WO2012140847A1

WO2012140847A1 - Transmitter apparatus, receiver apparatus, signal generating method and quality estimating method

Info

Publication number: WO2012140847A1
Application number: PCT/JP2012/002302
Authority: WO
Inventors: 岩井　敬; 西尾　昭彦; 佳彦小川
Original assignee: パナソニック株式会社
Priority date: 2011-04-15
Filing date: 2012-04-02
Publication date: 2012-10-18

Abstract

Provided is a transmitter apparatus that allows a base station to set, for each of a plurality of clusters, OCC sequences, which are to be used at terminals, without increasing the number of signaling bits. A DM-RS information determining unit (205) determines, according to a sequence determination rule, a cyclic shift sequence and an orthogonal sequence that are to be used for DM-RS to be allocated in each of the plurality of clusters. A DM-RS generating unit (206) generates the DM-RS by use of the cyclic shift sequence and orthogonal sequence determined by the DM-RS information determining unit (205). The sequence determination rule includes a plurality of sequence pattern candidates each comprising a first orthogonal sequence to be used at the antenna ports in a cluster (#1) and a second orthogonal sequence to be used at the antenna ports in a cluster (#2). In some of the plurality of pattern candidates, the first and second orthogonal sequences for the same antenna port are different from each other, while in the others of the plurality of pattern candidates, the first and second orthogonal sequences for the same antenna port are the same.

Description

Transmitting apparatus, receiving apparatus, signal generation method, and quality estimation method

The present invention relates to a transmission device, a reception device, a signal generation method, and a quality estimation method that perform discontinuous band allocation.

In LTE-Advanced uplink, which is an extension of 3GPP LTE (3rd Generation Partnership Project Project Long Term Evolution), two technologies are being studied to improve scheduling gain through flexible frequency resource allocation. Transmission and MU-MIMO (Multiple User -Multiple Input Multiple Output).

First, discontinuous band transmission will be described. In LTE, in order to reduce CM (Cubic Metric) and PAPR (Peak to Average Power Ratio), only continuous band transmission that allocates data signals of each terminal to continuous frequency bands is used. On the other hand, in the LTE-Advanced uplink, in order to improve the system throughput performance, it is considered to use non-continuous band transmission in addition to continuous band transmission (for example, see Non-Patent Document 1). . For example, in LTE-Advanced, it is considered that the maximum number of clusters (lumps of continuous bands) in discontinuous band transmission is 2.

Discontinuous band transmission is a method in which data signals and reference signals are allocated and transmitted in discontinuous frequency bands distributed over a wide band. As shown in FIG. 1, in continuous band transmission, a data signal and a reference signal are allocated to continuous frequency bands. On the other hand, in non-continuous band transmission, the data signal and the reference signal can be assigned to discrete frequency bands (here, two clusters). Therefore, in the non-continuous band transmission, the degree of freedom of frequency resource allocation of the data signal and reference signal of each terminal is improved with respect to the continuous band transmission, so that a larger frequency scheduling gain can be obtained. Hereinafter, a case where the number of clusters at the time of non-continuous band transmission is two will be described as an example assuming LTE-Advanced.

Next, MU-MIMO will be described. MU-MIMO is a technique in which a plurality of terminals perform MIMO communication with a base station, and can improve the frequency utilization efficiency of the system and improve the system throughput performance. In MU-MIMO, for example, transmission data of each terminal (transmission side) is separated at a base station (reception side). For this reason, it is necessary to orthogonalize DM-RS (DeModulation-Reference Signal) of each terminal. MIMO is a technique that includes a plurality of antennas on the transmission side and the reception side, respectively, and enables simultaneous spatial multiplexing transmission of different signal sequences at the same frequency.

In LTE, a cyclic shift (CS) sequence that is an orthogonal sequence is used as the DM-RS. The cyclic shift sequence is generated, for example, by cyclically shifting a ZC (Zadoff-Chu) sequence that is a code sequence by a cyclic shift amount (CS amount) in the time domain. FIG. 2 shows a cyclic shift sequence when ZC sequence length (N) = 12, and cyclic shift amount (Δ) = 0 and 6. The cyclic shift sequence of Δ = 0 shown in FIG. 2 is configured in the order of a (0) to a (11). On the other hand, the cyclic shift sequence of Δ = 6 shown in FIG. 2 is a sequence obtained by cyclically shifting the cyclic shift sequence of Δ = 0 by 6 samples, and a (6) to a (11), a (0) to a (5) are configured in this order. The cyclic shift amount (Δ) is determined by the base station and notified from the base station to the terminal using the downlink channel. The downlink channel is, for example, PDCCH (Physical Downlink Control Channel: PDCCH).

Here, in an ideal environment with no propagation path fluctuation, a cyclic shift sequence having the same transmission band is a complete orthogonal sequence, and no inter-sequence interference occurs. On the other hand, in a real environment with propagation path fluctuations, even if cyclic shift sequences having the same transmission band are used, perfect orthogonality cannot be maintained, and some inter-sequence interference occurs. Also, cyclic shift sequences with different transmission bands are not orthogonal sequences, and large inter-sequence interference occurs.

Therefore, in LTE-Advanced, it has been agreed to use an OCC (Orthogonal Cover Code) sequence in addition to the cyclic shift sequence adopted by LTE as DM-RS (for example, see Non-Patent Document 2). In LTE-Advanced, by using a cyclic shift sequence and an OCC sequence together, inter-sequence interference can be reduced even in a real environment where there is a propagation path variation when the transmission band is the same. Further, the OCC sequence is an orthogonal sequence even when transmission bands are different. Therefore, it is possible to MU-MIMO multiplex signals of terminals in different transmission bands. Thereby, the freedom degree of frequency scheduling improves and system throughput performance is improved.

FIG. 3 shows an application example of the OCC series. As shown in FIG. 3, one subframe (for example, 1 msec) is composed of two slots (slot # 1 and slot # 2), and each slot has seven symbols (here, LB (LongLBlock) and CP). (Cyclic Prefix)). As shown in FIG. 3, DM-RS is transmitted using the center symbol (LB # 4) of each slot of one subframe.

In FIG. 3, for each DM-RS (cyclic shift sequence) of slot # 1 and slot # 2 constituting one subframe, an OCC sequence of OCC sequence number # 1 (hereinafter referred to as OCC # 1) = [ 1 [1], or OCC sequence number # 2 (hereinafter referred to as OCC # 2) = [1−1]. That is, in FIG. 3, when OCC # 1 is used, a cyclic shift sequence similar to the conventional one is used as DM-RS. On the other hand, when OCC # 2 is used, a cyclic shift sequence similar to the conventional one is used as DM-RS in slot # 1, and a cyclic shift sequence whose phase is inverted (rotated 180 degrees) in slot # 2 is DM-RS. Used as In the following, a case where the sequence length of the OCC sequence is two that can be realized by the subframe configuration in LTE-Advanced will be described. In this case, the number of OCC sequences that can be generated is two (OCC # 1 and OCC # 2).

In LTE-Advanced, the OCC sequence number used by the terminal for generating the DM-RS is uniquely associated with the cyclic shift amount information included in the control information notified in the downlink channel and notified from the base station to the terminal. (See, for example, Non-Patent Document 2).

FIG. 4 is a table showing a correspondence relationship between the cyclic shift amount information used in LTE-Advanced and the OCC sequence. Hereinafter, the table shown in FIG. 4 may be referred to as a “used sequence identification table” for the terminal to identify the OCC sequence number based on the cyclic shift amount information.

In FIG. 4, “Cyclic Shift Field” indicates cyclic shift amount information, “CS value” indicates a cyclic shift amount (unit: [symbol length / 12 (ms)]), and “OCC” indicates an OCC sequence. Further, λ represents an antenna port number of the terminal. Note that, in the LTE-Advanced uplink, SU-MIMO (Single-User-Multiple-Input-Multiple-Output) in which one terminal transmits data signals from a plurality of antenna ports at the same time and the same frequency and spatially multiplexes the data signals is used. Supported.

The cyclic shift amount information (Cyclic Shift Field) notified from the base station to the terminal corresponds to the cyclic shift amount used in the antenna port of λ = 0, and “0, 2, 3, 4, 6, 8, 9, This is information defined by 8 types (3 bits) of “10”. These correspond to a cyclic shift amount of “0, 2, 3, 4, 6, 8, 9, 10” × symbol length / 12 (ms). Also, [1 1] shown in FIG. 4 is OCC # 1, and [1-1] is OCC # 2. The cyclic shift amounts used in the OCC sequence and other antenna ports (λ = 1 to 3) are also uniquely associated with the cyclic shift amount information (Cyclic Shift Field) based on the correspondence shown in FIG. Be notified.

In SU-MIMO, in order to reduce the amount of control information for frequency resource allocation, the transmission bandwidths of a plurality of streams (transmission signals transmitted from each antenna port) transmitted by one terminal are the same. Therefore, in SU-MIMO, the orthogonality of DM-RS in each stream can be maintained by making the cyclic shift amounts of DM-RS transmitted in each stream different from each other.

On the other hand, in MU-MIMO, the base station can notify each terminal of the transmission bandwidth. Therefore, when the transmission bandwidth differs between terminals performing MU-MIMO, as described above, orthogonality in DM-RS cannot be maintained even if the cyclic shift amount of the terminal is varied. For this reason, it is necessary to make the DM-RS orthogonal by changing the OCC sequence number between terminals performing MU-MIMO.

Also, the use sequence identification table shown in FIG. 4 is used for both continuous band transmission and non-continuous band transmission. That is, at the time of non-continuous band transmission, the OCC sequence number used for the DM-RS of each cluster transmitted from the terminal is the same.

In the above prior art, the OCC sequence numbers used for DM-RSs in each cluster transmitted by one terminal during non-continuous band transmission are the same, and MU-MIMO can be performed without DM-RSs being orthogonal between terminals. Bands that disappear can occur.

For example, a case where three terminals # 1 to # 3 perform MU-MIMO will be described with reference to FIG. In FIG. 5, each terminal performs discontinuous band transmission using two clusters. Also, in FIG. 5, each terminal determines an OCC sequence used for DM-RS in each cluster (that is, the same OCC sequence in all clusters), for example, according to the use sequence identification table shown in FIG. For example, in FIG. 5, terminal # 1 uses OCC # 2, terminal # 2 uses OCC # 1, and terminal # 3 uses OCC # 1.

