Transmission frame structure for a satellite digital audio radio system

• US 6,618,367 B1
• Filed: 12/16/1999
• Issued: 09/09/2003
• Est. Priority Date: 12/16/1999
• Status: Expired due to Term

• Current Assignee: Infineon Technologies AG
• Original Assignee: Agere Systems Incorporated (Broadcom, Inc.)
• Inventors: Zheng, Dunmin, Sayeed, Zulfiquar, Riazi, Habib
• Primary Examiner(s): VO, NGUYEN THANH
• Application Number:
  US09/464,574
• Time in Patent Office: 1,363 Days
• Field of Search: 375/260, 714/786, 714/FOR.102, 714/FOR.104, 714/784, 714/746, 714/752, 714/756, 714/776, 370/336, 370/337, 370/347, 370/208
• US Class Current: 370/347
• CPC Class Codes: H04H 40/90 specially adapted for satellite broadcast receiving

Abstract

A satellite digital audio radio system (SDARS) transmitter provides a broadcast transmission signal including a time division multiplex (TDM) mode of transmission and a coded orthogonal frequency multiplex (OFDM) mode of transmission. The SDARS transmitter provides a transmission signal that supports four transport mechanisms or traffic channels: (1) multiple audio and data program channels (program channels), (2) a cluster control information channel (CC), (3) a global control information channel (GC), and (4) a synchronization channel (CS). In particular, the SDARS transmitter processes 100 program channels into 5 clusters, each cluster comprising GC and CS information, along with a program cluster comprising 20 program channels and CC information. The SDARS transmitter further partitions each cluster into 255 cluster segments and interleaves the cluster segments from each cluster for transmission.

Claims

1. A method for use in a transmitter, the method comprising the steps of:

processing N program channels into M clusters, each cluster representing at least k program channels, where M>

1, k>

1, N>

M, and (k)(M)≦

N;

partitioning each cluster into at least J cluster segments; and

forming a transmission frame by interleaving the at least J cluster segments from each cluster for transmission, where J>

1.

2. The method of claim 1, wherein each cluster segment comprises at least some synchronization information, some global control information and a program cluster segment of a program cluster, wherein the program cluster represents the at least k program channels for that cluster and cluster control information.

3. The method of claim 2, wherein each program cluster comprises two cluster control fields and an audio-encoded field for the at least k programs.

4. The method of claim 3, wherein the two cluster control fields are duplicates of each other.

5. The method of claim 3, wherein the audio-encoded field comprises a fixed number of audio-encoded data bits, J, and each program of the at least k programs represents a fixed number of audio-encoded data bits that is smaller than J.

6. The method of claim 3, wherein the audio-encoded field comprises a fixed number of audio-encoded data bits, J, and each program of the at least k programs represents a variable number of audio-encoded data bits such that a sum of the audio-encoded data bits for all of the at least k programs is no larger than J.

7. The method of claim 1 wherein the processing step includes the following steps, in no particular order:

(a) providing, for each of the M clusters, an encoded global control information field;

(b) providing, for each of the M clusters, an audio-encoded portion of a program cluster for the at least k program channels; and

(c) providing, for each of the M clusters, cluster synchronization information.

8. The method of claim 7 wherein step (a) includes the step of using a concatenation of a block code and a convolutional code to provide the encoded global information field.

9. The method of claim 8 wherein the block code is a Reed-Solomon (58,40,8) code and the convolutional code is a rate 1/7 code.

10. The method of claim 7 wherein step (b) includes the step of using a concatenation of a block code and a convolutional code to provide the audio-encoded portion of the program cluster for the at least k channels.

11. The method of claim 10 wherein the block code is a Reed-Solomon (128,117,8) code and the convolutional code is a rate 2/3 code.

12. The method of claim 7, wherein each program cluster further comprises two cluster control fields.

13. The method of claim 12 further comprising the step of providing for each of the two cluster control fields encoded cluster control information.

14. The method of claim 13 further including the step of using a concatenation of a block code and a convolutional code to provide the encoded cluster control information.

15. The method of claim 14 wherein the block code is a Reed-Solomon (105,40,8) code and the convolutional code is a rate 1/3 code.

16. The method of claim 12 wherein the two cluster control fields are duplicates of each other.

17. The method of claim 7 wherein the cluster synchronization information is identical for each cluster.

18. The method of claim 17 wherein the cluster synchronization information is represented by a maximal length PN (pseudo-random number) sequence.

19. The method of claim 7 wherein steps (a) and (b) provide different levels of error protection for the encoded global control information and the audio-encoded program cluster.

20. The method of claim 1 further comprising the step of transmitting the transmission frame using time division multiplexing (TDM) and orthogonal frequency division multiplexing (OFDM).

21. The method of claim 19 wherein each cluster segment is equal in width to an OFDM symbol.

22. The method of claim 19 wherein for TDM, a training sequence is inserted before each cluster segment.

23. A transmission frame representing data embodied in a transmission signal having a center frequency and at least one carrier wave, the transmission frame comprising:

an interleaved sequence of cluster segments, the cluster segments taken from M clusters of data, each cluster of data comprising J cluster segments, where M>

1 and J>

1;

wherein each cluster segment of a respective cluster comprises;

a cluster synchronization field;

a global information field; and

a program cluster segment of a program cluster, wherein the program cluster represents at least k program channels, where k>

1, and cluster control information.

24. A transmission frame representing data embodied in a transmission signal having a center frequency and at least one carrier wave, the transmission frame comprising:

an interleaved sequence of cluster segments, the cluster segments taken from M clusters of data, each cluster of data comprising J cluster segments, where M>

1 and J>

1;

wherein each cluster segment of a respective cluster comprises;

a cluster channel synchronization field comprising at least c bits taken from a (J)(c) bit cluster synchronization word not larger than (J)(c) bits;

a global channel information field comprising a g bits taken from a global channel information word not larger than (J)(g) bits; and

a program cluster segment of a program cluster, wherein the program cluster represents at least k program channels, where k>

1, and two fields of cluster control information which are duplicates of each other.

