Wireless communication apparatus, wireless communication method, and wireless communication system

• US 9,571,244 B2
• Filed: 11/02/2012
• Issued: 02/14/2017
• Est. Priority Date: 01/26/2012
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Takano, Hiroaki
• Primary Examiner(s): Pham, Chi H
• Assistant Examiner(s): Agureyev, Vladislav
• Application Number:
  US14/372,855
• Publication Number:
  US 20150009924A1
• Time in Patent Office: 1,565 Days
• Field of Search: None
• 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 7/063 Parameters other than those covered in groups H04B7/0623 - H04B7/0634, e.g. channel matrix rank or transmit mode selection
• CPC Class Codes: H04B 7/0639 Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection
• CPC Class Codes: H04B 7/065 Variable contents, e.g. long-term or short-short
• CPC Class Codes: H04B 7/066 Combined feedback for a number of channels, e.g. over several subcarriers like in orthogonal frequency division multiplexing [OFDM]
• CPC Class Codes: H04L 5/0035 Resource allocation in a cooperative multipoint environment
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 72/563 of the wireless resources

Abstract

An overhead accompanying feedback from a UE terminal is reduced.

The UE terminal selects not only M subbands with high quality but also M subbands with poor quality. Alternatively, the UE terminal selects M subbands to be fed back by increasing a priority of a subband with a high degree to which the quality of the subband is to be improved by the feedback or a subband having a high possibility of unnecessary eNodeB being removed from the CoMP set by the feedback. In addition, the UE terminal performs measurement and feedback in units of subband groups which can be collectively handled.

Claims

1. A wireless communication apparatus comprising:

a reference signal measurement unit that performs measurement of reference signals transmitted from respective base stations in a wideband and respective subbands, under a communication environment in which an entire system bandwidth is used as the wideband and a plurality of subbands obtained by dividing the system bandwidth are used;

a measurement result selection unit that selects measurement results to be fed back in order to determine a cooperative group of the base stations which performs Coordinated Multi Point Transmission/Reception (CoMP) for its own apparatus, among measurement results obtained in the wideband and the respective subbands by the reference signal measurement unit; and

a feedback unit that feeds back the measurement results selected by the measurement result selection unit to the base station,

wherein the measurement result selection unit selects the measurement results to be fed back in order to determine the cooperative group, so as to include the measurement results of base stations other than the set of the measurement results in the respective subbands, in addition to the set of the measurement results of the base station in the wideband.

2. A wireless communication apparatus comprising:

a reference signal measurement unit that performs measurement of reference signals transmitted from respective base stations in a wideband and respective subbands, under a communication environment in which an entire system bandwidth is used as the wideband and a plurality of subbands obtained by dividing the system bandwidth are used;

a measurement result selection unit that selects measurement results to be fed back in order to determine a cooperative group of the base stations which performs Coordinated Multi Point Transmission/Reception (CoMP) for its own apparatus, among measurement results obtained in the wideband and the respective subbands by the reference signal measurement unit; and

a feedback unit that feeds back the measurement results selected by the measurement result selection unit to the base station,

the measurement result selection unit being configured to select the measurement results for feedback which avoid one or more predetermined feedback problems,

wherein the measurement result selection unit selects the measurement results such that an assembly of subbands which are consecutive in the frequency direction and have the same combination of the base stations constituting the cooperative group is made into a subband group and is fed back in units of subband groups.

3. A wireless communication apparatus comprising:

a notification unit that notifies a terminal station of information for determining a range for performing measurement and feedback of reference signals transmitted from respective base stations, under a communication environment in which an entire system bandwidth is used as a wideband and a plurality of subbands obtained by dividing the system bandwidth are used; and

a cooperative group determination unit that determines a cooperative group of base stations which performs CoMP for the terminal station in a wideband and the respective subbands, based on information which is fed back from the terminal station,

wherein the notification unit divides information notified to the terminal station into three types of information indicating a range having a possibility of being measured, information indicating a range which is used most widely, and information indicating a range of a base station which is additionally used for the respective subbands, and notifies the information in different update frequencies for each piece of information.

4. A wireless communication method comprising:

a notification step of notifying a terminal station of information for determining a range for performing measurement and feedback of reference signals transmitted from respective base stations, under a communication environment in which an entire system bandwidth is used as a wideband and a plurality of subbands obtained by dividing the system bandwidth are used; and

a cooperative group determination step of determining a cooperative group of base stations which performs CoMP for the terminal station in a wideband and the respective subbands, based on information which is fed back from the terminal station,

wherein the notification step includes dividing information notified to the terminal station into three types of information indicating a range having a possibility of being measured, information indicating a range which is used most widely, and information indicating a range of a base station which is additionally used for the respective subbands, and notifying the information in different update frequencies for each piece of information.