JP2011142494A - Base station device, mobile station device, radio communication system, control program of base station device, integrated circuit, and communication method of base station device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To more flexibly allocate a frequency band for transmitting an uplink signal from a base station device to a mobile station device without causing the deterioration of throughput, and on the other hand, to reduce the amount of information needed for resource allocation. <P>SOLUTION: The base station device 1 which allocates the frequency band for the mobile station device to transmit data by an uplink, and notifies the mobile station device of the allocation information of the frequency band is provided with: a scheduling part 120 which divides a predetermined frequency band into a plurality of continuous groups, specifies a group including the frequency band allocated to the mobile station device, and generates the band allocation information including information showing the start position and the end position of the frequency band allocated to the mobile station device in the group; and a transmitting part 110 which transmits the generated band allocation information to the mobile station device. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention is applied to a radio communication system including a base station device and a mobile station device, and the base station device allocates a frequency band for transmitting data in the uplink to the mobile station device, and the frequency The present invention relates to a technique for notifying mobile station apparatus of bandwidth allocation information.

  Currently, 3rd Generation Partnership Project (3GPP) has developed LTE Advanced (hereinafter referred to as “LTE”) for the evolution of 3rd generation wireless access technology (Long Term Evolution: hereinafter referred to as “LTE”) and further increase in communication speed. -A ") is also being studied. In LTE, SC-FDMA (Single Carrier Frequency Division Multiple Access) is supported, and only a continuous area on the frequency axis can be allocated to one mobile station apparatus. In LTE-A, an uplink data signal ( By using clustered DFT-S-OFDM (Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing) as an access method in UL-SCH (Uplink Shared Channel) transmission, it becomes possible to assign non-contiguous frequency regions.

  Here, a group of continuous frequency bands is referred to as a cluster. On the other hand, the uplink frequency band allocated by the base station apparatus is notified to each mobile station apparatus via a downlink control channel (PDCCH: Physical Downlink Control Channel), but clustered DFT-S-OFDM (Discrete Fourier). Non-contiguous frequency domain allocation by Transform Spread Orthogonal Frequency Division Multiplexing is not supported in LTE.

  While LTE does not support transmission of uplink signals by MIMO, LTE-A is considering to support MIMO, and not only coding rate and modulation scheme applied to UL-SCH, but also spatial multiplexing. The number (rank) and the preprocessing sequence (precoder) are also calculated using a channel calculation reference signal (sounding reference signal, SRS) transmitted from the mobile station apparatus to the base station apparatus. Since an optimal precoder calculation error due to noise or the like causes a reduction in throughput in LTE-A, LTE-A must realize SRS transmission with higher accuracy than LTE. As one means for realizing this, there is a method for improving the SNR (Signal to Noise Ratio) by concentrating the transmission power in a certain bandwidth by setting the bandwidth for transmitting the SRS to be narrower than the system bandwidth. .

  On the other hand, for a method of notifying an allocated frequency band (hereinafter referred to as resource allocation) corresponding to discrete arrangement in the frequency domain by clustered DFT-S-OFDM, the method as described in Non-Patent Documents 1 to 4. Has been proposed. Non-Patent Document 1 proposes that resource allocation is shown with the same bit size as SC-FDMA when the number of clusters supported by clustered DFT-S-OFDM is limited to two. Non-Patent Document 2 proposes realizing resource allocation by indicating the start and end positions of the first and second clusters when the number of clusters supported by clustered DFT-S-OFDM is limited to two. is doing.

R1-094573 “Control Signaling for Non-Contiguous UL Resource Allocations”, Samsung, 3GPP TSG RAN WG1, Jeju, Korea, November, 2009 R1-094703 “Views on PUSCH Resource allocation”, Huawei, 3GPP TSG RAN WG1, Jeju, Korea, November, 2009

  However, the method of Non-Patent Document 1 is a resource allocation on the premise that the number of clusters is limited to two, and there is no extensibility when the number of clusters is three or more. Therefore, a resource allocation technique that can be applied even when the number of clusters is three or more is desired.

  The present invention has been made in view of such circumstances, and while allocating a frequency band for transmitting an uplink signal more flexibly from a base station apparatus to a mobile station apparatus without causing a decrease in throughput, resource allocation An object of the present invention is to provide a base station device, a mobile station device, a wireless communication system, a control program for the base station device, an integrated circuit, and a communication method for the base station device that can reduce the amount of information required for the communication.

  (1) In order to achieve the above object, the present invention takes the following measures. That is, the base station apparatus of the present invention is a base station apparatus that allocates a frequency band for the mobile station apparatus to transmit data in the uplink and notifies the mobile station apparatus of frequency band allocation information, A predetermined frequency band is divided into a plurality of continuous groups, a group including the frequency band allocated to the mobile station apparatus is specified, and a start position and an end position of the frequency band allocated to the mobile station apparatus in the group And a base station side transmitting unit for transmitting the generated band allocation information to the mobile station apparatus.

  Thus, the predetermined frequency band is divided into a plurality of continuous groups, the group including the frequency band allocated to the mobile station apparatus is specified, and the frequency band allocated to the mobile station apparatus within the group is specified. Since band allocation information including information indicating the start position and end position is generated, it is possible to limit frequency band allocation and move the frequency band for transmitting uplink signals flexibly from the base station apparatus. It becomes possible to assign to a station apparatus. As a result, it is possible to reduce the number of bits required when notifying the bandwidth allocation information and avoid a decrease in throughput.

  (2) Further, in the base station apparatus of the present invention, the scheduling unit causes the mobile station apparatus to transmit an uplink data signal by a clustered DFT-S-OFDM (Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing) scheme. Generating the bandwidth allocation information.

  As described above, since the mobile station apparatus generates the band allocation information so that the uplink data signal is transmitted by the clustered DFT-S-OFDM scheme, the communication using the clustered DFT-S-OFDM scheme is realized. Is possible. In the clustered DFT-S-OFDM, the PAPR increases as the number of divisions (number of clusters) increases. Therefore, it is desirable to perform scheduling such that the number of divisions is increased based on the frequency band availability based on the number of clusters 1. . The idea of dividing a predetermined frequency band into a plurality of continuous groups is suitable for clustered DFT-S-OFDM.

