Terminal, base station, transmission method and reception method in a heterogeneous network regarding comp control of channel information

• US 9,325,475 B2
• Filed: 07/23/2012
• Issued: 04/26/2016
• Est. Priority Date: 08/05/2011
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Inventors: Hoshino, Masayuki, Suzuki, Hidetoshi, Nishio, Akihiko, Tamura, Takashi
• Primary Examiner(s): Zhao, Wei
• Assistant Examiner(s): Aung, Sai
• Application Number:
  US14/237,056
• Publication Number:
  US 20140161093A1
• Time in Patent Office: 1,373 Days
• Field of Search: 370/252, 370/315, 370/203
• US Class Current: 1/1
• CPC Class Codes: H04B 7/024 Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0031 Multiple signaling transmission H04L1/1664, F15 take precedence
• CPC Class Codes: H04L 1/1671 the supervisory signal being transmitted together with control information
• CPC Class Codes: H04L 5/0035 Resource allocation in a cooperative multipoint environment
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 52/146 Uplink power control
• CPC Class Codes: H04W 52/247 where the output power of a terminal is based on a path parameter sent by another terminal

Abstract

The present invention is a terminal capable of suppressing increase in transmit power required for transmitting a CSI report at a terminal while widely securing candidates for motion control. A reception processing unit (203) receives multiple reference signals from multiple transmission points, first information indicating the multiple transmission points, and second information indicating at least one transmission point included in the multiple transmission points; a CSI generation unit (206), on the basis of the first information, generates first channel information including channel information corresponding to each of the multiple reference signals from the multiple transmission points, and on the basis of the second information, generates second channel information including channel information corresponding to the reference signals from the at least one of the transmission points; and a transmission signal formation unit (208) transmits the first channel information and the second channel information which have been generated.

Claims

1. A terminal comprising:

a receiving section that receives a plurality of reference signals from a plurality of transmission points, first information indicating the plurality of transmission points and second information indicating at least one of some of the plurality of transmission points;

a generating section that generates a first channel state information (CSI) part including CSI respectively corresponding to the plurality of reference signals from the plurality of transmission points indicated by the first information and that generates a second CSI part including CSI corresponding to the reference signals from the some transmission points indicated by the second information, the first CSI part being used for updating the second information, and the second CSI part being used for control of coordinated transmission; and

a transmitting section that transmits the generated first CSI part and the generated second CSI part, wherein

the receiving section receives the first information through a radio resource control (RRC) signaling, and receives the second information through MAC control element (MAC CE);

the transmitting section transmits the first CSI part with lower frequency than a transmitting frequency of the second CSI part; and

the generated first CSI part includes a third CSI part corresponding to the reference signal from a transmission point not included in the some transmission points and a forth CSI part corresponding to the reference signal from the some transmission points, the third CSI part including wideband channel quality indicator (CQI) and not including precoding matrix indicator (PMI) and Rank indicator (RI), the forth CSI part including narrowband CQI, PMI and RI, and an amount of the third CSI part is smaller than an amount of the fourth CSI part.

2. The terminal according to claim 1, wherein information indicating the some transmission points is bit-map based information indicating which transmission points of the plurality of transmission points are the some transmission points.

3. The terminal according to claim 1, wherein one reference signal is configured for each of the plurality of transmission points.

4. The terminal according to claim 1, wherein a plurality of reference signals are configured for the one transmission point.

5. The terminal according to claim 1, wherein the some transmission points are a predetermined number of transmission points having better CSI among the plurality of transmission points.

6. The terminal according to claim 1, wherein the some transmission points are transmission points to be subjected to control of coordinated transmission by a plurality of transmission points among the plurality of transmission points.

7. The terminal according to claim 1, wherein the reference signals include at least a reference signal for demodulating a downlink control channel.

8. The terminal according to claim 1, wherein:

the second information is indicated using a predetermined indication region; and

the receiving section receives information indicating a transmission point which is a sender of a downlink control signal intended for the terminal in a region other than the region assigned the second information out in the indication region.

9. The terminal according to claim 1, further comprising an estimation section that estimates a path loss value using the second CSI part, wherein

the transmitting section transmits an uplink signal with transmission power configured based on the estimated path loss value.

10. The terminal according to claim 9, wherein the some transmission points are transmission points to be subjected to control of coordinated reception by a plurality of transmission points among the plurality of transmission points.

11. The terminal according to claim 9, wherein the transmission power is configured using an average value of a plurality of path loss values respectively corresponding to the some transmission points.

12. The terminal according to claim 9, wherein the transmission power is configured using a worst value of a plurality of path loss values respectively corresponding to the some transmission points.

13. The terminal according to claim 9, wherein the transmission power is configured using a best value of a plurality of path loss values respectively corresponding to the some transmission points.