As shown in FIG. 5, the frequency bands of the cluster # 1 of the terminal # 1 and the cluster # 1 of the terminal # 2 partially overlap. However, as shown in FIG. 5, since the OCC sequences used by terminal # 1 and terminal # 2 are different from each other, DM-RSs are orthogonal. The same applies to the cluster # 2 of the terminal # 1 and the cluster # 1 of the terminal # 3 shown in FIG.

On the other hand, the cluster # 2 of the terminal # 2 and the cluster # 2 of the terminal # 3 shown in FIG. 5 partially overlap in frequency bands and have the same OCC sequence (OCC # 1) used in both. For this reason, cluster # 2 of terminal # 2 and cluster # 2 of terminal # 3 are not orthogonal (non-orthogonal), and inter-sequence interference occurs. As described above, since a band where MU-MIMO cannot be performed (band that cannot be orthogonalized between DM-RSs) occurs, the base station schedules frequency resources with priority given to a band with good channel quality of each terminal. I can't. That is, there is a problem that the effect of improving the system performance by MU-MIMO is limited.

As a method of solving the above problem, a method of newly adding a signaling bit (notification information) for notifying an OCC sequence number at the time of non-continuous band transmission as control information notified by a downlink channel is conceivable. Thereby, the base station can notify the terminal of the OCC sequence number for each cluster. For example, the OCC sequence multiplied by the DM-RS of one of the two clusters (here, cluster # 1) is the cyclic shift amount information (3 bits) notified to the terminal by the base station as described above. (For example, refer to FIG. 4). The OCC sequence to be multiplied by the DM-RS of the other cluster (here, cluster # 2) is notified by the signaling bit. Therefore, when discontinuous band transmission of a maximum of 2 clusters is performed, the signaling bit to be added is 1 bit. For example, the OCC sequence used in cluster # 2 is the same OCC sequence as the OCC sequence used in cluster # 1 when the signaling bit is “0”, and is the cluster # 1 when the signaling bit is “1”. The OCC sequence is different from the OCC sequence used.

For example, the terminal # 1 shown in FIG. 6 is notified of the OCC # 2 by the cyclic shift amount information to the cluster # 1. Further, terminal 0 is notified of “0” by a signaling bit (1 bit). Therefore, the terminal # 1 uses the OCC # 2 in the cluster # 1 and uses the same OCC # 2 as the cluster # 1 in the cluster # 2. The same applies to terminal # 2 shown in FIG. On the other hand, the terminal # 3 shown in FIG. 6 is notified of the OCC # 1 by the cyclic shift amount information to the cluster # 1. Also, the terminal # 3 is notified of “1” by a signaling bit (1 bit). Therefore, terminal # 3 uses OCC # 1 in cluster # 1, and uses (reverse) OCC # 2 different from cluster # 1 in cluster # 2.

In this way, since the base station can freely set the OCC sequence (OCC sequence number) for each cluster, the degree of freedom of frequency scheduling in MU-MIMO without being restricted by MU-MIMO (see, for example, FIG. 5). Can improve system throughput performance.

However, when a signaling bit for notifying the OCC sequence is newly added, there is a problem that the number of signaling bits increases as the number of clusters set in the terminal increases. Further, as described above, when the maximum number of clusters is 2, the number of signaling bits is 1 bit. However, since PDCCH (physical layer control channel) is used for signaling, the coverage of the control channel may be reduced even if the information amount is increased by only 1 bit, or a new payload size (payload size) at the terminal. It may be necessary to add a circuit for receiving the signal.

An object of the present invention is to provide a transmission device, a reception device, a signal generation method, and a quality estimation method that allow a base station to set an OCC sequence used in a terminal for each cluster without increasing the number of signaling bits. It is.

The transmission apparatus according to one aspect of the present invention includes, according to a sequence determination rule, any one of a plurality of cyclic shift sequences that can be separated from each other by different cyclic shift amounts, and any one of a plurality of orthogonal sequences that are orthogonal to each other. Generating means for generating a reference signal based on the transmission means, and transmitting means arranged in each of a plurality of clusters for transmitting a transmission signal including the reference signal from at least one antenna port. The cluster includes a first cluster and a second cluster, and the sequence determination rule includes a first orthogonal sequence used in each antenna port in the first cluster, and each antenna port in the second cluster. A plurality of pattern candidates of a sequence composed of the second orthogonal sequence used, and some of the plurality of pattern candidates In complement, the first orthogonal sequence and the second orthogonal sequence for the same antenna port are different from each other, and the pattern candidates other than the partial pattern candidates are the first orthogonal sequence and the second orthogonal sequence for the same antenna port. The configuration is the same.

A receiving apparatus according to one embodiment of the present invention includes any one of a plurality of cyclic shift sequences arranged in each of a plurality of clusters and separable from each other by different cyclic shift amounts, and a plurality of orthogonal sequences orthogonal to each other. Channel quality is estimated using reception means for receiving a signal including a reference signal generated based on any one of them, a cyclic shift sequence and an orthogonal sequence determined according to a sequence determination rule, and the reference signal And a plurality of clusters including a first cluster and a second cluster, and the sequence determination rule includes a first orthogonal sequence used at each antenna port in the first cluster, and , Including a plurality of pattern candidates of a sequence composed of a second orthogonal sequence used at each antenna port in the second cluster, Among the pattern candidates, in some pattern candidates, the first orthogonal sequence and the second orthogonal sequence for the same antenna port are different from each other. A configuration is employed in which one orthogonal sequence and the second orthogonal sequence are the same.

A signal generation method according to an aspect of the present invention includes a plurality of orthogonal shift sequences that are transmitted from at least one antenna port and that can be separated from each other by different cyclic shift amounts, and a plurality of orthogonal sequences that are orthogonal to each other. A signal generation method for generating a reference signal based on any one of the above, and used for the reference signal arranged in each of a plurality of clusters including a first cluster and a second cluster according to a sequence determination rule A cyclic shift sequence and an orthogonal sequence are determined, and the sequence determination rule includes a first orthogonal sequence used at each antenna port in the first cluster and a second orthogonal sequence used at each antenna port in the second cluster. A plurality of pattern candidates of a sequence consisting of orthogonal sequences, and some pattern candidates among the plurality of pattern candidates The first orthogonal sequence and the second orthogonal sequence for the same antenna port are different from each other, and the pattern candidates other than the partial pattern candidates include the first orthogonal sequence and the second orthogonal sequence for the same antenna port. To be identical.

A quality estimation method according to an aspect of the present invention includes a plurality of orthogonal shift sequences orthogonal to each other and any one of a plurality of cyclic shift sequences that are received by at least one antenna port and can be separated from each other by different cyclic shift amounts. A quality estimation method for estimating channel quality using a reference signal generated based on any one of the above, a cyclic shift sequence and an orthogonal sequence determined according to a sequence determination rule, and the received reference signal And the plurality of clusters include a first cluster and a second cluster, and the sequence determination rule is a first orthogonality used at each antenna port in the first cluster. Including a plurality of pattern candidates of a sequence consisting of a sequence and a second orthogonal sequence used at each antenna port in the second cluster. Among the plurality of pattern candidates, in some pattern candidates, the first orthogonal sequence and the second orthogonal sequence for the same antenna port are different from each other, and in the pattern candidates other than the some pattern candidates, the same antenna is used. The first orthogonal sequence and the second orthogonal sequence for a port are the same.

According to the present invention, the base station can set the OCC sequence used by the terminal for each cluster without increasing the number of signaling bits.

The figure which shows the mode of continuous band allocation and non-continuous band allocation The figure which shows an example of a cyclic shift series The figure which shows an example of the OCC series The figure which shows the correspondence of cyclic shift amount information, cyclic shift amount, and OCC series The figure which shows a mode that the band which becomes non-orthogonal generate | occur | produces in the cluster between the terminals which apply MU-MIMO. The figure which shows a mode that an OCC series is notified for every cluster using a signaling bit. The block diagram which shows the main structures of the base station which concerns on one embodiment of this invention The block diagram which shows the main structures of the terminal which concerns on one embodiment of this invention The block diagram which shows the structure of the base station which concerns on one embodiment of this invention The block diagram which shows the structure of the terminal which concerns on one embodiment of this invention The figure which shows the corresponding relationship of cyclic shift amount information, cyclic shift amount, and an OCC series which concerns on one embodiment of this invention (setting example 1) The figure which shows a mode that an OCC series is set for every cluster which concerns on one embodiment of this invention. The figure which shows the correspondence of the cyclic shift amount information which concerns on one embodiment of this invention, a cyclic shift amount, and an OCC series (setting example 2) The figure which shows the correspondence of the cyclic shift amount information which concerns on one embodiment of this invention, a cyclic shift amount, and an OCC series (setting example 3) The figure which shows the correspondence of the cyclic shift amount information which concerns on one embodiment of this invention, a cyclic shift amount, and an OCC series (setting example 4) The figure which shows the subject which concerns on the example 4 of a setting of one embodiment of this invention The block diagram which shows the structure of the other base station of this invention The block diagram which shows the structure of the other terminal of this invention The figure which shows a mode that an OCC series is set for every other cluster of this invention. The figure which shows a mode that an OCC series is set for every other cluster of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, in the embodiment, components having the same function are denoted by the same reference numerals, and redundant description is omitted.

In the following description, as an example, the transmission device according to each embodiment of the present invention is a terminal device, and the reception device is a base station device.

(Embodiment 1)
FIG. 7 shows the main components of base station 100 according to the present embodiment. The base station 100 shown in FIG. 7 includes any one of a plurality of cyclic shift sequences (CS sequences) separable from each other by different cyclic shift amounts, and any one of a plurality of orthogonal sequences (OCC sequences) orthogonal to each other. The channel quality is estimated using the reference signal (DM-RS) generated based on the above. In base station 100 shown in FIG. 7, receiving section 105 receives a signal including DM-RS, which is arranged in each of a plurality of clusters and transmitted from a terminal apparatus. The estimation unit 112 estimates the channel quality using the cyclic shift sequence and OCC sequence determined according to the used sequence specification table (sequence determination rule) and the received DM-RS.