  (3) Further, in the base station apparatus of the present invention, the predetermined frequency band may be an entire band that can be used for transmission of PUSCH (Physical Uplink Shared Channel) or an SRS (Sounding Reference Signal) transmitted by the mobile station apparatus. The transmission frequency band is any one of the following.

  Thus, the predetermined frequency band is either the entire band that can be used for transmission of PUSCH (Physical Uplink Shared Channel) or the transmission frequency band of SRS (Sounding Reference Signal) transmitted by the mobile station apparatus. Therefore, when the predetermined frequency band is the entire band that can be used for PUSCH transmission, the signal frequency is exchanged between the base station apparatus and the mobile station apparatus by fixing the target frequency band. Can be reduced. Further, the frequency band scheduled by the base station apparatus is desirably a frequency band in which SRS is transmitted, that is, a frequency band in which propagation path information is known. When the predetermined frequency band is a transmission frequency band of SRS, more suitable scheduling is possible by determining the frequency band according to the frequency band in which the SRS is transmitted.

  (4) Moreover, the base station apparatus of this invention notifies the information which shows either the said system band or the transmission frequency band of the said SRS with respect to the said mobile station apparatus, It is characterized by the above-mentioned.

  As described above, since the mobile station apparatus is notified of information indicating either the system band or the SRS transmission frequency band, the mobile station apparatus allocates the resource of either the system band or the SRS transmission frequency band. By using it, it becomes possible to transmit an uplink data signal. When the notified frequency band is the system band, signal exchange between the base station apparatus and the mobile station apparatus can be reduced by fixing the target frequency band. Further, when the notified frequency band is an SRS transmission frequency band, more appropriate scheduling is possible by determining the frequency band in accordance with the frequency band in which the SRS is transmitted.

  (5) Moreover, the base station apparatus of this invention notifies the division | segmentation number at the time of dividing | segmenting the said predetermined frequency band into a some group with respect to the said mobile station apparatus.

  As described above, since the mobile station device is notified of the number of divisions when the predetermined frequency band is divided into a plurality of groups, the mobile station device grasps the number of divisions of the predetermined frequency band. be able to. The optimal number of divisions that maximizes the throughput depends on the scheduling algorithm. On the other hand, as the number of divisions increases, the bit size of the frequency band allocation information increases. Therefore, by allowing the base station apparatus to set this flexibly, it is possible to provide higher flexibility in mounting the base station apparatus.

  (6) Moreover, the mobile station apparatus of this invention is based on the allocation information of the frequency band received from the base station apparatus of said (2), Clustered DFT-S-OFDM (Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing) ) Method to transmit an uplink data signal to the base station apparatus.

  With this configuration, communication using the clustered DFT-S-OFDM scheme can be realized.

  (7) Moreover, the radio | wireless communications system of this invention is comprised from the base station apparatus as described in said (2), and the mobile station apparatus as described in said (6), It is characterized by the above-mentioned.

  With this configuration, communication using the clustered DFT-S-OFDM scheme can be realized.

  (8) Further, the control program for the base station apparatus of the present invention assigns a frequency band for the mobile station apparatus to transmit data in the uplink, and notifies the mobile station apparatus of frequency band allocation information. A device control program, a process of dividing a predetermined frequency band into a plurality of continuous groups, a group including a frequency band assigned to the mobile station device is specified, and the mobile station device within the group A series of processes including a process of generating band allocation information including information indicating a start position and an end position of a frequency band allocated to, and a process of transmitting the generated band allocation information to the mobile station apparatus. The computer is readable and executable as a command.

  Thus, the predetermined frequency band is divided into a plurality of continuous groups, the group including the frequency band allocated to the mobile station apparatus is specified, and the frequency band allocated to the mobile station apparatus within the group is specified. Since band allocation information including information indicating the start position and end position is generated, it is possible to limit frequency band allocation and move the frequency band for transmitting uplink signals flexibly from the base station apparatus. It becomes possible to assign to a station apparatus. As a result, it is possible to reduce the number of bits required when notifying the bandwidth allocation information and avoid a decrease in throughput.

  (9) Moreover, the control program of the base station apparatus of the present invention is configured so that the mobile station apparatus transmits an uplink data signal by a clustered DFT-S-OFDM (Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing) scheme. Bandwidth allocation information is generated.

  As described above, since the mobile station apparatus generates the band allocation information so that the uplink data signal is transmitted by the clustered DFT-S-OFDM scheme, the communication using the clustered DFT-S-OFDM scheme is realized. Is possible. In the clustered DFT-S-OFDM, the PAPR increases as the number of divisions (number of clusters) increases. Therefore, it is desirable to perform scheduling such that the number of divisions is increased based on the frequency band availability based on the number of clusters 1. . The idea of dividing a predetermined frequency band into a plurality of continuous groups is suitable for clustered DFT-S-OFDM.

  (10) Moreover, the integrated circuit of the present invention is an integrated circuit that causes the base station apparatus to perform a plurality of functions by being mounted on the base station apparatus, and the mobile station apparatus transmits data in the uplink. A function for allocating a frequency band for use, a function for notifying the mobile station apparatus of frequency band allocation information, a function for dividing a predetermined frequency band into a plurality of continuous groups, and a function allocated to the mobile station apparatus A function of identifying a group including a frequency band and generating band allocation information including information indicating a start position and an end position of a frequency band allocated to the mobile station apparatus in the group; and the generated band allocation information The base station apparatus is caused to exhibit a series of functions including a function of transmitting to a mobile station apparatus.

  Thus, the predetermined frequency band is divided into a plurality of continuous groups, the group including the frequency band allocated to the mobile station apparatus is specified, and the frequency band allocated to the mobile station apparatus within the group is specified. Since band allocation information including information indicating the start position and end position is generated, it is possible to limit frequency band allocation and move the frequency band for transmitting uplink signals flexibly from the base station apparatus. It becomes possible to assign to a station apparatus. As a result, it is possible to reduce the number of bits required when notifying the bandwidth allocation information and avoid a decrease in throughput.