25. A transmission frame representing data embodied in a transmission signal having a center frequency and at least one carrier wave, the transmission frame comprising:

an interleaved sequence of cluster segments, the cluster segments taken from M clusters of data, each cluster of data comprising J cluster segments, where M>

1 and J>

1;

wherein each cluster segment of a respective cluster comprises;

a cluster synchronization field comprising at least c bits taken from a (J)(c) bit cluster synchronization word not larger than (J)(c) bits and wherein the cluster synchronization word is the same for each of the M clusters of data;

a global channel information field comprising a g bits taken from a global channel information word not larger than (J)(g) bits and wherein the global channel information word represents data first block coded and then convolutionally coded; and

a program cluster segment of a program cluster, wherein the program cluster represents at least k program channels, where k>

1, and two fields of cluster control information, which are duplicates of each other, and wherein the cluster control information represents data first block coded and then convolutionally coded, and wherein each of the at least k program channels represents audio-encoded data.

26. A receiver comprising:

circuitry that provides a base-band signal representing a received transmission frame, the received transmission frame comprising

an interleaved sequence of cluster segments, the cluster segments taken from M clusters of data, each cluster of data comprising J cluster segments, where M>

1 and J>

1;

wherein each cluster segment of a respective cluster comprises;

a cluster synchronization field;

a global information field; and

a program cluster segment of a program cluster, wherein the program cluster represents at least k program channels, where k>

1, and cluster control information; and

a demultiplexer for separating out each of the M clusters of data.

27. A receiver comprising:

circuitry that provides a base-band signal representing a received transmission frame, the transmission frame comprising

an interleaved sequence of cluster segments, the cluster segments taken from M clusters of data, each cluster of data comprising J cluster segments, where M>

1 and J>

1;

wherein each cluster segment of a respective cluster comprises;

a cluster synchronization field comprising at least c bits taken from a (J)(c) bit channel synchronization word not larger than (J)(c) bits;

a global channel information field comprising a g bits taken from a global channel information word not larger than (J)(g) bits; and

a program cluster segment of a program cluster, wherein the program cluster represents at least k program channels, where k>

1, and two fields of cluster control information which are duplicates of each other; and

a demultiplexer for separating out each of the M clusters of data.

28. A receiver comprising:

circuitry that provides a base-band signal representing a received transmission frame, the transmission frame comprising

an interleaved sequence of cluster segments, the cluster segments taken from M clusters of data, each cluster of data comprising J cluster segments, where M>

1 and J>

1;

wherein each cluster segment of a respective cluster comprises;

a cluster synchronization field comprising at least c bits taken from a (J)(c) bit cluster synchronization word not larger than (J)(c) bits and wherein the cluster synchronization word is the same for each of the M clusters of data;

a global channel information field comprising a g bits taken from a global channel information word not larger than (J)(g) bits and wherein the global channel information word represents data first block coded and then convolutionally coded; and

a program cluster segment of a program cluster, wherein the program cluster represents at least k program channels, where k>

1, and two fields of cluster control information, which are duplicates of each other, and wherein the cluster control information represents data first block coded and then convolutionally coded, and wherein each of the at least k program channels represents audio encoded data; and

a demultiplexer for separating out each of the M clusters of data.

29. A transmitter comprising:

circuitry that provides a base-band signal representing a transmission frame, the transmission frame comprising

an interleaved sequence of cluster segments, the cluster segments taken from M clusters of data, each cluster of data comprising J cluster segments, where M>

1 and J>

1;

wherein each cluster segment of a respective cluster comprises;

a cluster synchronization field;

a global information field; and

a program cluster segment of a program cluster, wherein the program cluster represents at least k program channels, where k>

1, and cluster control information; and

a modulator for transmitting the transmission frame.

30. A transmitter comprising:

circuitry that provides a base-band signal representing a transmission frame, the transmission frame comprising

an interleaved sequence of cluster segments, the cluster segments taken from M clusters of data, each cluster of data comprising J cluster segments, where M>

1 and J>

1;

wherein each cluster segment of a respective cluster comprises;

a cluster synchronization field comprising at least c bits taken from a (J)(c) bit channel synchronization word not larger than (J)(c) bits;

a global channel information field comprising a g bits taken from a global channel information word not larger than (J)(g) bits; and

a program cluster segment of a program cluster, wherein the program cluster represents at least k program channels, where k>

1, and two fields of cluster control information which are duplicates of each other; and

a modulator for transmitting the transmission frame.

31. A transmitter comprising:

circuitry that provides a base-band signal representing a transmission frame, the transmission frame comprising

an interleaved sequence of cluster segments, the cluster segments taken from M clusters of data, each cluster of data comprising J cluster segments, where M>

1 and J>

1;

wherein each cluster segment of a respective cluster comprises;

a cluster synchronization field comprising at least c bits taken from a (J)(c) bit cluster synchronization word not larger than (J)(c) bits and wherein the cluster synchronization word is the same for each of the M clusters of data;

a global channel information field comprising a g bits taken from a global channel information word not larger than (J)(g) bits and wherein the global channel information word represents data first block coded and then convolutionally coded; and

a program cluster segment of a program cluster, wherein the program cluster represents at least k program channels, where k>

1, and two fields of cluster control information, which are duplicates of each other, and wherein the cluster control information represents data first block coded and then convolutionally coded, and wherein each of the at least k program channels represents audio encoded data; and

a modulator for transmitting the transmission frame.