FIG. 8 shows main components of terminal 200 according to the present embodiment. Terminal 200 shown in FIG. 8 is generated based on any one of a plurality of cyclic shift sequences that can be separated from each other by different cyclic shift amounts and any one of a plurality of orthogonal sequences (OCC sequences) orthogonal to each other. DM-RS to be transmitted from at least one antenna port. In terminal 200 shown in FIG. 8, generating section 213 generates a DM-RS using a cyclic shift sequence and an orthogonal sequence determined according to a used sequence identification table (sequence determination rule). The transmission unit 212 transmits a transmission signal including DM-RS arranged in each of the plurality of clusters.

However, the plurality of clusters include two clusters (cluster # 1 and cluster # 2), and the use sequence identification table (sequence determination rule) includes the first orthogonal sequence used in each antenna port in cluster # 1. , Including a plurality of pattern candidates of a sequence composed of the second orthogonal sequence used in each antenna port in cluster # 2, and some of the pattern candidates include a first orthogonal sequence for the same antenna port, The second orthogonal sequence is different from each other, and in the pattern candidates other than some pattern candidates, the first orthogonal sequence and the second orthogonal sequence for the same antenna port are the same.

[Configuration of Base Station 100]
FIG. 9 is a block diagram showing a configuration of base station 100 according to the present embodiment.

In base station 100 shown in FIG. 9, control information encoding section 101 controls frequency resource allocation information for each terminal 200, MCS (ModulationModCoding Scheme), transmission power, and transmission weight for each antenna port. Control information including weight control information and the like is input from the scheduling unit 113. In addition, control information including cyclic shift amount information constituting a DM-RS to be transmitted by each terminal 200 is input from the DM-RS information determination unit 114 to the control information encoding unit 101. The control information encoding unit 101 encodes the control information and outputs the encoded control information to the modulation unit 102.

The modulation unit 102 modulates the control information input from the control information encoding unit 101 and outputs the modulated signal to the transmission unit 103.

The transmission unit 103 performs transmission processing such as D / A (Digital-to-Analog) conversion, up-conversion, amplification, and the like on the signal input from the modulation unit 102, and transmits the signal subjected to the transmission processing to one or more antennas The data is transmitted from the ports 104-1 and 104-2 to each terminal 200.

The receiving units 105-1 and 105-2 and the reception processing units 106-1 and 106-2 are provided corresponding to the antenna ports 104-1 and 104-2.

Receiving sections 105-1 and 105-2 receive signals from terminals 200 received via antenna ports 104-1 and 104-2, such as down-conversion and A / D (Analog to Digital) conversion. Processing is performed, and the signal subjected to the reception processing is output to each of the separation units 107 of the reception processing units 106-1 and 106-2.

The reception processing units 106-1 and 106-2 employ a configuration including a separation unit 107, DFT (Discrete Fourier Transform)

units

108 and 110, and

demapping units

109 and 111, respectively.

The separating unit 107 separates the signal input from the receiving unit 105 into a DM-RS and a data signal. Separation section 107 then outputs the DM-RS to DFT section 108 and outputs the data signal to DFT section 110.

The DFT unit 108 performs DFT processing on the DM-RS input from the separation unit 107, and converts the signal from the time domain to the frequency domain. Then, the DFT unit 108 outputs the DM-RS converted into the frequency domain to the demapping unit 109.

The demapping unit 109 extracts a part of the DM-RS corresponding to the transmission band of the terminal 200 (desired terminal) to receive from the frequency domain DM-RS input from the DFT unit 108, and extracts the extracted DM-RS. Is output to the estimation unit 112.

On the other hand, the DFT unit 110 performs DFT processing on the data signal input from the separation unit 107, and converts the data signal from the time domain to the frequency domain. Then, the DFT unit 110 outputs the data signal converted into the frequency domain to the demapping unit 111.

Demapping section 111 extracts a data signal corresponding to the transmission band of terminal 200 (desired terminal) to receive from the frequency domain data signal input from DFT section 110, and MIMO-separates the extracted data signal Output to the unit 115.

The estimation unit 112 receives information (cyclic shift sequence and OCC sequence) input from a DM-RS information determination unit 114, which will be described later, and each demapping unit 109 of the reception processing units 106-1 and 106-2. Channel quality (frequency response of the channel) and reception quality are estimated using DM-RS (sometimes referred to as “reception DM-RS”). Specifically, estimation section 112 calculates a DM-RS replica signal transmitted by the desired terminal based on the cyclic shift sequence and OCC sequence determined by DM-RS information determination section 114. Then, the estimation unit 112 estimates the channel quality and reception quality of the desired terminal by performing a correlation operation between the received DM-RS and the generated replica signal. Then, estimation section 112 outputs an estimated value of channel quality (channel frequency response) used for demodulation of the data signal to MIMO demultiplexing section 115 and outputs an estimation value of reception quality used for scheduling to scheduling section 113.

The scheduling unit 113 determines the transmission band (frequency resource), transmission power, and transmission weight of each antenna port of the transmission signal transmitted by each terminal 200 according to the reception quality estimation value input from the estimation unit 112. Then, scheduling section 113 outputs control information including the determined information to control information encoding section 101. In addition, scheduling section 113 outputs information including the number of transmission antenna ports of each terminal 200 and the transmission band of each terminal 200 to DM-RS information determination section 114.

DM-RS information determination section 114 circulates for DM-RS used in each antenna port of each terminal 200 based on the number of transmission antenna ports of each terminal 200 and the transmission band of each terminal 200 input from scheduling section 113. A shift sequence and an OCC sequence are determined. Here, the cyclic shift sequences are sequences that can be separated from each other by different cyclic shift amounts. The OCC sequences are sequences orthogonal to each other. For example, the DM-RS information determination unit 114 previously stores a table (hereinafter referred to as a used sequence identification table) in which cyclic shift amount information is associated with each sequence number (cyclic shift sequence number and OCC sequence number). Hold. The use sequence identification table is shared between the base station 100 and each terminal 200. Then, the DM-RS information determination unit 114 refers to the use sequence identification table using the number of antenna ports and the transmission band (for example, the number of clusters) set for each terminal 200, and sets each antenna port of each terminal 200. The cyclic shift sequence and OCC sequence for DM-RS used in the above are selected. That is, DM-RS information determination section 114 determines cyclic shift sequences and OCC sequences used for DM-RSs arranged in each of a plurality of clusters set in terminal 200. Here, DM-RS information determining section 114 performs cyclic shift sequence between terminals 200 with overlapping transmission bands (that is, between terminals 200 to which MU-MIMO is applied) in order to reduce inter-sequence interference of DM-RS. The numbers or OCC sequence numbers need to be different from each other. DM-RS information determination section 114 outputs cyclic shift amount information associated with the cyclic shift sequence number and OCC sequence number used by each terminal 200 to control information encoding section 101.

That is, the cyclic shift sequence number and the OCC sequence number constituting the DM-RS to be transmitted from each antenna port by terminal 200 are used sequence base table shared between base station 100 and terminal 200, base station 100 Is indirectly notified by the cyclic shift amount information notified from the terminal 200 to the terminal 200. Details of the use sequence identification table will be described later.

MIMO separation section 115 uses the estimated frequency response value of the channel input from estimation section 112 to convert the data signals input from demapping sections 111 of reception processing sections 106-1 and 106-2, respectively, into the frequency domain. Equalize and multiply by a predetermined weight. As a result, the data signal is separated into data signals (transmission signals transmitted from the respective antenna ports) of each stream. Then, MIMO separation section 115 outputs the data signal of each separated stream to each IFFT (Inverse Fast Fourier Transform) section 117 of data processing sections 116-1 and 116-2.

The data processing units 116-1 and 116-2 are provided corresponding to the number of streams transmitted from the terminal 200, and have a configuration including an IFFT unit 117, a demodulation unit 118, and a decoding unit 119, respectively.

The IFFT unit 117 performs IFFT processing on the data signal input from the MIMO separation unit 115 and outputs the data signal after IFFT processing to the demodulation unit 118.

Demodulation section 118 performs demodulation processing on the data signal input from IFFT section 117 and outputs the demodulated data signal to decoding section 119.

Decoding section 119 performs a decoding process on the data signal input from demodulation section 118 and outputs the data signal as received data from terminal 200.

[Configuration of terminal 200]
FIG. 10 is a block diagram showing a configuration of terminal 200 according to the present embodiment.

In terminal 200 shown in FIG. 10, receiving section 202 performs down-conversion, A / D conversion, etc., on the signal from base station 100 (FIG. 9) received via at least one antenna port 201-1 and 201-2. The reception process is performed, and the signal subjected to the reception process is output to the demodulation unit 203. The received signal includes frequency resource allocation information for terminal 200, MCS of transmission data, transmission power, weight control information for each antenna port, and control information including cyclic shift amount information.

The demodulation unit 203 performs equalization processing and demodulation processing on the reception signal input from the reception unit 202, and outputs the reception signal subjected to these processing to the decoding unit.

The control information decoding unit 204 performs a decoding process on the received signal input from the demodulation unit 203, and extracts control information from the signal after the decoding process. Control information decoding section 204 outputs cyclic shift amount information to DM-RS information determination section 205, outputs MCS of transmission data to modulation section 208, outputs resource allocation information to mapping section 209, and sends it to each antenna port. Is output to the transmission weight multiplier 211.

The DM-RS information determination unit 205 holds a use sequence identification table shared between the base station 100 and the terminal 200. DM-RS information determination section 205 performs cyclic shift for generating DM-RS to be transmitted by terminal 200 at each antenna port according to the cyclic shift amount information input from control information decoding section 204 and the use sequence identification table. A sequence number and an OCC sequence number are determined. DM-RS information determination section 205 outputs the determined cyclic shift sequence number and OCC sequence number to DM-RS generation section 206.

DM-RS generating section 206 generates a DM-RS using the cyclic shift sequence number and OCC sequence number used at each antenna port, which are input from DM-RS information determining section 205, and multiplexes DM-RS 210 Output to. Specifically, DM-RS generating section 206 spreads the cyclic shift sequence corresponding to the cyclic shift amount set by DM-RS information determining section 205 with the OCC sequence set by DM-RS information determining section 205. Then, the spread signal is generated as DM-RS.

