RADIO COMMUNICATION SYSTEM, RADIO TRANSMISSION APPARATUS, AND RETRANSMISSION METHOD

• US 20090168711A1
• Filed: 03/20/2007
• Published: 07/02/2009
• Est. Priority Date: 03/20/2006
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Nishio, Akihiko, Fukuoka, Masaru, Miyoshi, Kenichi
• Granted Patent: US 8,774,107 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0027 Scheduling of signalling, e.g. occurrence thereof
• CPC Class Codes: H04L 1/1825 Adaptation of specific ARQ protocol parameters according to transmission conditions
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/1893 Physical mapping arrangements physical resource mapping in general H04L5/00
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04L 5/0032 Distributed allocation, i.e. involving a plurality of allocating devices, each making partial allocation
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04W 28/04 Error control
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

Provided is a retransmission method capable of improving reception quality in retransmission control. In this method, for the first transmission, LRB (Localized Resource Block) method is selected as a resource allocation method according to the CQI fed back from the mobile station. A frequency resource having the best reception quality according to the LRB format is allocated for the transmission data. For the second transmission, the same resource allocation method (LRB) as the first transmission is used and the transmission data is allocated fro the same frequency resource. For the third transmission, the resource allocation method is switched from the method of the first and the second transmission and transmission data is allocated to the frequency resource by using DRB (Distributed Resource Block) format.

Claims

1. A radio communication system comprising:

a selecting section that selects a localized resource block scheme or a distributed resource block scheme as a resource allocation scheme; and

an allocating section that allocates transmission data to frequency resources according to the selected resource allocation scheme,

wherein, when identical transmission data is transmitted several times, the selecting section switches the resource allocation scheme from the localized resource block scheme to the distributed resource block scheme upon transmission except a first transmission.

2. A radio transmitting apparatus comprising:

a selecting section that selects a localized resource block scheme or a distributed resource block scheme as a resource allocation scheme; and

an allocating section that allocates transmission data to frequency resources according to the selected resource allocation scheme,

wherein, when identical transmission data is transmitted several times, the selecting section switches the resource allocation scheme from the localized resource block scheme to the distributed resource block scheme upon transmission except a first transmission.

3. The radio transmitting apparatus according to claim 2, further comprising a modulating section that changes a modulation scheme for the transmission data in synchronization with switching by the selecting section, of the resource allocation scheme from the localized resource block scheme to the distributed resource block scheme.

4. The radio transmitting apparatus according to claim 2, wherein the allocating section distributes the frequency resources in a greater range when a number of transmissions increases upon transmission in the distributed resource block scheme.

5. The radio transmitting apparatus according to claim 2, wherein the allocating section makes the frequency resources to which the transmission data is allocated, different between transmissions upon transmission in the distributed resource block scheme.

6. The radio transmitting apparatus according to claim 2, wherein the selecting section determines a timing for switching the resource allocation scheme from the localized resource block scheme to the distributed resource block scheme based on a modulation scheme and coding rate of the transmission data.

7. The radio transmitting apparatus according to claim 6, wherein the selecting section sets an earlier timing for switching transmission data in the same modulation scheme when the coding rate is lower.

8. The radio transmitting apparatus according to claim 2, wherein the selecting section determines a timing for switching the resource allocation scheme from the localized resource block scheme to the distributed resource block scheme based on a delay time from a timing of receiving a channel quality indicator from a radio receiving apparatus.

9. The radio transmitting apparatus according to claim 2, wherein the selecting section determines a timing for switching the resource allocation scheme from the localized resource block scheme to the distributed resource block scheme based on a moving speed of a radio receiving apparatus.

10. The radio transmitting apparatus according to claim 2, further comprising a reporting section that reports a timing for switching the resource allocation scheme from the localized resource block scheme to the distributed resource block scheme to a radio receiving apparatus upon a first transmission of the transmission data.

11. The radio transmitting apparatus according to claim 2, further comprising:

a table that stores a plurality of resource allocation methods of the localized resource block scheme and a plurality of resource allocation methods of the distributed resource block scheme associated with each other one-on-one and that is common between a transmission side and a reception side; and

a reporting section that reports to a radio receiving apparatus a resource allocation method to be actually used out of the plurality of resource allocation methods of the localized resource block scheme.

12. The radio transmitting apparatus according to claim 2, wherein the selecting section switches the resource allocation scheme from the localized resource block scheme to the distributed resource block scheme when there is a switching request from a radio receiving apparatus.

13. The radio transmitting apparatus according to claim 12, wherein the selecting section determines that there is the switching request when a channel quality indicator is fed back from the radio receiving apparatus at a predetermined timing.

14. A communication terminal apparatus comprising the radio transmitting apparatus according to claim 2.

15. A base station apparatus comprising the radio transmitting apparatus according to claim 2.

16. A retransmission method comprising, when identical transmission data is transmitted several times, switching a resource allocation scheme for the transmission data from a localized resource block scheme to a distributed resource block scheme upon transmission except a first transmission.