  (11) In the integrated circuit of the present invention, the mobile station apparatus transmits the band allocation information so that an uplink data signal is transmitted by a clustered DFT-S-OFDM (Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing) method. It is characterized by generating.

  As described above, since the mobile station apparatus generates the band allocation information so that the uplink data signal is transmitted by the clustered DFT-S-OFDM scheme, the communication using the clustered DFT-S-OFDM scheme is realized. Is possible. In the clustered DFT-S-OFDM, the PAPR increases as the number of divisions (number of clusters) increases. Therefore, it is desirable to perform scheduling such that the number of divisions is increased based on the frequency band availability based on the number of clusters 1. . The idea of dividing a predetermined frequency band into a plurality of continuous groups is suitable for clustered DFT-S-OFDM.

  (12) Further, in the communication method of the base station apparatus of the present invention, the mobile station apparatus allocates a frequency band for transmitting data in the uplink, and notifies the mobile station apparatus of frequency band allocation information. A device communication method, wherein a scheduling unit divides a predetermined frequency band into a plurality of continuous groups, specifies a group including a frequency band allocated to the mobile station device, and moves the mobile unit within the group. A step of generating band allocation information including information indicating a start position and an end position of a frequency band allocated to the station apparatus, and the base station side transmitting unit transmits the generated band allocation information to the mobile station apparatus And at least a step.

  Thus, the predetermined frequency band is divided into a plurality of continuous groups, the group including the frequency band allocated to the mobile station apparatus is specified, and the frequency band allocated to the mobile station apparatus within the group is specified. Since band allocation information including information indicating the start position and end position is generated, it is possible to limit frequency band allocation and move the frequency band for transmitting uplink signals flexibly from the base station apparatus. It becomes possible to assign to a station apparatus. As a result, it is possible to reduce the number of bits required when notifying the bandwidth allocation information and avoid a decrease in throughput.

  (13) Further, in the communication method of the base station apparatus of the present invention, the scheduling unit allows the mobile station apparatus to transmit an uplink data signal by a clustered DFT-S-OFDM (Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing) scheme. The method further comprises the step of generating the band allocation information to transmit.

  As described above, since the mobile station apparatus generates the band allocation information so that the uplink data signal is transmitted by the clustered DFT-S-OFDM scheme, the communication using the clustered DFT-S-OFDM scheme is realized. Is possible. In the clustered DFT-S-OFDM, the PAPR increases as the number of divisions (number of clusters) increases. Therefore, it is desirable to perform scheduling such that the number of divisions is increased based on the frequency band availability based on the number of clusters 1. . The idea of dividing a predetermined frequency band into a plurality of continuous groups is suitable for clustered DFT-S-OFDM.

  According to the present invention, clustered DFT-S-OFDM resource allocation can be realized depending on the scheduling algorithm of the base station apparatus and depending on whether or not the propagation path information necessary for scheduling is acquired.

It is a functional block diagram which shows the example of 1 structure of the base station apparatus 1 of this invention. It is a functional block diagram which shows one structural example of the mobile station apparatus 3 of this invention. 4 is a sequence chart showing an operation of allocating a frequency band used for UL-SCH transmission by the base station apparatus 1 according to the first embodiment of the present invention to the mobile station apparatus 3. It is the figure which showed the mechanism of the resource allocation transmitted by step S103 of FIG. 3 which concerns on the 1st Embodiment of this invention (when N = 2). It is the figure which showed the mechanism of the resource allocation transmitted by step S103 of FIG. 3 which concerns on the 1st Embodiment of this invention (when N = 3). It is a sequence chart which shows the operation | movement which the base station apparatus 1 which concerns on the 2nd Embodiment of this invention allocates the frequency band utilized for transmission of UL-SCH with respect to the mobile station apparatus 3. It is the figure which showed the mechanism of the resource allocation transmitted by step S205 of FIG. 5 which concerns on the 2nd Embodiment of this invention (when N = 2). It is the figure which showed the mechanism of the resource allocation transmitted by step S205 of FIG. 5 which concerns on the 2nd Embodiment of this invention (when N = 3). It is the figure which showed concretely about the transmission method of SRS in LTE. It is the figure which showed the detailed structure of the sounding sub-frame. It is the figure shown about the transmission method of SRS. It is a figure which shows the mechanism of the resource allocation corresponding to SC-FDMA in LTE.

  As a next-generation cellular mobile communication system, 3GPP, an international standardization project, is studying network specifications that have developed W-CDMA (Wideband-Code Division Multiple Access) and GSM (Global System for Mobile Communications). It is done. In 3GPP, cellular mobile communication systems have been studied for some time, and the W-CDMA system has been standardized as a third-generation cellular mobile communication system. Also, HSDPA (High-Speed Downlink Packet Access) that further improves the communication speed has been standardized and the service is being operated. Currently, in 3GPP, the evolution of the third generation radio access technology (Long Term Evolution: hereinafter referred to as “LTE”) and LTE Advanced (hereinafter referred to as “LTE-A”) for further increase in communication speed. Is also being studied.

  In uplink data transmission in LTE, a communication scheme based on SC-FDMA (Single Carrier Frequency division multiple Access) based on resources allocated from a base station apparatus is employed. Specifically, the modulated transmission signal is converted into a frequency domain signal by DFT (Discrete Fourier Transformation), mapped to the frequency resource allocated by the base station apparatus, and then transmitted in the time domain by IDFT (Inverse DFT). It is converted into a signal and transmitted to the base station apparatus. Here, the uplink data corresponds to data that is passed from the upper layer and does not interpret the meaning of each bit in the physical layer, and is referred to as UL-SCH (Uplink Shared Channel) defined in the transport channel. . Data that is actually transmitted is obtained by performing processing such as encoding on UL-SCH, and is a data signal transmission channel called PUSCH (Physical Uplink Shared Channel) assigned to the mobile station device by the base station device. This is sent.

