with a small number of times of blind decoding by designating an aggregation level at which the terminal device performs blind decoding with priority. For example, if the aggregation level in which UL Grant for low-delay transmission is arranged is limited to 4, UL Grant for at least low-delay transmission can be detected with a maximum of 12 blind decoding. However, when there is a possibility that DL Grant including frequency resource allocation for downlink transmission is transmitted at the same time, the total number of times of blind decoding is the same as the conventional one. Therefore, the terminal device can realize data transmission with a short period from reception of UL Grant to data transmission by blind-decoding the aggregation level in which UL Grant of low-delay transmission is preferentially arranged in control information detection section 108. . Also in the present embodiment, the total number of blind decoding can be reduced by limiting the aggregation level of the search space where the DL Grant may be arranged.

In the present embodiment, the example in which the aggregation level is notified as information on frequency resource allocation for low-delay transmission has been described, but the information may be changed depending on whether the search space is PDCCH or EPDCCH in addition to the aggregation level. For example, one of the search spaces of CSS and USS of PDCCH and USS of EPDCCH may be specified. Furthermore, there is a search space in which a low delay transmission UL Grant can be arranged in EPDCCH. May be specified. In addition to the PDCCH and the EPDCCH, a search space in which a UL Grant for low delay transmission can be arranged may be defined, and this search space may be designated.

In the present embodiment, the example in which the aggregation level is notified as information on frequency resource allocation for low-delay transmission has been described, but the payload size may also be limited. For example, when the aggregation level for arranging UL Grant for low-delay transmission is limited to 4, it is necessary to try signal detection by blind decoding of two payload sizes in CSS and USS, but for low-delay transmission For example, the DCI format is only one payload size. In this case, if the aggregation level and the payload size are limited, the number of times of bride decoding can be reduced. For example, if the aggregation level is 4 and the payload size is one each for CSS and USS, only 6 times of bride decoding is performed. Good.

As described above, in this embodiment, it is possible to detect a UL Grant for low-delay transmission with a small number of times of blind decoding, and it is possible to realize from a UL Grant reception to data transmission in a shorter period. As a result, it is possible to reduce the overhead required for data transmission from the subframe in which the terminal apparatus detects control information including frequency resource allocation for uplink transmission.

(Third embodiment)
In the first and second embodiments, an example has been described in which the search space type and the aggregation level are notified as information on frequency resource allocation for low-delay transmission on the premise of a terminal device to which CA is not applied. An example of a terminal device to which is applied will be described. First, the example of a structure of the terminal device in this embodiment is the same as that of previous embodiment, and is FIG. Also, the configuration example of the base station apparatus in the present embodiment is the same as that in the previous embodiment, and is shown in FIGS. Therefore, in the present embodiment, only different processing will be described, and description of similar processing will be omitted.

In this embodiment, in S220 of FIG. 5, the base station apparatus performs frequency resource allocation as information regarding frequency resource allocation for low-delay transmission to a terminal apparatus that requires low-delay uplink transmission in the control information generation unit 207. The search space to be notified, the aggregation level, and the component carrier (serving cell) information are notified. Here, when applying CA, there are a primary cell (hereinafter referred to as PCell) and a secondary cell (hereinafter referred to as SCell) in the connected component carriers. SCell differs from PCell in that PUCCH transmission is not possible. When Dual Connectivity is applied in addition to CA, each connected component carrier is either MCG (Master Cell Group) or SCG (Secondary Cell Group), and the PCCell of MCG and PSCell (Primary Cell Secondary Cell) of SCG ) PUCCH transmission is possible.

Control information including information on a component carrier that may arrange UL Grant for low-delay transmission is generated, and the control information generated by the control information transmission unit 208 is transmitted. For example, the component carrier information includes PCell, SCell, PSCell, and the like. In addition to the component carrier type, the component carrier information may include a search space type, an aggregation level, a payload size, and the like as in the previous embodiment. The control information generation unit 207 transmits the terminal device information and the component carrier information with low delay when the component carrier information with the possibility of arranging UL Grant for low delay transmission is transmitted to the terminal device. Input to the management unit 211. The low-delay transmission management unit 211 is input with information on a terminal device that transmits UL Grant and information on whether or not to perform low-delay transmission, which is input from the control information generation unit 207, and there is a terminal device that performs low-delay transmission. If so, resource information for allocating UL Grant is input to the control information allocation unit 212. When there is a terminal device that performs low-delay transmission, the control information allocating unit 212 allocates UL Grant to any resource of a component carrier that may place UL Grant notified to the terminal device. Here, information on whether or not the terminal apparatus performs low-delay transmission may be notified by the control information together with the SR from the terminal apparatus, or whenever control information for low-delay transmission is notified to the terminal apparatus. Low-delay transmission may be used. Here, if the terminal device is a component carrier that cannot transmit PUCCH, the terminal device transmits SR using PCell or PSCell.