Note that, as shown in FIG. 10, the generation unit 213 may be configured by combining the configurations of the DM-RS information determination unit 205 and the DM-RS generation unit 206. That is, the generation unit 213 generates a DM-RS composed of a cyclic shift sequence and an OCC sequence in accordance with a use sequence identification table (sequence determination rule).

The data processing units 207-1 and 207-2 are provided corresponding to the antenna ports 201-1 and 201-2, and have a configuration including a modulation unit 208, a mapping unit 209, and a multiplexing unit 210, respectively.

The modulation unit 208 performs encoding processing and modulation processing on transmission data based on the MCS input from the control information decoding unit 204, and outputs the modulated data signal to the mapping unit 209.

The mapping unit 209 maps the data signal input from the modulation unit 208 to a cluster that is a predetermined frequency resource based on the frequency resource allocation information input from the control information decoding unit 204 and outputs the data signal to the multiplexing unit 210.

The multiplexing unit 210 time-multiplexes the data signal input from the mapping unit 209 and the DM-RS input from the DM-RS generation unit 206, and outputs the multiplexed signal to the transmission weight multiplication unit 211.

As shown in FIG. 10, the arrangement unit 214 may be configured by combining the configurations of the mapping unit 209 and the multiplexing unit 210. That is, arrangement section 214 (arrangement section 214 corresponding to the antenna port used for transmission), based on the frequency resource allocation information, distributes transmission signals including data signals and DM-RS to a plurality of clusters that are frequency resources. Place each one.

Based on transmission weight information input from control information decoding section 204, transmission weight multiplication section 211 multiplies each multiplexed signal input from each multiplexing section 210 of data processing sections 207-1 and 207-2 by a transmission weight. Then, the multiplexed signals after multiplication are output to transmission sections 212-1 and 212-2, respectively.

The transmission units 212-1 and 212-2 are provided corresponding to the antenna ports 201-1 and 201-2. Each transmission unit 212 performs transmission processing such as D / A conversion, up-conversion, and amplification on the multiplexed signal input from the transmission weight multiplication unit 211, and transmits the signal subjected to the transmission processing to the antenna ports 201-1 and 201. -2 to base station 100. Thereby, the DM-RS is transmitted from at least one antenna port 201-1 and 201-2 to the base station 100.

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

In the following description, assuming that LTE-Advanced is assumed, the case where the number of clusters during discontinuous band transmission is two will be described.

Also, the maximum number of antenna ports that can be used in terminal 200 is four (antenna port number λ = 0 to 3), and terminal 200 uses at least one of the four antenna ports to transmit DM-RS to the base station. To 100.

In the following description, the ZC sequence length (N) is 12 and the cyclic shift amount (Δ) = 8 types of “0, 2, 3, 4, 6, 8, 9, 10”. The OCC sequence length is 2, OCC # 1 = [1 1], and OCC # 2 = [1−1].

In addition, when the frequency resource allocation information for the terminal 200 indicates continuous band transmission (number of clusters: 1), the base station 100 and the terminal 200 are based on a use sequence identification table (for example, see FIG. 4) used in LTE. The cyclic shift sequence number and OCC sequence number used as DM-RS are specified.

On the other hand, when the frequency resource allocation information for terminal 200 indicates discontinuous band transmission (number of clusters: 2, for example, cluster # 1 and cluster # 2), base station 100 and terminal 200 use sequences for discontinuous band transmission. Based on the identification table, the cyclic shift sequence number and the OCC sequence number used as DM-RSs transmitted respectively in cluster # 1 and cluster # 2 are identified. Note that the cyclic shift sequence used as the DM-RS transmitted in each cluster during discontinuous band transmission is common (identical) between the clusters.

In addition, the used sequence identification table used in each of continuous band transmission and non-continuous band transmission includes a plurality of pattern pattern candidates including a cyclic shift sequence (cyclic shift amount) and an OCC sequence (OCC sequence number) ( 8 types here). More specifically, the used sequence identification table used for non-continuous band transmission includes a cyclic shift sequence, an OCC sequence used in each antenna port (λ = 0 to 3) in cluster # 1, and each antenna in cluster # 2. It includes a plurality of pattern candidates for sequences consisting of OCC sequences used at ports (λ = 0 to 3). The cyclic shift amount information and the pattern candidates of the plurality of sequences are associated on a one-to-one basis.

Then, the base station 100 corresponds to “0, 2, 3, 4, 6, 8,” corresponding to the cyclic shift amount used in the antenna port of λ = 0 in both continuous band transmission and non-continuous band transmission. The terminal 200 is notified of cyclic shift amount information (Cyclic Shift Field) defined by 8 types (3 bits) of “9, 10”.

On the other hand, terminal 200 identifies the cyclic shift sequence and the OCC sequence for each cluster according to the usage sequence identification table and the cyclic shift amount information notified from base station 100. Thus, the cyclic shift sequence number and the OCC sequence number constituting the DM-RS in each cluster to be transmitted from each antenna port by terminal 200 are indirectly notified by the cyclic shift amount information notified from base station 100. Is done.

In this embodiment, in the use sequence identification table used at the time of non-continuous band transmission, the OCC sequence of cluster # 1 is the same OCC sequence as at the time of continuous band transmission (see FIG. 4). That is, the correspondence between the cyclic shift amount information (Cyclic Shift Field) and the OCC sequence of cluster # 1 transmitted from each antenna port (λ = 0 to 3) is the same as that during continuous band transmission (see FIG. 4). It becomes.

On the other hand, in the use sequence identification table used at the time of non-continuous band transmission, the OCC sequence of cluster # 2 is different from the OCC sequence obtained by inverting the OCC sequence of cluster # 1 (that is, the OCC sequence of cluster # 1). (OCC series) is partially included. That is, among the eight types of pattern candidates indicated in the cyclic shift amount information (Cyclic Shift Field), some of the pattern candidates have different OCC sequences for cluster # 1 and OCC sequences for cluster # 2 for the same antenna port. . That is, within the pattern candidate, when the OCC sequence of cluster # 1 at a certain antenna port is OCC # 1, the OCC sequence of cluster # 2 is cluster # 2, and the OCC sequence of cluster # 1 is OCC # 2. In this case, the OCC sequence of cluster # 2 is cluster # 1. On the other hand, the OCC sequence of cluster # 1 and the OCC sequence of cluster # 2 are the same for the same antenna port in other pattern candidates other than the part of the patterns described above.

Hereinafter, setting examples 1 to 4 of the use sequence identification table at the time of non-continuous band transmission will be described.

Note that, as described above, in the use sequence identification table (FIGS. 11, 13, 14, and 15 described later) in the discontinuous band transmission in each setting example, “Cyclic Shift Field” is cyclic shift information (3 bits). “CS value” indicates the cyclic shift amount used for the antenna port number λ, “OCC (Cluster # 1)” indicates the OCC sequence used for the cluster # 1 of the antenna port number λ, and “OCC (Cluster # 2) ")" Indicates an OCC sequence used in cluster # 2 of antenna port number λ.

In addition, in the use sequence specification table (FIGS. 11, 13, 14, and 15 described later) at the time of non-continuous band transmission in each setting example, “CycliccShift Field”, “CS value”, “OCC (Cluster # 1 ) ”Is the same as the correspondence relationship (Cyclic Shift Field”, “CS value”, and “OCC (Cluster # 1)” shown in FIG. 4 (used sequence identification table during continuous band transmission). .

<Setting example 1 (FIG. 11)>
FIG. 11 shows an example of a use sequence identification table (sequence determination rule) at the time of discontinuous band transmission in setting example 1.

Among the eight types of cyclic shift amount information shown in FIG. 11 (that is, eight types of pattern candidates), in some cyclic shift amount information, the OCC sequence and cluster # 2 used in cluster # 1 for the same antenna port are used. The OCC sequences used are different from each other, and in other cyclic shift amount information, the OCC sequences used in cluster # 1 and the OCC sequences used in cluster # 2 for the same antenna port are the same.

For example, in the cyclic shift information = '000' shown in FIG. 11, the OCC sequences used in cluster # 1 are [OCC # 1, OCC # 1, OCC # 2, OCC # 2 in the order of λ = 0-3. The OCC sequences used in cluster # 2 are [OCC # 1, OCC # 1, OCC # 2, OCC # 2] in the order of λ = 0 to 3. That is, in cyclic shift information = '000', the OCC sequence pattern used in each antenna port is the same between cluster # 1 and cluster # 2. The same applies to cyclic shift information = “001” shown in FIG.

On the other hand, for example, in the cyclic shift information = '010' shown in FIG. 11, the OCC sequences used in the cluster # 1 are [OCC # 2, OCC # 2, OCC #] in order of λ = 0-3. 1, OCC # 1], and the OCC sequences used in cluster # 2 are [OCC # 1, OCC # 1, OCC # 2, OCC # 2] in the order of λ = 0 to 3. That is, when cyclic shift information = '010', the OCC sequence pattern used in each antenna port is inverted between cluster # 1 and cluster # 2. The same applies to cyclic shift information = “011” to “111” shown in FIG.

Accordingly, in the use sequence identification table shown in FIG. 11, the combination of the OCC sequence of cluster # 1 and the OCC sequence of cluster # 2 at each antenna port is [OCC # 1, OCC # 1], [OCC # 1]. , OCC # 2], [OCC # 2, OCC # 1], and [OCC # 2, OCC # 2]. That is, the use sequence identification table shown in FIG. 11 includes all combinations (combinations of four patterns) that can be taken using OCC # 1 and OCC # 2.

When comparing the prior art with the setting example 1, as described above, in the prior art, the same OCC sequence is used in the cluster # 1 and the cluster # 2 in the discontinuous band transmission. Therefore, the combination of the OCC sequence of cluster # 1 and the OCC sequence of cluster # 2 includes a combination of two patterns [OCC # 1, OCC # 1] and [OCC # 2, OCC # 2]. On the other hand, in setting example 1 (FIG. 11), the number of OCC sequences that can be set in each cluster by one terminal 200 can be increased while maintaining the same number of signaling bits (3 bits) as in the prior art. .