  As for the multi-antenna transmission technique in the LTE uplink, antenna switching for adaptively selecting one transmission antenna from two transmission antennas is supported. On the other hand, in LTE-A, application of spatial multiplexing by MIMO (Multiple Input Multiple Output) is being studied as an extension of the uplink scheme, and UL-SCH data is spatially multiplexed by a maximum of four transmission antennas. A plurality of sequences are transmitted. Here, the number of spatially multiplexed sequences applied to the UL-SCH, the coding rate, and the modulation scheme are channel calculation reference signals (sounding reference signals, SRS: Sounding Reference Signal) transmitted from the mobile station apparatus to the base station apparatus. Calculated using. In addition to this application, SRS is also used for frequency scheduling.

  FIG. 7 is a diagram specifically illustrating an SRS transmission method in LTE. The base station apparatus sets a sounding subframe between the entire mobile station apparatus that communicates with the base station apparatus. Specifically, the sounding subframe is given an offset and a period from the reference subframe. The sounding subframe is common to all mobile station apparatuses, and means that any of the mobile station apparatuses transmits a SRS to the base station apparatus in this subframe.

  FIG. 8 is a diagram illustrating a detailed configuration of the sounding subframe. However, FIG. 8 shows only a band that can be used as a PUSCH, and a frequency band for transmitting control information is omitted. The vertical axis in FIG. 8 is the frequency axis, and one block represents a subcarrier. In LTE, 12 consecutive subcarriers are collectively used as a resource allocation unit, which is called a resource block (RB). On the other hand, the horizontal axis is a time axis, in which the frequency domain is converted to the time domain, and the time is divided by a unit that gives a cyclic prefix. This is referred to as a 1SC-FDMA symbol. In LTE, one slot is composed of consecutive 7SC-FDMA symbols, and two sub-frames are composed of two slots. The subframe is a resource division unit in the time domain in LTE and LTE-A.

  As shown in FIG. 8, each SC-FDMA symbol can be used for different applications, and SC-FDMA symbol # 3 is used for transmission of a reference signal (DMRS: Demodulation RS) for data demodulation. The SC-FDMA symbol # 6 in slot # 1 is used for transmission of SRS. Other SC-FDMA symbols are used for data transmission. Here, DMRS and SRS use orthogonal codes for multiplexing with other users and antenna identification. In LTE, a CAZAC (Constant Amplitude and Zero-autocorrelation) sequence is cyclically shifted on the time axis. A sequence based on the signal sequence is used.

  FIG. 9 is a diagram illustrating an SRS transmission method. The base station apparatus performs settings related to SRS transmission in common with the mobile station apparatus or in a batch of mobile station apparatuses. Here, the setting means that the position of a subframe that can be used by the mobile station apparatus among the SRS subframes is set by the offset and the period, and the SRS bandwidth that is supported by SRS and the SRS bandwidth that is transmitted in one subframe. , And from which antenna is transmitted.

  Specifically, using FIG. 9, here, even-numbered subframes are set as SRS subframes, and {4, 8, 12, 16, 20, 24} subframes are allocated to this mobile station apparatus. ing. Here, the subframe to be transmitted is called a time position of SRS transmission. The band supported by the SRS of this mobile station apparatus is F, which is a part of the system bandwidth, and one-third of the width of the band F, that is, the bands F1, F2, and F3 are determined in advance by one SRS transmission. Sent in the order given. Here, the frequency band to be transmitted is called the frequency position of SRS transmission. In addition, it is assumed that this mobile station apparatus has two transmission antennas, and an SRS corresponding to one antenna is transmitted in one subframe. Specifically, in this example, the antennas # 0 and # 1 are set to be alternately transmitted at the respective transmission timings. 7 and 8, it is assumed that the SRS transmitted from each transmission antenna uses different subframes. However, at the same time and the same frequency, the SRS is code-multiplexed by the cyclic shift and transmitted. It is also possible to make it.

  FIG. 10 is a diagram showing a resource allocation mechanism corresponding to SC-FDMA in LTE. The horizontal axis of FIG. 10 represents frequency, and 10 RBs are designated by resource allocation. The resource allocation in LTE includes information indicating the start position and end position of the RB assigned to the mobile station apparatus. In the example of FIG. 10, the fifth RB is designated as the start position, RB is notified to the mobile station apparatus as the end position. The mobile station apparatus that has received this interprets that RBs 5, 6, 7, and 8 are allocated, and transmits UL-SCH using this frequency band. Embodiments of the present invention will be described below with reference to the drawings. Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
The mobile communication system according to the first embodiment of the present invention includes a base station device 1 and a mobile station device 3. FIG. 1 is a functional block diagram showing a configuration example of the base station apparatus 1 of the present invention. The base station apparatus 1 of the present invention includes a transmission unit 110 (base station side transmission unit), a scheduling unit 120, a reception unit 130, and an antenna 140. The transmission unit 110 includes an encoding unit 111, a modulation unit 112, a mapping unit 113, and a wireless transmission unit 114. The scheduling unit 120 includes an uplink transmission frequency band allocation unit 121, an uplink resource allocation information generation unit 122, and an SRS band control unit 123. The reception unit 130 includes a radio reception unit 131 and an SRS separation / calculation unit 132. , An inverse mapping / demodulation processing unit 133 is provided. The antennas 140 are provided as many as necessary for transmitting downlink signals and receiving uplink signals.

  The downlink data generated in the base station device 1 and transmitted to each mobile station device 3 and the scheduling information for control information transmission output from the scheduling unit 120 are input to the encoding unit 111, and each of them is scheduled. Encoding is performed according to the control signal from unit 120, and an encoded bit string is output. The control signal from the scheduling unit 120 represents information indicating a coding rate and a coding scheme such as a turbo code or a tail biting convolutional code. In addition, a plurality of pieces of information may be combined and encoded, and each piece of information may be encoded separately. Here, the information provided from the scheduling unit 120 is characterized in that it includes information relating to a band used for uplink transmission, that is, resource allocation. More specifically, it represents uplink resource allocation information (UL Grant) including resource allocation.

