Apparatus and method for decoding a received message with a priori information

• US 20070124654A1
• Filed: 11/30/2005
• Published: 05/31/2007
• Est. Priority Date: 11/30/2005
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola Mobility, Inc. (Lenovo Group Ltd.)
• Inventors: Buckley, Michael, Stewart, Kenneth, Smolinske, Jeffrey
• Granted Patent: US 7,730,385 B2
• Time in Patent Office: Days
• US Class Current: 714/786
• CPC Class Codes: H03M 13/3746 with iterative decoding
• CPC Class Codes: H03M 13/3994 using state pinning or decision forcing, i.e. the decoded sequence is forced through a particular trellis state or a particular set of trellis states or a particular decoded symbol
• CPC Class Codes: H03M 13/41 using the Viterbi algorithm or Viterbi processors
• CPC Class Codes: H03M 13/63 Joint error correction and other techniques H03M13/31 and H03M13/33 take precedence
• CPC Class Codes: H04L 1/0054 Maximum-likelihood or sequential decoding, e.g. Viterbi, Fano, ZJ algorithms
• CPC Class Codes: H04L 1/0057 Block codes H04L1/0061, H04L1/0064 take precedence
• CPC Class Codes: H04L 1/0059 Convolutional codes
• CPC Class Codes: H04L 1/0065 Serial concatenated codes
• CPC Class Codes: H04L 1/0072 Error control for data other than payload data, e.g. control data
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04L 1/201 Frame classification, e.g. bad, good or erased frame indication per se H04L1/0082

Abstract

An apparatus and method for receiving a message stream on a channel. A message is received on the channel. Information regarding the bits of a successfully decoded message is added to a message attributes list if the message is successfully decoded. An attempt is made to decode a subsequent message based on the information in the message attributes list.

Claims

1. A method of receiving a message stream, the method comprising:

receiving a message; and

attempting to decode the message based on information regarding the bits of a successfully decoded message stored in a message attributes list.

2. The method according to claim 1, wherein the information comprises a prototype message selected from a set of prototype messages, wherein the set of prototype messages is based on at least one previously decoded message.

3. The method according to claim 2, wherein the prototype message comprises upper layer information from a previously decoded message.

4. The method according to claim 2, wherein the prototype message comprises 168 bits of 224 bits of a previously received message.

5. The method according to claim 2, wherein attempting to decode the message further comprises replacing at least a portion of the output of a forward error correction decoder with the prototype message.

6. The method according to claim 2, wherein attempting to decode the message further comprises utilizing the prototype message to reduce the number of hypothesised forward error correction encoder states or forward error correction encoder codewords during forward error correction decoding.

7. The method according to claim 2, wherein attempting to decode the message further comprises utilizing a portion of the redundancy of an outer forward error correction code for error correction.

8. The method according to claim 1, wherein the information comprises statistical a priori knowledge of message bits in the received message identified from a previous successfully decoded message.

9. The method according to claim 8, wherein attempting to decode the message further comprises augmenting a metric calculation during a forward error correction decoding process wherein the information used to augment the metric calculation is based on at least one successfully decoded message drawn from a set of prototype messages.

10. The method according to claim 8 wherein a priori knowledge further comprises at least one selected from the group of the probability of selected bits of a message being a one or a zero, the probability of a bit of a message being a one or a zero based on a previously correctly decoded message, and the probability of a bit of a message being a one or a zero based on other related bits.

11. The method according to claim 1, further comprising adding information regarding the bits of a successfully decoded message to a message attributes list if the message is successfully decoded.

12. The method according to claim 1, wherein receiving a message further comprises receiving the message on a slow associated control channel.

13. A method of receiving a message stream on a control channel, the method comprising:

receiving a message on the control channel;

adding information regarding the bits of a successfully decoded message to a message attributes list if the message is successfully decoded; and

attempting to decode a subsequent message based on the information in the message attributes list.

14. The method according to claim 13, wherein the control channel is a slow associated control channel.

15. The method according to claim 13,

wherein the message attributes list comprises a message prototype list,

wherein adding information further comprises adding a prototype message decoded from the received message of the successfully decoded message to the message prototype list if the message is successfully decoded, and

wherein attempting to decode further comprises attempting to decode the subsequent message based on at least one prototype message stored in the message prototype list.

16. The method according to claim 15,

wherein the prototype message comprises an upper layer message, and

wherein attempting to decode further comprises:

detecting an error in decoding the subsequent message; and

if an error is detected, attempting to decode the subsequent message based on at least one prototype message stored in the message prototype list.

17. The method according to claim 16, wherein attempting to decode further comprises if an error is detected, replacing bits in the subsequent message with a prototype message stored in the message prototype list and attempting to decode the message based on the subsequent message with replaced bits.

18. A wireless communication device comprising:

a receiver configured to receive a message on a control channel;

a decoder coupled to the receiver, the decoder configured to decode the message;

a controller coupled to the decoder, the controller configured to control the operations of the wireless communication device;

a memory coupled to the controller, the memory including a message attribute list;

a list population module coupled to the controller, the list population module configured to add an attribute of a successfully decoded message to the message attribute list if the message is successfully decoded; and

wherein the decoder is further configured to attempt to decode a message based on an attribute in the message attribute list if there is an error decoding the message.

19. The wireless communication device according to claim 18, wherein the attribute comprises a prototype message based on the successfully decoded message.

20. The wireless communication device according to claim 19, wherein the prototype message comprises upper layer information from the successfully decoded message.

21. The wireless communication device according to claim 20, wherein the decoder is further configured to attempt to decode the message based on the message including bits replaced with the prototype message.

22. The wireless communication device according to claim 19, wherein the controller is further configured to utilize a portion of a redundancy of a Fire code for error correction of the received message.

23. The wireless communication device according to claim 18, wherein the attribute comprises statistical a priori knowledge of message bits in the received message identified from previous observations of the message stream.

24. The wireless communication device according to claim 18, wherein the receiver is further configured to receive the message on a slow associated control channel.