Frame format and frame assembling/disassembling method for the frame format

• US 20050220110A1
• Filed: 06/01/2005
• Published: 10/06/2005
• Est. Priority Date: 01/18/2000
• Status: Active Grant

• Current Assignee: ViaSat Incorporated
• Original Assignee: ViaSat Incorporated
• Inventors: Agarwal, Anil K.
• Granted Patent: US 7,570,645 B2
• Time in Patent Office: Days
• US Class Current: 370/392
• CPC Class Codes: H04B 7/1851 Systems using a satellite or space-based relay H04B7/18508, H04B7/18521 take precedence; providing specific services H04B7/18523 - H04B7/18576
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/0057 Block codes H04L1/0061, H04L1/0064 take precedence
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/0075 Transmission of coding parameters to receiver H04L1/0023 takes precedence
• CPC Class Codes: H04L 1/0083 Formatting with frames or packets; Protocol or part of protocol for error control
• CPC Class Codes: H04L 12/5601 Transfer mode dependent, e.g. ATM
• CPC Class Codes: H04L 2012/5607 Radio
• CPC Class Codes: H04L 2012/5662 Macrocells or frames
• CPC Class Codes: H04L 2012/5665 Interaction of ATM with other protocols
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• 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

Abstract

A method of assembling a plurality of frames including cell/packet-formatted data according to a predetermined frame format for transmission in a communication signal in a wireless or satellite environment. The method begins by assembling a data payload for each frame having a first variable size, including at least one of a partial data cell/packet and a complete data cell/packet. Then, for each frame a block code having a second variable size is generated for use in error correction. Each frame is provided with a frame header which defines aspects of said frame. Finally, the data payload, the block code and the format header are combined to form a frame corresponding to the plurality of frames, the format header defining a first portion of the frame, the data payload defining a second portion of the frame and the block code defining a third portion of the frame.

Claims

1. An arrangement of signals in a frame format for a communication signal containing a bit stream including cell- or -packet-formatted data, said bit stream being organized into a plurality of frames according to said frame format which comprises:

a frame header;

a data payload having a first variable size; and

a block code having a second variable size which is used for error correction;

wherein said data payload includes at least one of a partial data cell or packet and/or at least one of a complete data cell or packet.

2. The arrangement of signals in a frame format defined in claim 1, wherein said data payload comprises at least one partial ATM data cell.

3. The arrangement of signals in a frame defined in claim 1, wherein said data payload comprises at least one complete ATM data cell.

4. The arrangement of signals in a frame format defined in claim 1, wherein said data payload further comprises at least one of a partial packet of compressed data and a complete packet of compressed data.

5. The arrangement of signals in a frame format defined in claim 4, wherein said at least one of a partial packet of compressed data and a complete packet of compressed data includes at least one partial ATM data cell.

6. The arrangement of signals in a flame format defined in claim 4, wherein said at least one of a partial packet of compressed data and a complete packet of compressed data includes at least one complete ATM data cell.

7. The arrangement of signals in a frame format defined in claim 4, wherein said data payload comprises a complete ATM data cell, a partial ATM data cell and a complete packet of compressed data.

8. The arrangement of signals in a frame format defined in claim 1, wherein said frame header comprises:

a first header field which defines a number of data cells or packets in said data payload, said number of data cells or packets including only complete data cells or packets and any partial data cell or packet which follows said complete data cells or packets;

a second header field which defines a size of a first partial data cell or packet that precedes any complete data cells or packets included in said data payload; and

a third header field which defines a frame number of a corresponding one of said plurality of frames.

9. The arrangement of signals in a frame format defined in claim 8, wherein said frame header further comprises a fourth header field which defines a predetermined characteristic of said block code in accordance with said frame number of the corresponding one of said plurality of frames.

10. The arrangement of signals in a frame format defined in claim 9, wherein said predetermined characteristic corresponds to the second variable size of said block code.

11. The arrangement of signals in a frame format defined in claim 10, wherein said predetermined characteristic corresponds to the second variable size of said block code of a current frame of said plurality of frames.

12. The arrangement of signals in a frame format defined in claim 10, wherein said predetermined characteristic corresponds to the second variable size of said block code of a subsequent frame of said plurality of frames.

13. The arrangement of signals in a frame format defined in claim 10, wherein

said second variable size of said block code depends on a bit error rate of said communication signal.

14. The arrangement of signals in a frame format defined in claim 8, wherein said data cells or packets are ATM formatted.

15. The arrangement of signals in a frame format defined in claim 1, wherein a size of said block code is visible and depends on a bit error rate of said communication signal.

16. The arrangement of signals in a frame format defined in claim 8, wherein said data cells or packets are frame relay formatted.

17. The arrangement of signals in a frame format defined in claim 1, wherein said cells or packets are one of ATM-, Internet- or frame relay-formatted.

18. The arrangement of signals in a frame format defined in claim 1, wherein said data payload further comprises a pattern for identifying the boundary of a corresponding frame in order to facilitate frame synchronization.

19. A frame format for a communication signal containing a bit stream including asynchronous transfer mode (ATM) formatted data, said bit stream being organized into a plurality of frames according to said frame format which comprises:

a frame header,

a data payload having a first variable size; and

a block code having a second variable size which is used for error correction;

wherein said data payload includes at least one of a partial ATM cell and a complete ATM cell.

20. The frame format defined in claim 19, wherein said second variable size of said block code depends on a bit error rate of said communication signal.

21. The frame format defined in claim 20, wherein said block code comprises Reed-Solomon Coding.

22. A frame format for a communication signal containing a bit stream including asynchronous transfer mode (ATM) formatted data, said bit stream being organized into a plurality of frames according to said frame format which comprises:

a frame header;

a data payload having a first variable size; and

a block code having a second variable size which is used for error correction;

wherein said data payload comprises a synchronization pattern which corresponds to sequential numbers which are each stored in corresponding byte position of said data payload.

23. A communication system for efficiently transmitting information signals in discrete cell/packets, said system comprising at least two local area networks that are connected by a satellite/wireless communication link, each local area network comprising:

(a) a switch for providing a plurality of cell/packets, each cell/packet comprising a header and a payload;

(b) a cell/packet processing apparatus connected between said switch and said satellite/wireless communication link, said apparatus comprising;

(i) means for discriminating each cell/packet in said plurality of cell/packets;

(ii) means for assembling said cell/packets as a data payload for an individual frame having a first variable size;

(iii) means for generating a header for each frame;

(iv) means for generating a block code having a second is variable for each frame; and

(v) frame assembler means for combining said header, said block code and said payload to form a frame; and

(c) means for transmitting said assembled frame onto said satellite/wireless link.

24. A communication system as set forth in claim 23 further comprising encoding means for encoding said assembled frame.

25. A communication system as set forth in claim 23 further comprising an interleaver for interleaving a plurality of said assembled frames.

26. A communication system as set forth in claim 23 further comprising:

means for receiving said transmitted frames from said satellite/wireless communication link; and

a frame disassembler for disassembling said frames into a plurality of cell/packets.

27. A communication system as set forth in claim 26, wherein said apparatus further comprises:

(i) correcting detected errors; and

(ii) means for extracting data from said received cell/packets in accordance with information in said header.

28. A communication system as set forth in claim 27, further comprising means for deinterleaving a group of interleaved frames.

29. A communication system as set forth in claim 27, wherein said cell/packets comprise ATM cells.

30. A communication system as set forth in claim 27, wherein said cell/packets comprise frame relay packets.

31. A communication system as set forth in claim 27, wherein said cell/packets comprise Internet packets.