On the other hand, if the terminal device receives information on a component carrier that may arrange UL Grant for performing low-delay transmission in the control information detection unit 108, the terminal device inputs the information to the control information storage unit 109. The control information storage unit 109 holds information of component carriers to be subjected to blind decoding with priority, and inputs the information to the control information detection unit 108 when performing blind decoding. This is because it is possible to detect the UL Grant for low-delay transmission with a small number of times of blind decoding by designating the component carrier to which the terminal device performs blind decoding with priority. This means that the terminal device needs to perform blind decoding for each CC in a timely manner. Therefore, when it is necessary to perform 44 times of blind decoding in each CC, a terminal device connected to L component carriers will perform 44 × L times of blind decoding, and more blind decoding is required. It is.

Therefore, if the component carrier, search space, and aggregation level for UL Grant for low-delay transmission are limited, the number of blind decoding required to detect UL Grant for low-delay transmission is very small. Get better. For example, when limited to CSS aggregation level 4 of one component carrier and further limited to one payload size, UL Grant for at least low-delay transmission can be detected with a maximum of 4 blind decodings. . However, when there is a possibility that DL Grant including frequency resource allocation for downlink transmission is transmitted at the same time, the total number of times of blind decoding is the same as the conventional one. Therefore, the terminal device can realize data transmission with a short period from reception of UL Grant to data transmission by blind-decoding the component carrier in which UL Grant of low-delay transmission is preferentially arranged in control information detection section 108. .

As described above, in this embodiment, it is possible to detect a UL Grant for low-delay transmission with a small number of times of blind decoding, and it is possible to realize from a UL Grant reception to data transmission in a shorter period. As a result, it is possible to reduce the overhead required for data transmission from the subframe in which the terminal apparatus detects control information including frequency resource allocation for uplink transmission.

(Fourth embodiment)
In the first to third embodiments, the example in which the terminal apparatus receives the UL Grant after transmitting the SR and performs low delay transmission has been described. However, in this embodiment, low delay transmission is performed without performing blind decoding. An example will be described. First, the configuration example of the terminal device in the present embodiment is shown in FIGS. Also, the configuration example of the base station apparatus in the present embodiment is shown in FIGS. Therefore, in the present embodiment, only different processing will be described, and description of similar processing will be omitted.

The example of the schematic diagram of the communication system of this embodiment is also FIG. 1 like the previous embodiment, and in this embodiment, the UE 21 and the eNB 10 will be described as communicating as an example. The UE 21 can transmit low-delay scheduling information (SR for low-delay transmission transmitted by the terminal device, hereinafter also referred to as low-delay scheduling information). When UE 21 generates a data signal using the resource indicated in the resource allocation information notified from eNB 10 (also referred to as a first transmission method) and UE 21 generates a data signal addressed to eNB 10, UE 21 A method of performing data transmission using the determined resource (also referred to as a second transmission method) is provided.

The resource for which the first transmission method is used (also referred to as the first resource) and the resource for which the second transmission method is used (also referred to as the second resource) can be different or the same. Or only some of the resources can be the same. The first resource can include PUCCH, PUSCH, and the like.

The UE 21 can transmit the low delay scheduling information using the first transmission method or the second transmission method. The low-latency scheduling information is information relating to a resource allocation request used by the UE 21 for data signal transmission (also referred to as resource request information), and is used (or used or determined to be used) by the UE 21 for data signal transmission. Either or both of information indicating resources (also referred to as resource notification information) can be included. The resource request information is information notified to the eNB 10 by the UE 21 to use the first transmission method, and the resource notification information is notified to the eNB 10 when (or after) the UE 21 uses the second transmission method. Information.

