Method to utilize physical layer channel state information to improve video quality

• US 20080025204A1
• Filed: 03/16/2007
• Published: 01/31/2008
• Est. Priority Date: 03/17/2006
• Status: Abandoned Application

• Current Assignee: The Board of Trustees of Michigan State University (Michigan State University)
• Original Assignee: The Board of Trustees of Michigan State University (Michigan State University)
• Inventors: Parrikar, Utpal, Misra, Kiran, Karande, Shirish, Radha, Hayder
• Application Number:
  US11/725,242
• Publication Number:
  US 20080025204A1
• Time in Patent Office: Days
• US Class Current: 370/216
• CPC Class Codes: H03M 13/1111 Soft-decision decoding, e.g. by means of message passing or belief propagation algorithms
• CPC Class Codes: H03M 13/612 Aspects specific to channel or signal-to-noise ratio estimation H03M13/63 takes precedence
• CPC Class Codes: H03M 13/6527 IEEE 802.11 [WLAN]
• CPC Class Codes: H04L 1/0045 Arrangements at the receiver end
• CPC Class Codes: H04N 19/61 in combination with predictive coding

Abstract

A method is provided for improving error recovery of corrupt data packets in a wireless communication system. The method includes: receiving a plurality of incoming data packets over a wireless medium at a receiver; capturing an indicator of bit errors for each of the data packets at a layer of the receiver below an application layer; passing the bit error indicator for each of the data packets to the application layer of the receiver; and performing an error recovery operation in relation to a given data packet at the application layer using the bit error indicator associated with the given data packet.

Claims

1. A method for improving error recovery of corrupt data packets in a wireless communication system, comprising:

receiving a plurality of incoming data packets over a wireless medium at a physical layer of a receiver;

capturing an indicator of bit errors for each of the data packets at a layer of the receiver below an application layer as defined by an Open System Interconnection (OSI) model;

passing the bit error indicator for each of the data packets to the application layer of the receiver; and

performing an error recovery operation in relation to a given data packet at the application layer using the bit error indicator associated with the given data packet.

2. The method of claim 1 wherein the indicator of bits errors is reported by a communication protocol operating at a data link layer of the receiver.

3. The method of claim 1 wherein the communication protocol is further defined in accordance with the 802.11x standard.

4. The method of claim 1 wherein capturing an indicator further comprises receiving a signal to silence ratio for each data packet as reported in accordance with the 802.11b standard.

5. The method of claim 1 wherein the error recovery operation is further defined as a forward error correction scheme.

6. The method of claim 1 wherein performing an error recovery operation further comprises decoding bits of the given data packet using a low density parity check decoding scheme.

7. The method of claim 6 further comprises decoding bits of the given data packet using a log-likelihood ratio, where a bit error probability for the given data packet is derived from the passed bit error indicator.

8. The method of claim 1 further comprises determining whether each data packet contains errors prior to passing the bit error indicator and forwarding data packets without errors to the application layer without passing the bit error indicator for the data packets.

9. The method of claim 8 wherein determining whether each data packet contains errors further comprises determining whether errors are found in a header of the data packet and dropping data packets having errors in the header of the data packet.

10. The method of claim 8 wherein determining whether each data packet contains errors further comprises determining whether errors are found in a header of the data packet and passing the bit error indicator to the application layer for data packets having errors outside of the header of the data packet.

11. A method for improving error recovery of corrupt data packets in a wireless communication system, comprising:

receiving an indicator of bit errors for a given data packet at an application layer of a receiver;

translating the indicator of bit error to a bit error probability for the given data packet; and

decoding each bit in the given data packet using the bit error probability for the given data packet.

12. The method of claim 11 wherein the indicator of bits errors is a signal to silence ratio as reported by a communication protocol operating at a data link layer of the receiver.

13. The method of claim 11 wherein decoding each bit further comprises decoding each bit using a low density parity check decoding scheme.

14. The method of claim 13 further comprises decoding bits of the given data packet using a log-likelihood ratio, where a bit error probability for the given data packet is derived from the passed bit error indicator.

15. A method for improving error recovery of corrupt data packets in a wireless communication system, comprising:

receiving a plurality of incoming data packets over a wireless medium at a physical layer of a receiver, wherein the data is encoded in accordance with a forward error correction scheme;

capturing an indicator of bit errors for each of the data packets at a layer other than an application layer of the receiver;

passing the bit error indicator for each of the data packets to the application layer of the receiver; and

decoding each of the data packets at the application layer using the bit error indicator associated with the given data packet.

16. The method of claim 15 wherein the indicator of bits errors is reported by a communication protocol operating at a data link layer of the receiver.

17. The method of claim 15 wherein capturing an indicator further comprises receiving a signal to silence ratio for each data packet as reported in accordance with the 802.11b standard.

18. The method of claim 15 further comprises decoding data packets using a low density parity check decoding scheme.

19. The method of claim 18 further comprises decoding bits of a given data packet using a log-likelihood ratio, where a bit error probability for the given data packet is derived from a signal to silence ratio for each data packet as reported in accordance with the 802.11b standard.

20. The method of claim 19 further comprises deriving the bit error probability for a given data packet using an empirical relationship with the signal to silence ratio.

21. A method for improving error recovery of corrupt data packets in a wireless communication system, comprising:

receiving an incoming data packet over a wireless medium at a receiver;

determining if the data packet is error free;

forwarding the data packet to an application layer of the receiver when the data packet is error free;

determining an indicator of bit errors associated with data packet at a layer of the receiver below an application layer as defined by an Open System Interconnection (OSI) model when the data packet contains errors;

forwarding the data packet along with the bit error indicator for the data packet to the application layer; and

performing an error recovery operation in relation to the data packet at the application layer using the bit error indicator associated with the data packet.

23. The method of claim 21 wherein the indicator of bits errors is reported by a communication protocol operating at a data link layer of the receiver.

24. The method of claim 21 wherein determining an indicator of bit errors further comprises receiving a signal to silence ratio for the data packet as reported in accordance with the 802.11b standard.

25. The method of claim 21 wherein the error recovery operation is further defined as a forward error correction scheme.

26. The method of claim 21 wherein performing an error recovery operation further comprises decoding bits of the data packet using a low density parity check decoding scheme.

27. The method of claim 26 further comprises decoding bits of the data packet using a log-likelihood ratio, where a bit error probability for the data packet is derived from the passed bit error indicator.

22. The method of 21 further comprises determining if the errors occur in a header of the data packet when the data packet contains errors and dropping the data packet when the header contains errors.