Radio communication apparatus and radio communication method

• US 8,369,285 B2
• Filed: 12/22/2008
• Issued: 02/05/2013
• 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: Nishio, Akihiko, Hiramatsu, Katsuhiko
• Primary Examiner(s): Kincaid, Lester
• Assistant Examiner(s): Khan, Mehmood B
• Application Number:
  US12/341,306
• Publication Number:
  US 20090104877A1
• Time in Patent Office: 1,506 Days
• Field of Search: 455/452, 455/522, 455/453, 455/512, 455/513, 370329-332
• US Class Current: 370/332
• 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 mobile device for receiving an orthogonal frequency division multiplexing (OFDM) signal, the mobile device comprising:

a reception section configured to receive information of a number from a base station, the information of the number corresponding to subcarrier blocks to be used for averaging channel quality, each of the subcarrier blocks including a plurality of subcarriers;

a subcarrier block selection section configured to select subcarrier blocks corresponding to the information of the number and providing preferred channel quality, within a communication band used for transmission from the base station to the mobile device, wherein said number is less than the total number of subcarrier blocks within the communication band and is determined correspondingly to the total number such that a first number is determined correspondingly to a smaller total number and a second number is determined correspondingly to a larger total number wherein the first number is smaller than the second number;

a CQI generating section configured to generate one channel quality indicator (CQI), the generated CQI being a value representing an average channel quality across only the selected subcarrier blocks; and

a reporting section configured to transmit a signal, to the base station, the signal including the generated CQI and information indicating positions of the selected subcarrier blocks selected by the subcarrier block selection section

wherein the information of the number received from the base station does not indicate positions of the subcarrier blocks to be selected.

2. The mobile device according to claim 1, wherein said number corresponding to subcarrier blocks to be used for averaging channel quality is determined correspondingly to the total number of subcarrier blocks within the communication band and an amount of traffic.

3. The mobile device according to claim 2, wherein said number corresponding to subcarrier blocks to be used for averaging channel quality is determined according to the following equation:

N_sb=└

N_all×

γ

₀/Σ

γ

_i┘

wherein N_all denotes the total number of subcarrier blocks within the communication band, γ

₀ denotes an amount of traffic in a cell that includes the mobile device, and γ

₀/Σ

γ

_i denotes a ratio of the amount of traffic in said cell to a total amount of traffic in said cell and neighboring cells.

4. A radio communication method to be carried out by a mobile device for receiving an orthogonal frequency division multiplexing (OFDM) signal, the radio communication method comprising:

receiving by said mobile device information of a number from a base station, the information of the number corresponding to subcarrier blocks to be used for averaging channel quality, each of the subcarrier blocks including a plurality of subcarriers, wherein the information of the number received from the base station does not indicate positions of the subcarrier blocks to be used;

selecting subcarrier blocks corresponding to the information of the number and providing preferred channel quality, within a communication band used for transmission from the base station to the mobile device, wherein said number is less than the total number of subcarrier blocks within the communication band and is determined correspondingly to the total number such that a first number is determined correspondingly to a smaller total number and a second number is determined correspondingly to a larger total number wherein the first number is smaller than the second number;

generating one channel quality indicator (CQI), the generated CQI being a value representing an average channel quality across only the selected subcarrier blocks; and

transmitting a signal, to the base station, the signal including the generated CQI and information indicating positions of the selected subcarrier blocks selected by the mobile device.

5. The radio communication method according to claim 4, wherein said number corresponding to subcarrier blocks to be used for averaging channel quality is determined correspondingly to the total number of subcarrier blocks within the communication band and an amount of traffic.

6. The radio communication method according to claim 5, wherein said number corresponding to subcarrier blocks to be used for averaging channel quality is determined according to the following equation:

N_sb=└

N_all×

γ

_o/Σ

γ

_i┘

wherein N_all denotes the total number of subcarrier blocks within the communication band, γ

₀ denotes an amount of traffic in a cell that includes the mobile device, and γ

₀/Σ

γ

_i denotes a ratio of the amount of traffic in said cell to a total amount of traffic in said cell and neighboring cells.