That is, the UE 21 can transmit a data signal, resource request information, and resource notification information at the same time. Simultaneous transmission does not necessarily mean that transmission is performed in the same resource. For example, there is no response from the eNB 10 while transmitting a data signal, resource request information, and resource notification information. You may do it. That is, the data signal, the resource request information, and the resource notification information do not necessarily have to be transmitted using the same time or the same frequency resource, and the UE 21 transmits the data signal, the resource request information, and the resource notification information. Each can be transmitted at a different time (or subframe), or can be transmitted with different frequency resources (or subcarriers, CCs, resource blocks, etc.).

By using the second transmission method, data transmission is realized without performing blind decoding for acquiring resource allocation information transmitted by the eNB 10, so that the UE 21 realizes data signal transmission with low delay. Can do. However, in the second transmission method, when there are a plurality of UEs in the communication system, the plurality of UEs may select the same resource and transmit a data signal (hereinafter also referred to as a collision). Below, the method of performing communication suitably when a collision occurs is disclosed.

The UE 21 transmits a data signal using the second transmission method (may be the first transmission method), and transmits the resource request information using the first transmission method or the second transmission method. The eNB 10 receives the data signal transmitted from the UE 21 and the resource request information. At this time, for example, the UE 21 can also transmit the resource notification information using the first transmission method or the second transmission method. For example, the eNB 10 can also receive a data signal based on the received resource notification information. At this time, it is assumed that UE 21 and UE 22 select the same resource and use the second transmission method (collision occurs). That is, the eNB 10 cannot correctly receive the data signal transmitted by the UE 21. In this case, eNB10 transmits NACK toward UE21. However, there is a problem that collision occurs when the UE 21 further transmits using the second communication method only by transmitting the NACK. Then, eNB10 can transmit resource allocation information toward UE21 based on the resource request information which UE21 transmits. The UE 21 can perform data transmission using the first transmission method based on the resource allocation information.

The UE 21 transmits the data signal using the second transmission method, and further transmits the resource request information using the first transmission method or the second transmission method. Can be expected, and thus collisions can be avoided.

The eNB 10 can perform resource allocation for the UE 21 and transmit the resource allocation information to the UE 21 regardless of the presence / absence of the resource request information of the UE 21.

FIG. 10 shows an example of a sequence chart of uplink transmission in the present embodiment. This figure shows a case where the terminal device performs low-delay transmission. In addition to the upper layer control information (for example, RRC signaling) transmitted in S100 of FIG. 4, the base station apparatus transmits information on frequency resource allocation in uplink transmission to be notified in advance as information for low delay transmission. (S300). Here, the information related to frequency resource allocation in uplink transmission notified in advance in the present embodiment includes information on SR resources for low-delay transmission and resources for data transmission. When the terminal device generates data for uplink transmission and has not received UL Grant, the terminal device arranges the SR and the data in the resources allocated for low-delay transmission notified from the base station device, respectively, and subframe k (S301). When the base station apparatus detects the low-delay transmission SR transmitted by the terminal apparatus, the base station apparatus detects the data as having been transmitted within the same subframe, and determines whether the detected data has an error. The indicated ACK / NACK is transmitted in subframe k + h (S302). However, this is a case of transmission with lower delay than in the prior art, and h ≦ 4.

In this embodiment, the example in which the SR for low delay transmission and the data signal are transmitted in the same subframe has been described. However, the data signal may be transmitted after the SR for low delay transmission is transmitted. The data signal may be transmitted before the SR for delay transmission is transmitted. For example, the terminal apparatus may transmit SR for low-delay transmission in subframe k, transmit a data signal in subframe k + d, or transmit a data signal in subframe kd. Here, the difference from FIG. 4 and FIG. 5 is that detection processing of UL Grant, that is, blind decoding is not required.

The base station apparatus generates control information including SR and data signal allocation information for low-delay transmission to a terminal apparatus that performs low-delay transmission, and transmits the control information generated in the control information transmission unit 208. The SR for low-delay transmission may be assigned a resource (frequency resource, time, sequence) different from that of the non-low-delay transmission that can be transmitted on the PUCCH, or may be transmitted using the PUSCH resource. Also, a resource block that transmits an SR for low-delay transmission may be specified.

