Wireless communications with efficient channel coding

• US 20030206561A1
• Filed: 02/05/2001
• Published: 11/06/2003
• Est. Priority Date: 06/09/2000
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Dabak, Anand G., Schmidl, Timothy M., Nafie, Mohammed
• Granted Patent: US 8,223,867 B2
• Time in Patent Office: Days
• US Class Current: 370/522
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0054 Maximum-likelihood or sequential decoding, e.g. Viterbi, Fano, ZJ algorithms
• CPC Class Codes: H04L 1/006 Trellis-coded modulation
• CPC Class Codes: H04L 1/1614 using bitmaps
• CPC Class Codes: H04L 1/1664 the supervisory signal being transmitted together with payload signals; piggybacking
• CPC Class Codes: H04L 1/1819 with retransmission of additional or different redundancy
• CPC Class Codes: H04L 1/1835 Buffer management
• CPC Class Codes: H04L 1/1874 Buffer management
• CPC Class Codes: H04L 1/188 Time-out mechanisms
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 24/06 Testing, supervising or monitoring using simulated traffic
• CPC Class Codes: H04W 28/04 Error control
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 28/22 Negotiating communication rate
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 84/10 Small scale networks; Flat hierarchical networks

Abstract

A data encoding algorithm can be used (120) to generate overhead bits from original data bits, and the original data bits and overhead bits can be transmitted in respectively separate transmissions (121, 123), if the overhead bits are needed. At the receiver, the original data bits can be determined (125) from the received overhead bits, or the received data bits and the received overhead bits can be combined and decoded together (126) to produce the original data bits.

Claims

1. A method of communicating data from a transmitting end to a receiving end, comprising:

the transmitting end applying to a plurality of original data bits that are to be transmitted to the receiving end an encoding algorithm that produces overhead bits;

the transmitting end transmitting the original data bits without the overhead bits in a first transmission to the receiving end; and

the transmitting end refraining from transmitting the overhead bits until the transmitting end receives an indication from the receiving end that the original data bits have not been correctly received at the receiving end.

2. The method of claim 1, including the transmitting end transmitting the overhead bits to the receiving end in a second transmission in response to an indication from the receiving end that the original data bits have not been correctly received at the receiving end.

3. The method of claim 2, including the receiving end combining a received version of the original data bits and a received version of the overhead bits to produce a combined set of received bits, and the receiving end applying to the combined set of received bits a decoding algorithm that corresponds to said encoding algorithm.

4. The method of claim 2, including the receiving end applying to a received version of the overhead bits a mapping operation which, if the overhead bits have been received correctly at the receiving end, will result in the original data bits, and the receiving end applying an error detection procedure to the result of the mapping operation to determine whether the mapping operation has resulted in the original data bits and, in response to a determination that the mapping operation has not resulted in the original data bits, the receiving end combining the received version of the overhead bits with a received version of the original data bits to produce a combined set of received bits, and the receiving end applying to the combined set of received bits a decoding algorithm that corresponds to said encoding algorithm.

5. The method of claim 4, wherein said encoding and decoding algorithms are Viterbi encoding and decoding algorithms.

6. The method of claim 4, including the receiving end applying an error detection procedure to a result of said decoding algorithm to determine whether said decoding algorithm has resulted in the original data bits and, in response to a determination that said decoding algorithm has not resulted in the original data bits, the receiving end transmitting to the transmitting end a request for retransmission of the original data bits.

7. The method of claim 6, including the transmitting end retransmitting the original data bits to the receiving end and, in response to a determination by the receiving end that said retransmission of the original data bits has not been received correctly, the receiving end combining a received version of the retransmitted original data bits with said received version of the overhead bits to produce another combined set of received bits, and the receiving end applying said decoding algorithm to said another combined set of received bits.

8. A method of communicating data from a transmitting end to a receiving end, comprising:

the receiving end receiving from the transmitting end a first transmission including original data bits;

the receiving end determining whether the original data bits have been received correctly and, responsive to a determination that the original data bits have not been received correctly, the receiving end transmitting to the transmitting end a request for transmission of overhead bits produced at the transmitting end by operation of an encoding algorithm applied to the original data bits.

9. The method of claim 8, wherein the encoding algorithm is a convolutional encoding algorithm.

10. A data communication apparatus, comprising:

an input for receiving original data bits that are to be transmitted via a communication channel to another data communication apparatus;

an encoder coupled to said input for applying to the original data bits an encoding algorithm that produces overhead bits;

an output for providing bits that are to be transmitted across the communication channel; and

a data path coupled between said encoder and said output for selectively providing to said output one of the original data bits and the overhead bits, said data path having a control input for receiving control information from said another communication apparatus, said data path responsive to said control information for selecting one of the original data bits and the overhead bits to be provided to said output for transmission across the communication channel to said another data communication apparatus.

11. The apparatus of claim 10, wherein said data path includes a buffer coupled to said encoder for storing the original data bits and the overhead bits.

12. The apparatus of claim 11, wherein said data path includes a selector coupled between said buffer and said output, said selector responsive to said control input for obtaining one of the original data bits and the overhead bits from said buffer to be provided to said output for transmission to said another data communication apparatus.

13. The apparatus of claim 10, wherein said control information includes a negative acknowledgement indicating that an earlier transmission has not been received correctly at said another communication apparatus, said data path responsive to the negative acknowledgement for changing its selection from one of the original data bits and the overhead bits to the other of the original data bits and the overhead bits.

14. The apparatus of claim 10, provided as a wireless communication apparatus.

15. The apparatus of claim 10, wherein said encoder is a convolutional encoder.

16. A data communication apparatus, comprising:

an input for receiving a received version of original bits transmitted over a communication channel by another data communication apparatus;

an error detector coupled to said input for determining whether the received version of the original data bits is correct; and

a controller coupled to said error detector and responsive to a determination that the received version of the original data bits is incorrect for providing for transmission to said another data communication apparatus a request for said another data communication apparatus to transmit overhead bits produced at said another data communication apparatus by operation of an encoding algorithm applied to the original bits.

17. The apparatus of claim 16, wherein said input is further for receiving a received version of the overhead bits as transmitted from said another data communication apparatus, said controller coupled to said input for applying to the received version of the overhead bits a mapping operation which, if the overhead bits have been received correctly at the receiving end, will result in the original data bits, said error detector coupled to said controller for applying an error detection procedure to the result of the mapping operation to determine whether the mapping operation has resulted in the original data bits.

18. The apparatus of claim 17, including a decoder coupled to said input and said controller, said controller responsive to a determination by said error detector that the mapping operation has not resulted in the original data bits for signaling said decoder to apply to the received version of the original data bits and the received version of the overhead bits a decoding algorithm that corresponds to said encoding algorithm.

19. The apparatus of claim 18, including a buffer coupled between said input and said decoder for storing the received version of the original bits and the received version of the overhead bits for use by said decoder.

20. The apparatus of claim 18, wherein said error detector is coupled to said decoder for determining whether said decoding algorithm has resulted in the original data bits, said controller operable in response to a determination that said decoding algorithm has not resulted in the original data bits for providing for transmission to said another data communication apparatus a request for retransmission of the original data bits.

21. The apparatus of claim 18, wherein said decoder is a Viterbi decoder.

22. The apparatus of claim 16, provided as a wireless communication apparatus.