Radio communication apparatus and radio communication method

• US 20060089102A1
• Filed: 11/20/2003
• Published: 04/27/2006
• Est. Priority Date: 12/26/2002
• Status: Active Grant

• Current Assignee: Optis Wireless Technology, LLC (Brevet Capital)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Hiramatsu, Katsuhiko, Nishio, Akihiko
• Granted Patent: US 8,254,335 B2
• Time in Patent Office: Days
• US Class Current: 455/67.110
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0021 in which the algorithm uses adaptive thresholds
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04L 5/0094 Indication of how sub-channels of the path are allocated
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports

Abstract

A CIR measuring section 307 measures CIRs of all blocks received and a block selection section 308 makes a threshold decision based on the CIR measurement result and threshold information according to an amount of traffic in the own cell and neighboring cells. As a result of the threshold decision, blocks whose CIRs exceed the threshold are regarded as usable blocks. A CIR averaging section 309 averages the CIRs of the usable blocks and a CQI generation section 310 generates a CQI based on the CIR average value. The CQI generated and selected block numbers are reported to a base station apparatus. This allows the throughput of the own cell and neighboring cells to be improved.

Claims

1. A radio communication apparatus comprising:

a reception section that receives an OFDM signal;

a reception quality measuring section that demodulates the received OFDM signal and measures reception quality of each subcarrier;

a subcarrier selection section that selects subcarriers having top-ranking reception quality as subcarriers to be used based on a criterion notified from the other party of communication;

an averaging section that averages the reception quality of the subcarriers selected by said subcarrier selection section; and

a reporting section that generates a report value indicating the reception quality averaged by said averaging section and reports the report value generated and information indicating the subcarriers selected by said subcarrier selection section to the other party of communication.

2. The radio communication apparatus according to claim 1, wherein said subcarrier selection section selects subcarriers of reception quality equal to or higher than a threshold as subcarriers to be used based on reception quality and a threshold decision against a threshold notified from the other party of communication.

3. The radio communication apparatus according to claim 2, wherein said threshold is controlled adaptively according to an amount of traffic in the own cell and neighboring cells.

4. The radio communication apparatus according to claim 1, wherein said subcarrier selection section selects the same number of subcarriers as that notified from the other party of communication.

5. The radio communication apparatus according to claim 4, wherein said number of subcarriers is controlled adaptively according to an amount of traffic in the own cell and neighboring cells.

6. The radio communication apparatus according to claim 2, wherein said subcarrier selection section selects subcarriers to be used from among the subcarriers restricted beforehand out of all subcarriers.

7. A communication terminal apparatus comprising the radio communication apparatus according to claim 1.

8. A radio communication method comprising the steps of:

selecting subcarriers having top-ranking reception quality as subcarriers to be used based on a criterion notified from the other party of communication;

generating a report value indicating average reception quality of the selected subcarriers; and

reporting the report value generated and information indicating the selected subcarriers to the other party of communication.

9. A radio communication system comprising:

a base station apparatus that sends information which becomes a selection criterion of subcarriers according to an amount of traffic in the own cell and neighboring cells to a communication terminal apparatus; and

a communication terminal apparatus that selects subcarriers having top-ranking reception quality as subcarriers to be used based on selection criterion information sent from said base station apparatus and reception quality of each subcarrier, and reports a report value indicating average reception quality of the selected subcarriers and information indicating the selected subcarriers to said base station apparatus.