  A plurality of output bit strings of the encoding unit 111 are input to the modulation unit 112, and each of them is converted according to a control signal from the scheduling unit 120, for example, converted into BPSK, QPSK, 16QAM, and 64QAM symbols and output. The output of the modulation unit 112 is input to the mapping unit 113 together with the downlink scheduling information provided from the scheduling unit 120, and transmission data is generated. Here, the transmission data refers to, for example, an OFDM signal, and the mapping operation corresponds to an operation corresponding to the frequency and time resources specified for each mobile station apparatus 3. If spatial multiplexing by MIMO is employed, this processing is performed in this block. Here, the control information refers to uplink or downlink resource allocation information, that is, transmission timing and frequency resource information, uplink or downlink signal modulation scheme and coding rate, and CQI and PMI for the mobile station apparatus 3. , RI transmission request, etc.

  The signal generated by the mapping unit 113 is output to the wireless transmission unit 114. The wireless transmission unit 114 is converted into a form suitable for the transmission method, and if it is a communication method specifically conforming to OFDMA, IFFT (Inverse Fast Fourier Transformation) is performed on the signal in the frequency domain, A time domain signal is generated. An output signal of the wireless transmission unit 114 is supplied to the antenna 140 and is transmitted to each mobile station apparatus 3 from here.

  The scheduling unit 120 manages and controls the control information from the higher layer and the information transmitted from the mobile station apparatus 3, determines the resource allocation to each mobile station apparatus 3, the modulation scheme, the coding rate, and these operations. Control and output of control information are performed. Uplink transmission frequency band allocating section 121 performs UL-SCH scheduling using a signal transmitted by each mobile station apparatus 3, for example, SRS. That is, which mobile station device 3 uses which frequency band is determined. Algorithms such as MAX CIR (Carrier to Interference Ratio), PF (Proportional Fairness), and RR (Round Robin) can be applied to this determination method, but a specific method is not limited.

  The uplink resource allocation information generation unit 122 generates a resource allocation signal to be transmitted to each mobile station apparatus 3 based on the scheduling information of the uplink transmission frequency band allocation unit 121, and further supports clusters supported by the base station apparatus 1. A number N can also be determined. The SRS band control unit 123 manages SRS code resources applied to each mobile station device 3. The resource allocation information generated by the uplink resource allocation information generation unit 122 can also be determined by the maximum number of clusters selected by the base station apparatus 1 and the SRS bandwidth controlled by the SRS band control unit 123.

  On the other hand, a signal transmitted from the mobile station device 3 is received by the antenna 140 and then input to the radio reception unit 131. The wireless receiving unit 131 receives data and control signals, generates a digital signal corresponding to the transmission method, and outputs it. Specifically, if the OFDM method or the SC-FDMA method is employed, after the received signal is converted from analog to digital, a signal subjected to FFT processing in units of processing time is output. Here, the radio reception unit 131 includes a signal for measuring the state of the uplink propagation path and a signal such as a data signal processed in an upper layer and a signal including information to be managed as control information. The signals are divided into two types and output as a first signal and a second signal, respectively.

  The first output of the wireless reception unit 131 is output to the SRS separation / calculation unit 132. Here, SRS or SRS included in the uplink signal is extracted, and channel information of each mobile station apparatus 3 obtained therefrom is output to scheduling section 120. In particular, there is a possibility that the SRS is multiplexed for each user or other information depending on time, frequency, and code resources, and these are separated according to the resource allocation information managed by the SRS band control unit 123.

  The second output of the wireless reception unit 131 is output to the inverse mapping / demodulation processing unit 133. The inverse mapping / demodulation processing unit 133 demodulates and extracts a plurality of types of information transmitted from the mobile station device 3 using the mapping pattern, modulation scheme, and coding rate managed by the scheduling unit 120. Here, if spatial multiplexing is applied to the uplink signal and two or more types of information having different communication qualities are transmitted at the same time, the time and frequency position in which each signal is included are separated in advance, and scheduling is performed. According to the control information input from unit 120, inverse mapping and demodulation processing using different modulation schemes, coding rates, and spatial multiplexing numbers are performed. Among the signals obtained by such processing, those processed in the upper layer are output to the upper layer, and control information managed by the scheduling unit 120, such as CQI and RI, is sent to the scheduling unit 120. Is output.

  FIG. 2 is a functional block diagram showing a configuration example of the mobile station apparatus 3 of the present invention. As shown in FIG. 2, the mobile station device 3 includes a reception unit 210, a scheduling information management unit 220, a transmission unit 230, and an antenna 240. The reception unit 210 includes a wireless reception unit 211, a demodulation processing unit 212, and a downlink propagation path calculation unit 213. The scheduling information management unit 220 includes an uplink resource allocation information management unit 221 and an SRS bandwidth management unit 222. There are as many antennas 240 as necessary for transmitting uplink signals and receiving downlink signals. The transmission unit 230 includes an encoding unit 231, a modulation unit 232, a mapping unit 233, and a wireless transmission unit 234.

  When the downlink signal transmitted from the base station apparatus 1 is received by the antenna 240, this received signal is input to the radio reception unit 211. The wireless reception unit 211 performs processing according to the communication method in addition to analog / digital (A / D) conversion and the like, and outputs the result. Specifically, in the case of OFDMA, the time-series signal after A / D conversion is subjected to FFT processing, converted into a time / frequency domain signal, and output.