The low delay scheduling information can be transmitted on the PUCCH or on the PUSCH. For example, the low delay scheduling information can be included in the data signal. That is, for example, the terminal device according to the present embodiment can simultaneously transmit both the data signal and the low-delay scheduling information using the data transmission resource. Further, the data signal and the scheduling information can constitute one resource block (or transport block).

FIG. 11 shows an example of the configuration of the base station apparatus according to this embodiment. When transmitting the low delay transmission SR and the data signal resource to the terminal device, the control information generation unit 207 inputs the terminal device information and the resource information to the low delay transmission management unit 311. The low delay transmission management unit 311 inputs the SR resource for low delay transmission to the control information detection unit 3044 at the reception timing of the SR for low delay transmission.

FIG. 12 shows an example of the configuration of the signal separation unit 204 according to the present invention. The control information detection unit 3044 performs SR reception processing for low-delay transmission, and, when detecting SR for low-delay transmission, inputs resource information of the data signal for low-delay transmission to the allocation signal extraction unit 3043. . The allocation signal extraction unit 3043 extracts a data signal from the resource of the data signal for low delay transmission. Subsequent signal detection processing is the same as that in the previous embodiment, and thus description thereof is omitted.

FIG. 13 shows an example of the configuration of the terminal device according to the present embodiment. When the control information detection unit 108 receives control information including low delay transmission SR and data signal allocation information, the terminal device inputs the control information to the control information storage unit 409. The control information storage unit 409 holds SR and data signal allocation information for low delay transmission, and inputs the held information to the transmission signal generation unit 101 when data requiring low delay transmission occurs. To do.

FIG. 14 shows an example of the configuration of the transmission signal generation unit 101 according to the present invention. The control signal generation unit 4018 receives SR resource information for low-delay transmission when data requiring low-delay transmission is generated, and generates an SR for low-delay transmission. In addition, when data that requires low-delay transmission occurs, the transmission signal allocation unit 4014 allocates a data signal based on the notified allocation information used for low-delay transmission. The control signal multiplexing unit 4017 multiplexes the data signal and the control information generated based on the low delay transmission SR and the data signal allocation information input from the control information storage unit 409. As described above, since there is no period until the terminal device receives UL Grant, data generation to data transmission can be shortened.

In the present embodiment, an example in which the low-delay transmission SR is transmitted once has been described, but the terminal apparatus may transmit a plurality of low-delay transmission SRs to improve the detection rate.

As described above, in this embodiment, it is possible to eliminate the overhead until the terminal device detects UL Grant from data generation to data transmission. As a result, the terminal device can reduce the overhead required for data transmission.

The program that operates in the base station apparatus and terminal apparatus related to the present invention is a program that controls the CPU or the like (a program that causes a computer to function) so as to realize the functions of the above-described embodiments related to the present invention. Information handled by these devices is temporarily stored in the RAM at the time of processing, then stored in various ROMs and HDDs, read out by the CPU, and corrected and written as necessary. As a recording medium for storing the program, a semiconductor medium (for example, ROM, nonvolatile memory card, etc.), an optical recording medium (for example, DVD, MO, MD, CD, BD, etc.), a magnetic recording medium (for example, magnetic tape, Any of a flexible disk etc. may be sufficient. In addition, by executing the loaded program, not only the functions of the above-described embodiment are realized, but also based on the instructions of the program, the processing is performed in cooperation with the operating system or other application programs. The functions of the invention may be realized.

In addition, when distributing to the market, the program can be stored in a portable recording medium for distribution, or transferred to a server computer connected via a network such as the Internet. In this case, the storage device of the server computer is also included in the present invention. Further, part or all of the base station apparatus and terminal apparatus in the above-described embodiment may be realized as an LSI that is typically an integrated circuit. Each functional block of the base station apparatus and the terminal apparatus may be individually chipped, or a part or all of them may be integrated into a chip. Further, the method of circuit integration is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. When each functional block is integrated, an integrated circuit controller for controlling them is added.

Further, the method of circuit integration is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. In addition, when an integrated circuit technology that replaces LSI appears due to progress in semiconductor technology, an integrated circuit based on the technology can also be used.