For example, the prior art (FIGS. 5 and 6) and the setting example 1 (FIG. 12) are compared. As shown in FIG. 12, base station 100 notifies cyclic shift amount information (3 bits) to terminals 1 to 3 (terminal 200) as in the conventional case. Each of the terminals 1 to 3 specifies the OCC sequences of the cluster # 1 and the cluster # 2 according to the cyclic shift amount information notified from the base station 100 and the use sequence specifying table shown in FIG. Accordingly, in FIG. 12, as in FIG. 6, the base station 100 can set an OCC sequence for each cluster for each of the terminals 1 to 3. In FIG. 12, the number of signaling bits for notifying the OCC sequence is 3 bits as in FIG. Therefore, in setting example 1, it is possible to perform MU-MIMO in the same manner as in FIG. 6 using the same signaling amount as in FIG.

In this way, in setting example 1, base station 100 uses the use sequence identification table shown in FIG. 11, thereby freeing frequency scheduling in MU-MIMO without adding a new signaling bit to the prior art. The degree can be improved. In other words, since a scheduling gain by MU-MIMO can be obtained, system throughput performance can be improved.

Here, pay attention to cyclic shift information = '010' to '100' shown in FIG. As shown in FIG. 11, for example, in antenna port number λ = 0, the cyclic shift amount corresponding to cyclic shift information = “010” is 3, the cyclic shift amount corresponding to “011” is 4, The cyclic shift amount corresponding to 100 ′ is two. That is, the cyclic shift amount corresponding to cyclic shift information = “010” to “100” is an adjacent value (2, 3, 4).

In a cyclic shift sequence, it is known that the orthogonality increases as the interval of the cyclic shift amount increases. For example, when using a ZC sequence having a sequence length of 12, the cyclic shift amounts (Δ) separated by 6 samples (for example, Δ = 0 and 6, Δ = 2 and 8, etc.) have inter-sequence interference. small. On the other hand, the cyclic shift sequences having adjacent cyclic shift amounts (Δ) (for example, Δ = 2 and 3, Δ = 9 and 10, etc.) have large inter-sequence interference. Therefore, in the use sequence identification table (FIG. 4) at the time of continuous band transmission, inter-sequence interference is reduced by assigning different OCC sequences to adjacent cyclic shift sequences at the antenna port number λ = 0, 1. Yes.

On the other hand, in FIG. 11, the OCC sequences in the cyclic shift amount information having adjacent cyclic shift amounts (pattern candidates having large inter-sequence interference in the cyclic shift sequences) are different between cluster # 1 and cluster # 2. . As a result, even during non-consecutive band transmission, different OCC sequences are allocated between terminals 200 using cyclic shift amounts adjacent to both cluster # 1 and cluster # 2 at the antenna port number λ = 0, 1, and therefore between sequences. Interference can be suppressed. Furthermore, by including all combinations (combinations of 4 patterns) that can be taken using OCC # 1 and OCC # 2 at antenna port numbers λ = 0, 1, the degree of freedom of frequency scheduling in MU-MIMO is improved. be able to.

Note that the same applies to cyclic shift information = “010” to “100” for cyclic shift information = “011” to “111” shown in FIG.

<Setting example 2 (FIG. 13)>
FIG. 13 shows an example of a used sequence identification table (sequence determination rule) at the time of discontinuous band transmission in setting example 2.

In the use sequence identification table shown in FIG. 13, as in setting example 1 (FIG. 11), among the 8 types of cyclic shift amount information (that is, 8 types of pattern candidates), some of the cyclic shift amount information uses the same antenna. The OCC sequence used in cluster # 1 for the port and the OCC sequence used in cluster # 2 are different from each other, and in other cyclic shift amount information, the OCC sequence and cluster # used in cluster # 1 for the same antenna port are used. The OCC sequence used in 2 is the same.

As a result, in the use sequence identification table shown in FIG. 13, the combination of the OCC sequence of cluster # 1 and the OCC sequence of cluster # 2 at each antenna port is [OCC # 1] as in setting example 1 (FIG. 11). , OCC # 1], [OCC # 1, OCC # 2], [OCC # 2, OCC # 1], and [OCC # 2, OCC # 2]. That is, the use sequence identification table shown in FIG. 13 includes all combinations (combinations of four patterns) that can be taken using OCC # 1 and OCC # 2.

Therefore, by using the use sequence identification table shown in FIG. 13, the base station 100 can improve the degree of freedom of frequency scheduling in MU-MIMO without adding a signaling bit to the prior art. . In other words, since a scheduling gain by MU-MIMO can be obtained, system throughput performance can be improved.

Here, attention is paid to the cyclic shift information = “011” and “100” shown in FIG. As shown in FIG. 13, both the cyclic shift information = “011” and “100” have the OCC sequence of cluster # 1 (that is, the OCC sequence at the time of continuous band transmission) in all antenna ports. [1 1]).

Among the cyclic shift information = “011” and “100” shown in FIG. 13, in “011”, the OCC sequence of cluster # 2 is the same as the OCC sequence of cluster # 1, and OCC # 1 ( [1 1]). On the other hand, in '100', the OCC sequence of cluster # 2 is inverted from the OCC sequence of cluster # 1 and becomes OCC # 2 ([1−1]) at all antenna ports.

The same applies to the combination of cyclic shift amount information = “101” and “110” shown in FIG.

That is, in the eight types of cyclic shift amount information (pattern candidates) shown in FIG. 13, the OCC sequences used in cluster # 1 are the same in all antenna ports, and the types of the OCC sequences are the same. Among the shift amount information (pattern candidates), on the one hand, the OCC sequence used in cluster # 1 for the same antenna port and the OCC sequence used in cluster # 2 are different from each other, and on the other hand, the cluster # for the same antenna port. The OCC sequence used in 1 and the OCC sequence used in cluster # 2 are the same.

Accordingly, in the use sequence identification table shown in FIG. 13, in the four types of cyclic shift amount information ('011' to '110') in which the same OCC sequence is associated with all antenna ports, OCC # 1 and OCC # 1 All combinations that can be taken using # 2 (4 pattern combinations) are included.

The base station 100 notifies the cyclic shift amount information = '011' to '110' in which the same OCC sequence is associated with all antenna ports to the terminal 200 in which the number of antenna ports is set to 3 or more. There is a high possibility of doing. It is assumed that cyclic shift amount information in which different OCC sequences are associated with each antenna port is notified to another terminal 200 in which the number of antenna ports is set to 3 or more. In this case, a certain terminal 200 can orthogonalize DM-RSs in a band where the transmission band overlaps with a cluster transmitted from the other terminal 200 regardless of whether OCC # 1 or OCC # 2 is used. This is because it can be impossible. Even when the same OCC sequence is used between different antenna ports in one terminal 200, the OCC sequences are not orthogonal. However, in one terminal 200, transmission bands of signals transmitted from all antenna ports are set to be the same. Therefore, in one terminal 200, DM-RS orthogonalization using a cyclic shift sequence can be realized even if DM-RS orthogonalization using an OCC sequence cannot be realized by using the same OCC sequence between antenna ports.

Therefore, the base station 100 uses the use sequence identification table shown in FIG. 13 to provide the maximum number of OCC sequences for cluster # 1 and cluster # 2 for a plurality of terminals 200 transmitting at 3 antenna ports or more. A combination of 4 patterns can be set. That is, base station 100 can improve the degree of freedom of frequency scheduling in MU-MIMO for terminal 200 that transmits with three or more antenna ports.

Similarly, the base station 100 can set four different combinations of OCC sequences for the terminal 200 that transmits with two antenna ports or less. That is, base station 100 can improve the degree of freedom of frequency scheduling in MU-MIMO for terminal 200 that transmits at two antenna ports or less. This improves system throughput performance.

<Setting example 3 (FIG. 14)>
FIG. 14 shows an example of a used sequence identification table (sequence determination rule) at the time of discontinuous band transmission in setting example 3.

In the use sequence identification table shown in FIG. 14, as in setting example 1 (FIG. 11), among the 8 types of cyclic shift amount information (that is, 8 types of pattern candidates), some cyclic shift amount information uses the same antenna. The OCC sequence used in cluster # 1 for the port and the OCC sequence used in cluster # 2 are different from each other, and in other cyclic shift amount information, the OCC sequence and cluster # used in cluster # 1 for the same antenna port are used. The OCC sequence used in 2 is the same.

As a result, in the use sequence identification table shown in FIG. 14, the combination of the OCC sequence of cluster # 1 and the OCC sequence of cluster # 2 at each antenna port is [OCC # 1] as in setting example 1 (FIG. 11). , OCC # 1], [OCC # 1, OCC # 2], [OCC # 2, OCC # 1], and [OCC # 2, OCC # 2]. That is, the use sequence identification table shown in FIG. 14 includes all combinations (combinations of four patterns) that can be taken using OCC # 1 and OCC # 2.

Therefore, by using the used sequence identification table shown in FIG. 14, the base station 100 can improve the degree of freedom of frequency scheduling in MU-MIMO without adding a signaling bit to the prior art. . In other words, since a scheduling gain by MU-MIMO can be obtained, system throughput performance can be improved.

Here, pay attention to cyclic shift information = '000' and '111' shown in FIG. As shown in FIG. 14, for both cyclic shift information = '000' and '111', the OCC sequences of cluster # 1 are in the order of antenna port numbers λ = 0 to 3 in the order of [OCC # 1, OCC # 1, OCC # 2, OCC # 2). That is, in the cyclic shift information = “000” and “111” shown in FIG. 14, the OCC sequence pattern of cluster # 1 is the same.

On the other hand, among the cyclic shift information = “000” and “111” shown in FIG. 14, in “000”, the OCC sequence of cluster # 2 is the same as the OCC sequence of cluster # 1, whereas “111”. Then, the OCC sequence of cluster # 2 is inverted from the OCC sequence of cluster # 1.

The same applies to the cyclic shift amount information = the combination of “001” and “010”, the combination of “011” and “100”, and the combination of “101” and “110” shown in FIG.

That is, in the eight types of cyclic shift amount information (pattern candidates) shown in FIG. 14, two cyclic shifts in which the OCC sequence patterns used in the four antenna ports (λ = 0 to 3) of cluster # 1 are the same. Among the quantity information (pattern candidates, eg, “000” and “111”), on the one hand, the OCC sequence used in cluster # 1 and the OCC sequence used in cluster # 2 for the same antenna port are different from each other. Then, the OCC sequence used in cluster # 1 and the OCC sequence used in cluster # 2 for the same antenna port are the same.