  An output signal of the wireless reception unit 211 is input to the demodulation processing unit 212. At the same time, the demodulation processor 212 has downlink signal scheduling information output from the scheduling information manager 220 (that is, information on where the signal addressed to itself is allocated), the number of spatially multiplexed sequences, the modulation method, the code Control information such as the conversion rate is also input, and demodulation processing is performed. The demodulated signals are classified according to the signal type, information processed in the upper layer is passed to the upper layer, and information managed by the scheduling information management unit 220 is input to the scheduling information management unit 220. . Here, the information managed by the scheduling information management unit 220 includes information on uplink resource allocation and information on resources (time, frequency, code resource) for transmitting SRS. The downlink propagation path calculation unit 213 uses the propagation path calculation signal provided from the radio reception unit 211 as an input signal to calculate management information such as the number of spatially multiplexed sequences, modulation scheme, and coding rate applicable to the downlink. . This management information is input to the scheduling information management unit 220.

  The scheduling information management unit 220 manages control information transmitted from the base station apparatus 1 and also performs management for transmitting control information calculated by the mobile station apparatus 3 to the base station apparatus 1. The uplink resource allocation information management unit 221 manages the uplink resource information of the own station transmitted from the base station apparatus 1. Specifically, the received resource allocation information is interpreted in consideration of the number of clusters N transmitted from the base station apparatus 1, the SRS bandwidth, and the like, and is specifically converted into a frequency band that can be used for UL-SCH transmission. translate. The SRS band management unit 222 manages code resources applied to the SRS transmitted from the base station apparatus 1 and controls SRS transmission using those resources.

  The transmission unit 230 transmits information on uplink resources to which information such as uplink data and SRS is assigned. The signals managed by the downlink data and scheduling information management unit 220 are supplied to the encoding unit 231 at the transmission timing, and the input signals are encoded at different coding rates depending on the respective types. The plurality of series of output signals are input to the modulation unit 232 and modulated by different modulation schemes depending on the type. This output is output to mapping section 233, which performs signal mapping according to the spatial multiplexing number and resource allocation for each transmission information.

  The signal mapped by the mapping unit 233 is input to the wireless transmission unit 234. The wireless transmission unit 234 converts these signals into a signal form for transmission. Specifically, an operation of converting a frequency domain signal into a time domain signal by IFFT and providing a guard interval corresponds to this. The output of the wireless transmission unit 234 is supplied to the antenna 240.

  FIG. 3 is a sequence chart showing an operation in which the base station apparatus 1 according to the first embodiment of the present invention allocates a frequency band used for UL-SCH transmission to the mobile station apparatus 3. In FIG. 3, the frequency band which is comprised from the two base station apparatuses 1 and the mobile station apparatus 3 which concern on the 1st Embodiment of this invention, and is used for transmission of UL-SCH from the base station apparatus 1 to the mobile station apparatus 3 Is assigned, and UL-SCH is transmitted from the mobile station apparatus 3 to the base station apparatus 1 based on this. Here, a sequence focusing on only one mobile station apparatus 3 belonging to the base station apparatus 1 is shown, but the same procedure as in the present embodiment is also performed when a plurality of mobile station apparatuses 3 belong to the base station apparatus 1. It is possible to apply.

  The base station apparatus 1 notifies the mobile station apparatus 3 of the supported number of clusters N (step S101). Here, the notification of N is not necessarily required, and may be determined uniquely by using a value determined in advance in a specification or the like, or by information such as a system bandwidth. In this case, the process of step S101 is omitted. Receiving this, the mobile station apparatus 3 interprets that the resource allocation information received in the future assumes the number N of clusters (step S102).

  Next, the base station apparatus 1 transmits UL-grant including resource allocation information to the mobile station apparatus 3 (step S103). In addition to resource allocation, UL-grant includes information related to MCS, information related to HARQ retransmission control, precoder information related to MIMO, spatial multiplexing information, and the like. Receiving this, the mobile station apparatus 3 interprets the frequency band allocated according to the format in which the resource allocation included in the UL-grant is determined (step S104), and generates the UL-SCH (step S105). It maps to this frequency band (step S106), and transmits to the base station apparatus 1 (step S107). The base station apparatus 1 receives the UL-SCH from the correspondence table between the frequency band held by itself and the assigned mobile station apparatus 3 (step S108). The format of the information bit string of resource allocation and how to interpret it will be described with reference to FIGS. 4A and 4B.

  FIG. 4A is a diagram showing a mechanism of resource allocation transmitted in step S103 of FIG. 3 according to the first embodiment of the present invention (when N = 2). In this figure, the horizontal axis represents the frequency, and represents that the frequency band to be allocated to PUSCH is divided into 10 in units of resource blocks (RB). However, the frequency band targeted for PUSCH allocation may coincide with the system band, and is the frequency band that matches or includes the frequency band to which the PUSCH can be allocated. Here, N = 2 is given from the base station apparatus 1, so that the system bandwidth is two groups (first group: # 1-1 to # 1-5, second group: #) every 5 RBs consecutive. 2-1 to # 2-5). When allocating # 1-3, # 1-4, and # 2-3 to the mobile station apparatus 3, as resources allocation for the first group, resources with # 1-3 as the start position and # 1-4 as the end position An allocation is configured, and a resource allocation is configured with # 2-3 as a start position and # 2-3 as an end position as resource allocation for the second group. As a result, a clustered DFT-S-OFDM signal with two clusters can be generated.

When resource allocation is specified by the LTE method as shown in FIG. 10, the number of bits is simply N times that of SC-FDMA. For example, when the number of RBs corresponding to the system bandwidth is 50 and N = 2, the number of bits necessary for resource allocation is
N × log ₂ (M + M × (M−1) / 2) = 20.6 bits, but when the present invention is applied, N × log ₂ ((M / 2) + (M / 2) × (M / 2) -1) / 2) = 16.7 bits, and information reduction of about 4 bits is possible.

  FIG. 4B is a diagram showing a mechanism of resource allocation transmitted in step S103 of FIG. 3 according to the first embodiment of the present invention (when N = 3). Also in this figure, the horizontal axis represents the frequency and represents that the system bandwidth is divided into 10 in resource block (RB) units. Here, when N = 3 is given from the base station apparatus 1, the system bandwidth is three groups of four, three, and three consecutive RBs (first group: # 1-1 to # 1-4, second Group: # 2-1 to # 2-3, and third group: # 3-1 to # 3-3). When # 1-3, # 2-1, # 2-2, # 2-3, and # 3-1 are allocated to the mobile station device 3, # 1-3 is set as the starting position for resource allocation for the first group. , # 1-3 is the end position, resource allocation is configured, the resource allocation for the second group is # 2-1 is the start position, # 2-3 is the end position, the resource allocation is configured, and the third group is As resource allocation, resource allocation is configured with # 3-1 as the start position and # 3-3 as the end position.