Further, the present invention is not limited to the above-described embodiment. The terminal device of the present invention is not limited to application to a mobile station device, but is a stationary or non-movable electronic device installed indoors or outdoors, such as AV equipment, kitchen equipment, cleaning / washing equipment Needless to say, it can be applied to air conditioning equipment, office equipment, vending machines, and other daily life equipment.

As described above, the embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes design changes and the like without departing from the gist of the present invention. The present invention can be modified in various ways within the scope of the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments are also included in the technical scope of the present invention. It is. Moreover, it is the element described in each said embodiment, and the structure which substituted the element which has the same effect is also contained.

This international application claims priority based on Japanese Patent Application No. 2015-098649 filed on May 14, 2015. The entire contents of Japanese Patent Application No. 2015-098649 are hereby incorporated by reference. Included in international applications.

DESCRIPTION OF SYMBOLS 10 ... Base station apparatus 21-25 ... Terminal device 101 ... Transmission signal generation part 102 ... IFFT part 103 ... Transmission power control part 104 ... Transmission processing part 105 ... Transmission antenna 106 ... Reception antenna 107 ... Radio reception part 108 ... Control information detection Unit 109 ... control information storage unit 1011 ... error correction encoding unit 1012 ... modulation unit 1013 ... DFT unit 1014 ... transmission signal allocation unit 1015 ... reference signal multiplexing unit 1016 ... reference signal generation unit 1017 ... control information multiplexing unit 1018 ... control signal Generation unit 201: reception antenna 202 ... reception processing unit 203 ... FFT unit 204 ... signal separation unit 205 ... signal detection unit 206 ... propagation path estimation unit 207 ... control information generation unit 208 ... control information transmission unit 209 ... transmission antenna 210 ... wireless Resource control unit 211 ... low delay transmission management unit 212 ... control information allocation unit 2 041 ... Reference signal separation unit 2042 ... Control information separation unit 2043 ... Allocation signal extraction unit 2044 ... Control information detection unit 2051 ... Equalization unit 2052-1 to 2052-U ... IDFT unit 2053-1 to 2053-U ... Demodulation unit 2054 -1 to 2054-U: decoding unit 311: low delay transmission management unit 3043 ... allocation signal extraction unit 3044 ... control information detection unit 409 ... control information storage unit 4014 ... transmission signal allocation unit 4017 ... control signal multiplexing unit 4018 ... control signal Generator

Claims (8)

A base station device that receives a data signal transmitted from a terminal device,
A low-delay transmission manager that holds information on which of the first data transmission in which the terminal device performs low-delay data transmission and the second data transmission in which the terminal device performs non-low-delay data transmission; A control signal generator for generating first control information including information related to resource allocation used at the time of data transmission, and control information allocation for allocating second control information including a transmission parameter used for data transmission by the terminal device to the resource And
The base station apparatus, wherein the control information allocation unit allocates the control information based on information on the resource allocation included in the first control information when transmitting the first data. The base station apparatus according to claim 1, wherein the information related to resource allocation included in the first control information is information specifying a search space. The base station apparatus according to claim 1, wherein the information on the resource allocation included in the first control information is information specifying PDCCH or EPDCCH. The base station apparatus according to claim 1, wherein the information on the resource allocation included in the first control information is information specifying an aggregation level. The base station apparatus according to claim 1, wherein the information on the resource allocation included in the first control information is information specifying a payload size. The base station apparatus according to claim 1, wherein the information related to resource allocation included in the first control information is information specifying a component carrier. A terminal device that transmits a data signal to a base station device,
Notified by the first control information and the transmission processing unit that transmits data in either the first data transmission that performs low-delay data transmission or the second data transmission in which the terminal device performs data transmission that is not low-delay A control information storage unit that holds information relating to resource allocation used at the time of the first data transmission, and second control information that includes a transmission parameter used in either the first data transmission or the second data transmission is detected. A control information detection unit
The terminal characterized in that the control information detection unit preferentially detects the resource notified by the first control information among resources in which the second control information may be arranged. apparatus. The information related to resource allocation used when transmitting the first data notified by the first control information includes information specifying a search space, information specifying a PDCCH or EPDCCH, information specifying an aggregation level, and a payload size. The terminal device according to claim 7, comprising at least one of information for designating and information for designating a component carrier.

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