Accordingly, in the use sequence identification table shown in FIG. 14, the same OCC is used in the cluster # 1 and the cluster # 2 in the four types of cyclic shift amount information among the eight types of cyclic shift amount information (pattern candidates). Sequences are associated with each other, and the remaining half of the four types of cyclic shift amount information are associated with different OCC sequences in cluster # 1 and cluster # 2.

As a result, the base station 100 uses the usage sequence identification table shown in FIG. 14, for example, [OCC # 1, OCC #] to the terminal 200 that transmits at 2 antenna ports or less (λ = 0, 1). 1], [OCC # 1, OCC # 2], [OCC # 2, OCC # 1], and [OCC # 2, OCC # 2] can be determined equally two each. Therefore, base station 100 can improve the degree of freedom of frequency scheduling in MU-MIMO for terminal 200 that transmits at two antenna ports or less, compared to setting example 2 (FIG. 13). This improves system throughput performance.

Similarly to setting example 2 (FIG. 13), the base station 100 uses the use sequence identification table shown in FIG. 14 to provide four different OCC patterns for a plurality of terminals 200 transmitting at three antenna ports or more. A combination of sequences (cyclic shift amount information = “011” to “110”) can be set. That is, base station 100 can also improve the degree of freedom of frequency scheduling in MU-MIMO for terminal 200 that transmits with three or more antenna ports.

<Setting example 4 (FIG. 15)>
FIG. 15 shows an example of a used sequence identification table (sequence determination rule) at the time of discontinuous band transmission in setting example 4.

In the use sequence identification table shown in FIG. 15, as in setting example 1 (FIG. 11), among the 8 types of cyclic shift amount information (that is, 8 types of pattern candidates), some cyclic shift amount information uses the same antenna. The OCC sequence used in cluster # 1 for the port and the OCC sequence used in cluster # 2 are different from each other, and in other cyclic shift amount information, the OCC sequence and cluster # used in cluster # 1 for the same antenna port are used. The OCC sequence used in 2 is the same.

As a result, in the use sequence identification table shown in FIG. 15, the combination of the OCC sequence of cluster # 1 and the OCC sequence of cluster # 2 at each antenna port is [OCC # 1] as in setting example 1 (FIG. 11). , OCC # 1], [OCC # 1, OCC # 2], [OCC # 2, OCC # 1], and [OCC # 2, OCC # 2]. That is, the use sequence identification table shown in FIG. 15 includes all combinations (combinations of 4 patterns) that can be taken by OCC # 1 and OCC # 2.

Therefore, by using the used sequence identification table shown in FIG. 15, the base station 100 can improve the degree of freedom of frequency scheduling in MU-MIMO without adding a signaling bit to the prior art. . In other words, since a scheduling gain by MU-MIMO can be obtained, system throughput performance can be improved.

Here, pay attention to cyclic shift information = '000' and '001' shown in FIG. As shown in FIG. 15, when cyclic shift information = '000' and '001', two cyclic shift amounts (CS （value) respectively used in each antenna port at the time of transmission of two antenna ports (λ = 0, 1) are [0, 6] and [6, 0], respectively. That is, when cyclic shift information = '000' and '001', the combination of cyclic shift amounts (0 and 6) used at the time of 2-antenna port transmission is the same.

In the use sequence identification table shown in FIG. 15, a pair of cyclic shift amount information (pattern candidates) having the same combination of cyclic shift amounts used at the time of two-antenna port transmission is “010” in addition to “000” and “001”. And '111' pairs, 011 'and' 110 'pairs, and 100' and '101' pairs.

Next, attention is focused on the above four pairs of cyclic shift information. First, in FIG. 15, focusing on the “000” and “001” pairs and the “100” and “101” pairs among the above four pairs, the OCC sequences are different between cluster # 1 and cluster # 2 ( Is reversed). On the other hand, in FIG. 15, focusing on the 010 'and' 111 'pairs and the 011' and '110' pairs among the above four pairs, the OCC sequences in cluster # 1 and cluster # 2 Are the same.

That is, in the use sequence identification table shown in FIG. 15, one of the pairs of cyclic shift amount information (pattern candidates) in which the combination of two cyclic shift sequences used in each antenna port is the same when two antenna ports are used. In the cyclic shift amount information (pattern candidates) included in a pair of parts, the OCC sequence used in cluster # 1 and the OCC sequence used in cluster # 2 for the same antenna port are different from each other, and other than the above part pairs In the cyclic shift amount information (pattern candidates) included in the pair, the OCC sequence used in cluster # 1 and the OCC sequence used in cluster # 2 for the same antenna port are the same.

That is, in the use sequence identification table shown in FIG. 15, it is determined for each pair described above whether different OCC sequences are set for cluster # 1 and cluster # 2 or the same OCC sequence is set. Further, as shown in FIG. 15, among the eight types of cyclic shift amount information (pattern candidates), half of the four types of cyclic shift amount information are associated with the same OCC sequence in cluster # 1 and cluster # 2. The remaining half of the four types of cyclic shift amount information is associated with different OCC sequences in cluster # 1 and cluster # 2.

Here, for example, a case will be described where, in setting example 3 (FIG. 14), cyclic shift amount information for the same cyclic shift amount used when transmitting two antenna ports is notified to different terminals. For example, as shown in FIG. 16, it is assumed that cyclic shift amount information “011” is notified to terminal # 1, and cyclic shift amount information “110” is notified to terminal # 2. In this case, as shown in FIG. 16, in terminal # 1, cyclic shift amount 4, 10 (CS # 4, 10) is set in each cluster of each antenna port (λ = 0, 1), and cluster # 1 has OCC # 1 is set, and OCC # 1 is set to cluster # 2. As shown in FIG. 16, in terminal # 2, cyclic shift amounts 10, 4 (CS # 10, 4) are set in each cluster of each antenna port (λ = 0, 1), and OCC is assigned to cluster # 1. # 2 is set, and OCC # 1 is set to cluster # 2.

FIG. 16 shows that the terminal # 1 and the terminal # 2 are orthogonal to each other because the OCC sequences are different for the cluster # 1, and MU-MIMO can be applied. On the other hand, since both the OCC sequence and the cyclic shift amount are the same for cluster # 2 shown in FIG. 16, the orthogonal relationship does not hold, and MU-MIMO cannot be applied. As described above, in setting example 3 (FIG. 14), depending on the setting of the cyclic shift amount for each terminal 200, a band to which MU-MIMO cannot be applied is generated. For this reason, there is a problem that the degree of freedom of frequency scheduling in MU-MIMO is reduced, and the scheduling gain by MU-MIMO is limited.

On the other hand, attention is focused on the OCC sequence of cluster # 1 in the usage sequence identification table shown in FIG. 15 (that is, the OCC sequence of the conventional usage sequence identification table (FIG. 4)). As shown in FIG. 15 (or FIG. 4), the OCC sequence of cluster # 1 is between cyclic shift amount information (cyclic shift amount information in the same pair) in which the cyclic shift amount used at the time of two antenna port transmission is the same. Different from each other. For example, when cyclic shift amount information = “000” (cyclic shift amount = 0, 6), antenna port numbers λ = 0 to 3 are [OCC # 1, OCC # 1, OCC # 2, OCC # 2] in this order. . On the other hand, when the cyclic shift amount information = '001' (cyclic shift amount = 6, 0), the antenna port numbers λ = 0 to 3 in the order [OCC # 2, OCC # 2, OCC # 1, OCC # 1. ].

Therefore, as described above, different OCC sequences are set for cluster # 1 and cluster # 2 or the same OCC sequence is set for each pair of cyclic shift information, which is the amount of cyclic shift used when transmitting two antenna ports. Thus, the OCC sequences are different from each other even in the cluster # 2 between the two pieces of cyclic shift amount information in the same pair.

As a result, in setting example 4, even when the cyclic shift amount information for the same cyclic shift amount used at the time of two-antenna port transmission is notified to different terminals 200, each terminal 200 receives the cluster # 1 and the cluster # 1. Different OCC sequences can be used in both of # 2. Therefore, in setting example 4, compared with setting example 3 (FIG. 14), the degree of freedom of frequency scheduling in MU-MIMO can be further improved, and the scheduling gain by MU-MIMO can be improved.

Similarly to setting example 3, the base station 100 uses the usage sequence identification table shown in FIG. 15 to, for example, transmit [OCC] to the terminal 200 that transmits at 2 antenna ports or less (λ = 0, 1). # 1, OCC # 1], [OCC # 1, OCC # 2], [OCC # 2, OCC # 1], and [OCC # 2, OCC # 2] are determined to be equally two each. It becomes possible. Therefore, as in setting example 3, base station 100 can improve the degree of freedom of frequency scheduling in MU-MIMO for terminal 200 transmitting at two antenna ports or less than setting example 2 (FIG. 13). This improves system throughput performance.

Similarly to setting example 2 (FIG. 13), the base station 100 uses the use sequence identification table shown in FIG. 14 to provide four different OCC patterns for a plurality of terminals 200 transmitting at three antenna ports or more. A combination of sequences (cyclic shift amount information = “011” to “110”) can be set. That is, base station 100 can improve the degree of freedom of frequency scheduling in MU-MIMO for terminal 200 that transmits with three or more antenna ports.

In the foregoing, the setting examples 1 to 4 of the use sequence identification table at the time of non-continuous band transmission have been described.

Thus, in the present embodiment, pattern candidates (cyclic shift amount information) representing combinations of OCC sequences of cluster # 1 and cluster # 2 in the used sequence identification table shared by base station 100 and terminal 200 are described. Among them, some pattern candidates have different OCC sequences between clusters, and pattern candidates other than the above-mentioned some pattern candidates have the same OCC sequences between clusters.

By doing so, the base station 100 can use all possible patterns as OCC sequence patterns that can be set in the cluster # 1 and the cluster # 2. Thereby, the base station 100 can set the OCC sequence used in DM-RS for the terminal 200 for each cluster. Therefore, base station 100 can set different OCC sequences for a plurality of terminals 200 even in the same transmission band, and can improve the degree of freedom of scheduling in MU-MIMO.