  In this example, since RB # 2-3 and RB # 3-1 are continuous frequency regions, the number of clusters finally generated is two. That is, while it is possible to generate a clustered DFT-S-OFDM signal with the number of clusters being 3, while assigning RBs so that each group is adjacent, the number of clusters N allocated by the base station apparatus 1 It is also possible to generate a DFT-S-OFDM signal with a smaller number of clusters. Similar processing can be easily extended by applying the same processing when N is 4 or more. By the above process, SRS transmitted from the mobile station apparatus 3 belonging to another base station apparatus 1 can be canceled, and the detection accuracy of a desired SRS signal can be improved.

(Second Embodiment)
The mobile communication system according to the second embodiment of the present invention has a base station apparatus 1 shown in FIG. 1 and a mobile station apparatus 3 shown in FIG. Since each component is the same as that of the first embodiment, description thereof is omitted.

  FIG. 5 is a sequence chart showing an operation in which the base station apparatus 1 according to the second embodiment of the present invention allocates a frequency band used for UL-SCH transmission to the mobile station apparatus 3. In FIG. 5, the frequency band which is comprised from the two base station apparatuses 1 and the mobile station apparatus 3 which concern on the 2nd Embodiment of this invention, and is used for transmission of UL-SCH from the base station apparatus 1 to the mobile station apparatus 3 Is assigned, and UL-SCH is transmitted from the mobile station apparatus 3 to the base station apparatus 1 based on this. Here, a sequence focusing on only one mobile station apparatus 3 belonging to the base station apparatus 1 is shown, but the same procedure as in the present embodiment is also performed when a plurality of mobile station apparatuses 3 belong to the base station apparatus 1. It is possible to apply. The difference from the first embodiment is that the frequency band corresponding to the resource allocation is related to the SRS bandwidth. Hereinafter, with respect to the sequence chart of FIG. 5, operation steps (steps S <b> 201 to S <b> 205) different from the first embodiment will be described.

  The base station apparatus 1 notifies the mobile station apparatus 3 of a setting including information regarding the SRS bandwidth (step S201). Receiving this, the mobile station apparatus 3 performs the setting including the SRS bandwidth according to the received setting (step S202). Subsequently, the mobile station apparatus 3 performs SRS transmission (step S203), but a specific procedure related to SRS transmission is omitted.

  Next, the base station apparatus 1 notifies the mobile station apparatus 3 of information on the resource allocation type and information on the number of clusters N (step S204). The resource allocation type indicates what format the bit sequence of the resource allocation is generated based on, for example, whether the resource allocation can represent the entire system bandwidth, or the SRS band A distinction is made as to whether there is a limit depending on the width. Receiving this, the mobile station apparatus 3 interprets the resource allocation received from now on according to the resource allocation type and N (step S205).

  Here, the resource allocation type will be described in detail with reference to FIGS. 4A and 4B and FIGS. 6A and 6B. 4A and 4B match when the resource allocation type notified from the base station apparatus 1 is the entire system bandwidth, and the operation is the same as that of the first embodiment. 6A and 6B match when the resource allocation type notified from the base station apparatus 1 is limited by the SRS bandwidth.

  FIG. 6A is a diagram showing a mechanism of resource allocation transmitted in step S205 of FIG. 5 according to the second embodiment of the present invention (when N = 2). In FIG. 6A, the number of RBs supported by the SRS bandwidth is five. These five RBs are equally divided into two groups (first group: # 1-1 to # 1-3, second group: # 2-1 to # 2-2) according to N = 2. When allocating # 1-2, # 1-3, and # 2-2 to the mobile station apparatus 3, as a resource allocation related to the first group, # 1-2 is a start position and # 1-3 is an end position. An allocation is configured, and a resource allocation is configured with # 2-2 as a start position and # 2-2 as an end position as resource allocation for the second group. As a result, a clustered DFT-S-OFDM signal with two clusters can be generated.

  Compared to the first embodiment, the bit allocation effect of resource allocation can be expected by limiting the RBs that can be allocated, but the flexibility of resource allocation is lost accordingly. Specifically, allocation using this method cannot be performed for a band in which no SRS is transmitted. However, since the frequency band that is generally allocated is based on channel measurement by SRS, the flexibility of scheduling is not lost even if the limitation by the SRS bandwidth is imposed, and the bit size of resource allocation can be reduced. .

  FIG. 6B is a diagram showing a mechanism of resource allocation transmitted in step S205 of FIG. 5 according to the second embodiment of the present invention (when N = 3). In FIG. 6B, the number of RBs supported by the SRS bandwidth is nine. The nine RBs are divided into two groups according to N = 3 (first group: # 1-1 to # 1-3, second group: # 2-1 to # 2-3, third group: # 3 -1 to # 3-3). When # 2-2, # 2-3, # 3-1, and # 3-2 are allocated to the mobile station apparatus 3, # 2-2 is set as the start position for resource allocation related to the second group, # 2-3 Is configured as an end position, and resource allocation is configured with # 3-1 as a start position and # 3-2 as an end position as resource allocation for the third group. Since the first group is not assigned, information specifying it is included in the resource allocation and notified to the mobile station apparatus 3. Since the allocation of the second group and the third group results in a continuous arrangement, a clustered DFT-S-OFDM, that is, an SC-FDMA signal with the number of clusters of 1, can be generated.

  By associating the bandwidth of SRS and the application range of resource allocation by the above processing, the bit size for resource allocation notification can be reduced without losing scheduling flexibility.