14. The terminal according to claim 9, wherein the transmission power is configured using an intermediate value of a plurality of path loss values respectively corresponding to the some transmission points.

15. The terminal according to claim 9, wherein:

the transmission power is configured using a value obtained by multiplying the path loss value by a weighting factor; and

the weighting factor is increased as the number of the some transmission points increases.

16. The terminal according to claim 9, wherein the second CSI part used to configure the transmission power out of the path loss value respectively corresponding to the some transmission points differs depending on the type of the uplink signal.

17. The terminal according to claim 9, wherein:

the path loss value is estimated from the second CSI part and a parameter of a transmission point used as a reference for calculation of the path loss value;

the second information is indicated using a predetermined indication region; and

the receiving section receives information indicating the transmission point used as a reference in a region other than the region assigned the second information in the indication region.

18. The terminal according to claim 9, wherein:

the second information is indicated using a predetermined indication region; and

the receiving section receives information indicating a parameter used to configure the transmission power in a region other than the region assigned the second information in the indication region, and the parameter is set to a value corresponding to the transmission point used as a reference for a configuration of the transmission power.

19. A base station comprising:

a configuration section that configures a plurality of transmission points and at least one of some of the plurality of transmission points;

a transmitting section that transmits to a terminal, first information indicating the plurality of transmission points and second information indicating the some transmission points; and

a receiving section that receives a first channel state information (CSI) part including CSI respectively corresponding to a plurality of reference signals from the plurality of transmission points generated in the terminal based on the first information, and a second CSI part including CSI corresponding to reference signals from the some transmission points generated in the terminal based on the second information, the first CSI part being used for updating the second information, and the second CSI part being used for control of coordinated transmission, wherein

the transmitting section transmits the first information through a radio resource control (RRC) signaling, and transmits the second information through MAC control element (MAC CE);

the receiving section receives the first CSI part with lower frequency than a receiving frequency of the second CSI part; and

the received first CSI part includes a third CSI part corresponding to the reference signal from a transmission point not included in the some transmission points and a forth CSI part corresponding to the reference signal from the some transmission points, the third CSI part including wideband channel quality indicator (CQI) and not including precoding matrix indicator (PMI) and Rank indicator (RI), the forth CSI part including narrowband CQI, PMI and RI, and an amount of the third CSI part is smaller than an amount of the fourth CSI part.

20. A transmission method comprising:

receiving a plurality of reference signals from a plurality of transmission points;

receiving first information indicating the plurality of transmission points;

receiving second information indicating at least one of some of the plurality of transmission points;

generating a first channel state information (CSI) part including CSI respectively corresponding to the plurality of reference signals from the plurality of transmission points indicated by the first information and generating a second CSI part including CSI corresponding to the reference signals from the some transmission points indicated by the second information, the first CSI part being used for updating the second information, and the second CSI part being used for control of coordinated transmission; and

transmitting the generated first CSI part and the second CSI part, wherein

the first information is received through a radio resource control (RRC) signaling, and the second information is received through MAC control element (MAC CE);

the first CSI part is transmitted with lower frequency than a transmitting frequency of the second CSI part; and

the generated first CSI part includes a third CSI part corresponding to the reference signal from a transmission point not included in the some transmission points and a forth CSI part corresponding to the reference signal from the some transmission points, the third CSI part including wideband channel quality indicator (CQI) and not including precoding matrix indicator (PMI) and Rank indicator (RI), the forth CSI part including narrowband CQI, PMI and RI, and an amount of the third CSI part is smaller than an amount of the fourth CSI part.

21. A reception method comprising:

configuring a plurality of transmission points and transmitting first information indicating the plurality of transmission points to a terminal;

receiving a first channel state information (CSI) part including CSI respectively corresponding to a plurality of reference signals from the plurality of transmission points generated in the terminal based on the first information;

configuring at least one of some of the plurality of transmission points and transmitting second information indicating the some transmission points to the terminal; and

receiving a second CSI part including CSI corresponding to reference signals from the some transmission points generated in the terminal based on the second information, the first CSI part being used for updating the second information, and the second CSI part being used for control of coordinated transmission, wherein

the first information is transmitted through a radio resource control (RRC) signaling, and the second information is transmitted through MAC control element (MAC CE);

the first CSI part is received with lower frequency than a receiving frequency of the second CSI part; and

the received first CSI part includes a third CSI part corresponding to the reference signal from a transmission point not included in the some transmission points and a forth CSI part corresponding to the reference signal from the some transmission points, the third CSI part including wideband channel quality indicator (CQI) and not including precoding matrix indicator (PMI) and Rank indicator (RI), the forth CSI part including narrowband CQI, PMI and RI, and an amount of the third CSI part is smaller than an amount of the fourth CSI part.