In addition, the base station 100 does not add a signaling bit for notifying the OCC sequence for DM-RS to the terminal 200 as compared with the conventional case (see, for example, FIG. 4). You can be notified.

Therefore, according to the present embodiment, the base station can set the OCC sequence used by the terminal for each cluster without increasing the number of signaling bits.

In setting example 3 in the above-described embodiment, “one cyclic shift” is selected from two pieces of cyclic shift amount information (pattern candidates) in which the patterns of the OCC sequences used in the plurality of antenna ports of cluster # 1 are the same. In the “quantity information”, the OCC sequences for the same antenna port are different from each other in the cluster # 1 and the cluster # 2, and in the “other cyclic shift amount information”, the OCC sequences for the same antenna port in the cluster # 1 and the cluster # 2. The case where they are the same has been described. On the other hand, which of the two pieces of cyclic shift amount information is the “one cyclic shift amount information” and which is the other cyclic shift amount information is determined based on setting example 4. May be. Specifically, “one cyclic shift amount information included in a part of a pair of pattern candidates among combinations of two cyclic shift sequences respectively used in each antenna port when two antenna ports are used. ", The OCC sequences for the same antenna port are different between the cluster # 1 and the cluster # 2, and the" other cyclic shift amount information "included in a pair other than the part of the pair described above, the cluster # 1 and the cluster # 2 The OCC sequences for the same antenna port may be the same. For example, in FIG. 4 (corresponding to the OCC sequence of cluster # 1 at the time of non-continuous band transmission), attention is paid to cyclic shift amount information '000', '001', '010', and '111'. Among these, the pattern of the OCC sequence used by the plurality of antenna ports of cluster # 1 is the same between “000” and “111” and between “001” and “010”. Become. Of these, between two “000” and “001”, and between “010” and “111”, two cyclic shift sequences respectively used in each antenna port when two antenna ports are used. The combination is the same. Here, “000” and “001” are called “pair A”, and “010” and “111” are called “pair B”. Therefore, here, among the two pieces of cyclic shift amount information (pattern candidates) in which the patterns of the OCC sequences used in the plurality of antenna ports of cluster # 1 are the same, the cyclic shift amount information included in “pair A” is Cluster # 1 and cluster # 2 have different OCC sequences for the same antenna port, and in the cyclic shift amount information included in “pair B”, cluster # 1 and cluster # 2 have the same OCC sequence for the same antenna port. You may make it become. That is, between “000” and “111”, different OCC sequences are set in cluster # 1 and cluster # 2 in “000” included in “pair A”, and “111” included in “pair B”. In ', the same OCC sequence is set in cluster # 1 and cluster # 2. The same applies between ‘010’ and ‘111’. The same applies to cyclic shift amount information “011”, “100”, “101”, and “110”. As a result, the use sequence identification table used in the base station 100 and the terminal 200 is the same as in setting example 4 (FIG. 15). As a result, the base station 100 and the terminal 200 using the use sequence identification table can obtain the same effects as those of the setting example 4.

In the above embodiment, the case where the use sequence specifying tables shown in FIGS. 11, 13, 14, and 15 are used at the time of non-continuous band transmission has been described. However, the usage sequence identification table described in the present embodiment (for example, FIG. 11, FIG. 13, FIG. 15, and FIG. 15) is used as the usage sequence identification table used at the time of non-continuous band transmission, or the same as in the prior art. Whether to use the use sequence identification table (for example, FIG. 4, that is, when the same OCC sequence is used in cluster # 1 and cluster # 2) may be switched for each terminal. For example, the case where the use sequence specifying table (FIG. 4) similar to the prior art is used is “pattern 1”, and the case where the use sequence specifying table shown in FIGS. 11, 13, 14, and 15 is used is “pattern 2”. And In this case, the base station may notify each terminal of “Pattern 1” or “Pattern 2” explicitly in advance by HigherHighlayer signaling. Alternatively, by associating the terminal IDs (odd and even) of each terminal with “Pattern 1” and “Pattern 2”, the base station assigns “Pattern 1” and “Pattern 2” to each terminal. May be notified.

For example, block diagrams showing configurations of the base station 300 and the terminal 400 in this case are shown in FIGS. 17 and 18, respectively. 17 and 18, the same components as those in the above-described embodiment (FIGS. 9 and 10) are denoted by the same reference numerals, and description thereof is omitted.

In the base station 300 shown in FIG. 17, the terminal information setting unit 301 sets which of the “pattern 1” and “pattern 2” the terminal 400 scheduled by the base station 300 uses. Terminal information setting section 301 outputs the set information (terminal information) to DM-RS information determination section 302. Note that the terminal information setting unit 301, for example, in the plurality of terminals 400 scheduled by the base station 300, the terminal 400 using “pattern 1” and the terminal 400 using “pattern 2” have an equal ratio. Each pattern may be set. At this time, the terminal information setting unit 301 may set each pattern in each terminal 400 at random.

The DM-RS information determination unit 302 generates a use sequence identification table used at the time of non-continuous band transmission of each terminal 400 based on the terminal information (“pattern 1” or “pattern 2”) input from the terminal information setting unit 301. to decide. Then, DM-RS information determination section 302 selects the cyclic shift amount and the OCC sequence number constituting DM-RS using the determined used sequence identification table in the same manner as in the above embodiment. DM-RS information determination section 302 then outputs the cyclic shift amount information associated with the selected cyclic shift amount and OCC sequence number to control information encoding section 101.

On the other hand, in terminal 400 shown in FIG. 18, terminal information setting section 401 uses DM-RS to indicate terminal information indicating whether terminal 400 scheduled by base station 300 uses “pattern 1” or “pattern 2”. The information is output to the information determination unit 402. As described above, whether the terminal 400 uses “Pattern 1” or “Pattern 2” may be notified explicitly from the base station 300 to the terminal 400, and notified to the Implicit using a terminal ID (fixed ID) or the like. May be.

The DM-RS information determination unit 402 determines the used sequence identification table used at the time of non-continuous band transmission based on the terminal information (“pattern 1” or “pattern 2”) input from the terminal information setting unit 401. Then, DM-RS information determination section 402 determines the cyclic shift amount and the OCC sequence number constituting the DM-RS using the determined used sequence identification table in the same manner as in the above embodiment. Then, DM-RS information determination section 402 outputs the determined cyclic shift amount and cyclic shift amount information associated with the OCC sequence number to DM-RS generation section 206.

In this way, the base station 300 varies the used sequence identification table at the time of discontinuous band transmission between the terminals 400 to be scheduled. For example, in FIG. 19, “pattern 1” is used for terminals 400 (terminals # 1 and # 2) with odd terminal IDs, and “pattern 2” is used for terminals 400 (terminal # 3) with even terminal IDs. Used. For example, in an environment where there are many terminals 400 in a cell covered by base station 300 (an environment where there are many terminal candidates to be scheduled), base station 300 is a terminal in which a pattern capable of orthogonalizing DM-RSs is set. Therefore, a plurality of terminals 400 may be scheduled so that terminals having similar reception qualities are MU-MIMO multiplexed. As a result, the frequency scheduling gain can be improved without increasing the signaling bits as in the above embodiment.

Also, in the above embodiment, whether the base station has set the “pattern 1” or “pattern 2” for the terminal other than the cyclic shift amount information included in the control information notified in the downlink channel Other parameters may be used for notification. The other parameter may be, for example, a cluster bandwidth, a cluster bandwidth position, or the like. For example, as shown in FIG. 20, when the cluster bandwidth (the number of RB (Resource Block) or the number of RBG (RB Group)) is an even number, “pattern 1” is associated with the cluster bandwidth (the number of RBGs). ) May be associated with an odd number and “pattern 2”. Note that RB is an allocation unit of frequency resources in LTE, and 1 RB = 180 kHz. Alternatively, “pattern # 1” is associated with the case where the leading RBG number of the cluster band position is an even number, and “pattern # 2” is associated with the case where the leading RBG number of the cluster band position is an odd number. Also good.

More specifically, the DM-RS information determination unit 114 (FIG. 9) of the base station 100 performs frequency resource allocation information (that is, the cluster bandwidth or the cluster bandwidth position) of each terminal 200 input from the scheduling unit 113. Based on the above, it is determined whether the terminal 200 scheduled by the base station 100 uses “Pattern 1” or “Pattern 2”. Then, the DM-RS information determination unit 114 selects the cyclic shift amount and the OCC sequence number constituting the DM-RS using the determined used sequence identification table in the same manner as in the above embodiment.

On the other hand, the DM-RS information determination unit 205 (FIG. 10) of the terminal 200 is based on the frequency resource allocation information (that is, the cluster bandwidth or the cluster band position) input from the control information decoding unit 204. 200 determines whether to use “Pattern 1” or “Pattern 2”. Then, DM-RS information determination section 205 determines the cyclic shift amount and OCC sequence number that constitute DM-RS, using the determined used sequence identification table, in the same manner as in the above embodiment.

Here, the cyclic shift amount information and the start position (RB. Start position (RB) of cluster # 1) of the frequency resource for transmitting the uplink signal are the response signal (ACK / NACK signal) from the terminal 200 to the downlink data signal. Is uniquely associated with a transmission resource (PHICH resource) of a control channel (PHICH: Physical HARQ Indicator Channel). For this reason, depending on the transmission band position between terminals 200 to which MU-MIMO is applied, a desired cyclic shift amount may not be set in order to prevent a PHICH resource collision. For this reason, a desired OCC sequence number is not set in terminal 200, and a transmission band to which MU-MIMO cannot be applied occurs.

On the other hand, here, since the OCC sequences of the cluster # 1 and the cluster # 2 are associated with parameters different from the cyclic shift amount information, a desired OCC sequence number cannot be set due to restrictions on the cyclic shift amount information. Can be reduced. Here, since the existing parameter is also used as a parameter for determining the used sequence identification table, the number of signaling bits does not increase.

Note that the parameter for determining the used sequence identification table is not limited to the frequency resource allocation information, and may be other information as long as it is a parameter notified from the base station to the terminal together with the cyclic shift amount information.