  The program that operates in the base station apparatus 1 and the mobile station apparatus 3 according to the present invention is a program (computer function) that controls a CPU (Central Processing Unit) and the like so as to realize the functions of the above-described embodiments according to the present invention. Program). Information handled by these devices is temporarily stored in RAM (Random Access Memory) during the processing, and then stored in various ROMs such as Flash ROM (Read Only Memory) and HDD (Hard Disk Drive). Reading, correction, and writing are performed by the CPU as necessary.

  In addition, you may make it implement | achieve part or all of the mobile station apparatus 3 in the embodiment mentioned above, and the base station apparatus 1 with a computer. In that case, the program for realizing the control function may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read by a computer system and executed. Here, the “computer system” is a computer system built in the mobile station apparatus 3 or the base station apparatus 1 and includes an OS and hardware such as peripheral devices.

  The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” is a medium that dynamically holds a program for a short time, such as a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, In such a case, a volatile memory inside a computer system serving as a server or a client may be included and a program that holds a program for a certain period of time. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

  Moreover, you may implement | achieve part or all of the mobile station apparatus 3 in the embodiment mentioned above and the base station apparatus 1 as LSI (Large Scale Integration) which is typically an integrated circuit. Each functional block of the mobile station device 3 and the base station device 1 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. 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.

  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 the above, and various design changes and the like can be made without departing from the scope of the present invention. It is possible to

DESCRIPTION OF SYMBOLS 1 Base station apparatus 3 Mobile station apparatus 110 Transmission part 111 Coding part 112 Modulation part 113 Mapping part 114 Radio transmission part 120 Scheduling part 121 Uplink transmission frequency band allocation part 122 Uplink resource allocation information generation part 123 SRS band control part 130 Reception unit 131 Radio reception unit 132 SRS separation / calculation unit 133 Inverse mapping / demodulation processing unit 140 Antenna 210 Reception unit 211 Radio reception unit 212 Demodulation processing unit 213 Downlink propagation path calculation unit 220 Scheduling information management unit 221 Uplink resource allocation information Management unit 222 SRS band management unit 230 Transmission unit 231 Encoding unit 232 Modulation unit 233 Mapping unit 234 Wireless transmission unit 240 Antenna

Claims (13)

A mobile station apparatus is a base station apparatus that allocates a frequency band for transmitting data on an uplink and notifies the mobile station apparatus of frequency band allocation information,
A predetermined frequency band is divided into a plurality of continuous groups, a group including the frequency band allocated to the mobile station apparatus is specified, and the start position and end of the frequency band allocated to the mobile station apparatus within the group A scheduling unit for generating bandwidth allocation information including information indicating a position;
A base station apparatus comprising: a base station side transmitting unit that transmits the generated band allocation information to the mobile station apparatus.   The scheduling unit generates the band allocation information so that the mobile station apparatus transmits an uplink data signal using a clustered DFT-S-OFDM (Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing) scheme. The base station apparatus according to claim 1.   The predetermined frequency band is either an entire band that can be used for transmission of PUSCH (Physical Uplink Shared Channel) or a transmission frequency band of SRS (Sounding Reference Signal) transmitted by the mobile station apparatus. The base station apparatus according to claim 2.   The base station apparatus according to claim 3, wherein information indicating either the system band or the transmission frequency band of the SRS is notified to the mobile station apparatus.   The base station apparatus according to claim 1, wherein the base station apparatus notifies the mobile station apparatus of the number of divisions when the predetermined frequency band is divided into a plurality of groups.   An uplink data signal is transmitted to the base station apparatus by a clustered DFT-S-OFDM (Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing) system based on frequency band allocation information received from the base station apparatus according to claim 2 A mobile station apparatus characterized by:   A radio communication system comprising the base station apparatus according to claim 2 and the mobile station apparatus according to claim 6. A control program for a base station apparatus, wherein a mobile station apparatus allocates a frequency band for transmitting data on an uplink, and notifies the mobile station apparatus of frequency band allocation information,
A process of dividing a predetermined frequency band into a plurality of continuous groups;
Processing for identifying a group including a frequency band allocated to the mobile station apparatus and generating band allocation information including information indicating a start position and an end position of a frequency band allocated to the mobile station apparatus in the group;
A control program for a base station apparatus, characterized in that a series of processes including a process of transmitting the generated band allocation information to the mobile station apparatus is commanded to be readable and executable by a computer.   The said mobile station apparatus produces | generates the said band allocation information so that an uplink data signal may be transmitted by a clustered DFT-S-OFDM (Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing) system. Control program for base station equipment. By being mounted on a base station device, an integrated circuit that allows the base station device to perform a plurality of functions,
A function for allocating a frequency band for the mobile station apparatus to transmit data in the uplink;
A function of notifying the mobile station apparatus of frequency band allocation information;
A function of dividing a predetermined frequency band into a plurality of continuous groups;
A function for identifying a group including a frequency band allocated to the mobile station apparatus and generating band allocation information including information indicating a start position and an end position of a frequency band allocated to the mobile station apparatus in the group;
An integrated circuit characterized by causing the base station apparatus to exhibit a series of functions including a function of transmitting the generated band allocation information to the mobile station apparatus.   The said mobile station apparatus produces | generates the said band allocation information so that an uplink data signal may be transmitted with a clustered DFT-S-OFDM (Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing) system. Integrated circuit. A mobile station apparatus is a communication method of a base station apparatus that allocates a frequency band for transmitting data on an uplink and notifies the mobile station apparatus of frequency band allocation information,
The scheduling unit divides a predetermined frequency band into a plurality of continuous groups, specifies a group including the frequency band allocated to the mobile station apparatus, and specifies the frequency band allocated to the mobile station apparatus in the group Generating bandwidth allocation information including information indicating a start position and an end position;
The base station side communication unit includes at least a step of transmitting the generated band allocation information to the mobile station device. The scheduling unit further includes the step of generating the band allocation information so that the mobile station apparatus transmits an uplink data signal by a clustered DFT-S-OFDM (Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing) scheme. The communication method of the base station apparatus according to claim 12.

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