CODE RATE ADAPTATION IN WIRELESS COMMUNICATION SYSTEMS

• US 20140045507A1
• Filed: 08/07/2012
• Published: 02/13/2014
• Est. Priority Date: 08/07/2012
• Status: Abandoned Application

• Current Assignee: Blackberry Limited
• Original Assignee: Blackberry Limited
• Inventors: Bontu, Chandra Sekhar, Song, Yi, Cai, Zhijun
• Application Number:
  US13/569,072
• Publication Number:
  US 20140045507A1
• Time in Patent Office: Days
• US Class Current: 455/450
• 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 1/0073 Special arrangements for feedback channel
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 5/0055 Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04L 5/0094 Indication of how sub-channels of the path are allocated
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management

Abstract

Systems, methods, and apparatuses for transmitting physical hybrid automatic repetition request indicator channel (PHICH) signals using adaptive code rates are provided. In accordance with one implementation, various PHICH code rates may be supported by configuring a different number of resource element groups (REGs) to transmit the PHICH signal. The information regarding the REGs may be transmitted to a user equipment (UE) in a radio resource control (RRC) message or in an uplink grant message or in a medium access control (MAC) control element. Correspondingly, the UE may detect the PHICH signal with adaptive code rate on the indicated REGs. Furthermore, channel state information (CSI) may be transmitted from the UE to a base station to indicate the measured PHICH quality, such that the base station may determine appropriate PHICH code rate for the UE based on the CSI information.

Claims

1. A method for wireless communication, comprising:

transmitting a first Physical Hybrid Automatic Repeat Request (HARQ) Indicator Channel (PHICH) signal using a first coding rate; and

transmitting a second PHICH signal using a second coding rate, the second coding rate being different from the first coding rate.

2. The method of claim 1, wherein the first and second PHICH signals are transmitted on one or more Resource Element Groups (REGs).

3. The method of claim 2, wherein information regarding the one or more REGs is transmitted in a Radio Resource Control (RRC) message.

4. The method of claim 3, wherein the information is represented by one or more bit maps.

5. The method of claim 2, wherein the one or more REGs used to transmit the first PHICH signal is different from the one or more REGs used to transmit the second PHICH signal.

6. The method of claim 2, wherein information regarding the one or more REGs is transmitted in an uplink resource grant message.

7. The method of claim 6, wherein the uplink resource grant message is transmitted using at least one of Downlink Control Information (DCI) format 0 or DCI format 4.

8. The method of claim 6, wherein the information is represented by one or more bit maps.

9. The method of claim 1, wherein the first and second PHICH signals are transmitted using a repetition code.

10. The method of claim 1, further comprising:

receiving first and second channel state information (CSI) from first and second user equipments, respectively; and

determining the first and second coding rate based on the received CSI.

11. The method of claim 10, wherein the first and second CSI are measured based on received signal qualities of physical downlink shared channels (PDSCH) at the user equipments.

12. The method of claim 10, wherein the first and second CSI are measured based on received signal qualities of prior transmitted PHICH signals at the user equipments.

13. A base station configured to:

transmit a first Physical Hybrid Automatic Repeat Request (HARQ) Indicator Channel (PHICH) signal using a first coding rate; and

transmit a second PHICH signal using a second coding rate, the second coding rate being different from the first coding rate.

14. The base station of claim 13, wherein the first and second PHICH signals are transmitted on one or more Resource Element Groups (REGs).

15. The base station of claim 14, wherein information regarding the one or more REGs is transmitted in a Radio Resource Control (RRC) message.

16. The base station of claim 15, wherein the information is represented by one or more bit maps.

17. The base station of claim 14, wherein the one or more REGs used to transmit the first PHICH signal is different from the one or more REGs used to transmit the second PHICH signal.

18. The base station of claim 14, wherein information regarding the one or more REGs is transmitted in an uplink resource grant message.

19. The base station of claim 18, wherein the uplink resource grant message is transmitted using at least one of Downlink Control Information (DCI) format 0 or DCI format 4.

20. The base station of claim 18, wherein the information is represented by one or more bit maps.

21. The base station of claim 13, wherein the first and second PHICH signals are transmitted using a repetition code.

22. The base station of claim 13, further configured to:

receive first and second channel state information (CSI) from first and second user equipments, respectively; and

determine the first and second coding rate based on the received CSI.

23. The base station of claim 22, wherein the first and second CSI are measured based on received signal qualities of physical downlink shared channels (PDSCH) at the user equipments.

24. The base station of claim 22, wherein the first and second CSI are measured based on received signal qualities of prior transmitted PHICH signals at the user equipments.