In the above embodiment, the case where the base station 100 and the terminal 200 hold the use sequence identification table for non-continuous band transmission has been described. However, the base station 100 and the terminal 200 are not limited to holding the used sequence identification table for non-continuous band transmission. For example, the base station 100 and the terminal 200 refer to the conventional table (see FIG. 4). The OCC sequence of cluster # 2 may be calculated according to the correspondence relationship with the sequence) and the sequence determination rules described in setting examples 1 to 4. Thereby, the base station 100 and the terminal 200 can set the OCC of the cluster # 2 without holding a table for determining the OCC of the cluster # 2.

Further, in the above embodiment, the use sequence identification table used at the time of non-continuous band transmission may be different for each cell. As a result, inter-sequence interference of reference signals (pilot signals) can be randomized (averaged) between cells.

In the above embodiment, the case where an OCC sequence is used in addition to a CS sequence as a sequence constituting a DM-RS has been described. However, the sequence constituting the DM-RS is not limited to the OCC sequence, and may be an orthogonal sequence or a highly orthogonal sequence. For example, a Walsh sequence may be used.

In the above embodiment, the control information notified in the downlink channel may be referred to as DCI (Downlink Control Information) or UL Grant.

In addition, the antenna port in the above embodiment refers to a logical antenna composed of one or a plurality of physical antennas. That is, the antenna port does not necessarily indicate one physical antenna, but may indicate an array antenna composed of a plurality of antennas.

For example, in 3GPP LTE, it is not defined how many physical antennas an antenna port is composed of, but is defined as a minimum unit by which a base station can transmit different reference signals (Reference signals).

Also, the antenna port may be defined as a minimum unit for multiplying the weight of a precoding vector (Precoding vector).

Further, although cases have been described with the above embodiment as examples where the present invention is configured by hardware, the present invention can also be realized by software in cooperation with hardware.

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

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

Furthermore, if integrated circuit technology that replaces LSI emerges as a result of advances in semiconductor technology or other derived technology, it is naturally also possible to integrate functional blocks using this technology. Biotechnology can be applied.

The disclosures of the specification, drawings and abstract contained in the Japanese application of Japanese Patent Application No. 2011-091086 filed on April 15, 2011 are incorporated herein by reference.

The radio communication apparatus and radio communication method according to the present invention can be applied to a mobile communication system such as LTE-Advanced.

100, 300 Base station 101 Control

information encoding unit

102, 208

Modulation unit

103, 212 Transmission unit 104, 201

Antenna port

105, 202 Reception unit 106 Reception processing unit 107

Separation unit

108, 110

DFT unit

109, 111 Demapping unit 112 Estimating unit 113

Scheduling unit

114, 205, 302, 402 DM-RS information determining unit 115 MIMO separating unit 116, 207 Data processing unit 117

IFFT unit

118, 203 Demodulating unit 119

Decoding unit

200, 400 Terminal 204 Control information decoding unit 206 DM RS generation unit 209 mapping unit 210 multiplexing unit 211 transmission weight multiplication unit 213 generation unit 214 arrangement unit

Claims

Generating means for generating a reference signal based on any one of a plurality of cyclic shift sequences separable from each other by different cyclic shift amounts according to a sequence determination rule and any one of a plurality of orthogonal sequences orthogonal to each other;
Transmitting means arranged in each of a plurality of clusters, for transmitting a transmission signal including the reference signal from at least one antenna port;
Comprising
The plurality of clusters includes a first cluster and a second cluster;
The sequence determination rule includes a plurality of patterns of a sequence including a first orthogonal sequence used at each antenna port in the first cluster and a second orthogonal sequence used at each antenna port in the second cluster. Including candidates,
Among the plurality of pattern candidates, in some pattern candidates, the first orthogonal sequence and the second orthogonal sequence for the same antenna port are different from each other, and in pattern candidates other than the some pattern candidates, the same antenna port The first orthogonal sequence and the second orthogonal sequence for
Transmitter device.
Each of the plurality of pattern candidates includes a cyclic shift sequence, the first orthogonal sequence, and the second orthogonal sequence,
Among the pattern candidate pairs in which the combination of two cyclic shift sequences used in each antenna port is the same when two antenna ports are used, the pattern candidates included in some of the pairs are the first for the same antenna port. The orthogonal sequence and the second orthogonal sequence are different from each other, and in the pattern candidates included in pairs other than the partial pair, the first orthogonal sequence and the second orthogonal sequence for the same antenna port are the same.
The transmission device according to claim 1.
In the series determination rule,
In the plurality of pattern candidates, one of the two pattern candidates in which the pattern of the first orthogonal sequence used in the plurality of antenna ports is the same, in one pattern candidate, the first orthogonal sequence for the same antenna port and the The second orthogonal sequence is different from each other, and in the other pattern candidate, the first orthogonal sequence and the second orthogonal sequence are the same.
The transmission device according to claim 1.
Each of the plurality of pattern candidates includes a cyclic shift sequence, the first orthogonal sequence, and the second orthogonal sequence,
When using two antenna ports, the one pattern candidate included in a part of the pair of pattern candidates in which the combination of two cyclic shift sequences respectively used in each antenna port is the same is used for the same antenna port. The first orthogonal sequence and the second orthogonal sequence are different from each other, and in the other pattern candidate included in a pair other than the partial pair, the first orthogonal sequence and the second orthogonal sequence for the same antenna port are Are the same,
The transmission device according to claim 3.
In the series determination rule,
Among the plurality of pattern candidates, the first orthogonal sequence is a pattern candidate that is the same for all antenna ports, and one of the two pattern candidates that has the same type of the first orthogonal sequence The first orthogonal sequence and the second orthogonal sequence for the same antenna port are different from each other, and in the other pattern candidate, the first orthogonal sequence and the second orthogonal sequence are the same.
The transmission device according to claim 1.
A reference generated based on any one of a plurality of cyclic shift sequences arranged in each of a plurality of clusters and separable from each other by different cyclic shift amounts, and any one of a plurality of orthogonal sequences orthogonal to each other Receiving means for receiving a signal including a signal;
Estimation means for estimating channel quality using a cyclic shift sequence and an orthogonal sequence determined according to a sequence determination rule, and the reference signal;
Comprising
The plurality of clusters includes a first cluster and a second cluster;
The sequence determination rule includes a plurality of patterns of a sequence including a first orthogonal sequence used at each antenna port in the first cluster and a second orthogonal sequence used at each antenna port in the second cluster. Including candidates,
Among the plurality of pattern candidates, in some pattern candidates, the first orthogonal sequence and the second orthogonal sequence for the same antenna port are different from each other, and in pattern candidates other than the some pattern candidates, the same antenna port The first orthogonal sequence and the second orthogonal sequence for
Receiver device.
Each of the plurality of pattern candidates includes a cyclic shift sequence, the first orthogonal sequence, and the second orthogonal sequence,
Among the pattern candidate pairs in which the combination of two cyclic shift sequences used in each antenna port is the same when two antenna ports are used, the pattern candidates included in some of the pairs are the first for the same antenna port. The orthogonal sequence and the second orthogonal sequence are different from each other, and in the pattern candidates included in pairs other than the partial pair, the first orthogonal sequence and the second orthogonal sequence for the same antenna port are the same.
The receiving device according to claim 6.
In the series determination rule,
In the plurality of pattern candidates, one of the two pattern candidates in which the pattern of the first orthogonal sequence used in the plurality of antenna ports is the same, in one pattern candidate, the first orthogonal sequence for the same antenna port and the The second orthogonal sequence is different from each other, and in the other pattern candidate, the first orthogonal sequence and the second orthogonal sequence are the same.
The receiving device according to claim 6.
Each of the plurality of pattern candidates includes a cyclic shift sequence, the first orthogonal sequence, and the second orthogonal sequence,
When using two antenna ports, the one pattern candidate included in a part of the pair of pattern candidates in which the combination of two cyclic shift sequences respectively used in each antenna port is the same is used for the same antenna port. The first orthogonal sequence and the second orthogonal sequence are different from each other, and in the other pattern candidate included in a pair other than the partial pair, the first orthogonal sequence and the second orthogonal sequence for the same antenna port are Are the same,
The receiving device according to claim 8.
In the series determination rule,
Among the plurality of pattern candidates, the first orthogonal sequence is a pattern candidate that is the same for all antenna ports, and one of the two pattern candidates that has the same type of the first orthogonal sequence The first orthogonal sequence and the second orthogonal sequence for the same antenna port are different from each other, and in the other pattern candidate, the first orthogonal sequence and the second orthogonal sequence are the same.
The receiving device according to claim 6.
A reference signal is generated based on any one of a plurality of cyclic shift sequences that are transmitted from at least one antenna port and can be separated from each other by different cyclic shift amounts, and any one of a plurality of orthogonal sequences orthogonal to each other A signal generation method for
In accordance with a sequence determination rule, determine a cyclic shift sequence and an orthogonal sequence used for the reference signal arranged in each of a plurality of clusters including the first cluster and the second cluster,
The sequence determination rule includes a plurality of patterns of a sequence including a first orthogonal sequence used at each antenna port in the first cluster and a second orthogonal sequence used at each antenna port in the second cluster. Including candidates,
Among the plurality of pattern candidates, in some pattern candidates, the first orthogonal sequence and the second orthogonal sequence for the same antenna port are different from each other, and in pattern candidates other than the some pattern candidates, the same antenna port The first orthogonal sequence and the second orthogonal sequence for
Signal generation method.
Reference generated based on any one of a plurality of cyclic shift sequences that can be separated from each other by different cyclic shift amounts and received by at least one antenna port, and any one of a plurality of orthogonal sequences orthogonal to each other A quality estimation method for estimating channel quality using a signal,
Using the cyclic shift sequence and the orthogonal sequence determined according to the sequence determination rule and the received reference signal, estimate the channel quality,
The plurality of clusters includes a first cluster and a second cluster;
The sequence determination rule includes a plurality of patterns of a sequence including a first orthogonal sequence used at each antenna port in the first cluster and a second orthogonal sequence used at each antenna port in the second cluster. Including candidates,
Among the plurality of pattern candidates, in some pattern candidates, the first orthogonal sequence and the second orthogonal sequence for the same antenna port are different from each other, and in pattern candidates other than the some pattern candidates, the same antenna port The first orthogonal sequence and the second orthogonal sequence for
Quality estimation method.