System and method for multiplexing PDH and packet data

• US 20060153244A1
• Filed: 01/11/2005
• Published: 07/13/2006
• Est. Priority Date: 01/11/2005
• Status: Active Grant

• Current Assignee: Harris Stratex Networks, Inc.
• Original Assignee: Harris Corporation (L3Harris Technologies, Inc.)
• Inventors: Jao, Tjo San
• Granted Patent: US 7,782,812 B2
• Time in Patent Office: Days
• US Class Current: 370/503
• CPC Class Codes: H04J 3/0685 Clock or time synchronisation in a node; Intranode synchronisation
• CPC Class Codes: H04J 3/073 Bit stuffing, e.g. PDH
• CPC Class Codes: H04J 3/1623 Plesiochronous digital hierarchy [PDH]
• CPC Class Codes: H04J 3/247 ATM or packet multiplexing

Abstract

A method of efficiently combining data from at least a plurality of a first type of data source and a second type of data source. The method comprises synchronizing the plural first type of data sources to thereby generate a synchronized data rate, providing a frame having plural bit positions, assigning the synchronized first type of data in ones of the bit positions of the frame, and arranging the second type of data in the frame as a function of the synchronized data rate.

Claims

1. A method of transmitting data in a communication system adapted to receive a first type of data having two data streams with different clocks and a second type of data comprising the steps of:

(a) receiving data from the first and second types of sources;

(b) providing a frame having plural bit positions;

(c) synchronizing the received first type of data thereby generating a synchronized data rate;

(d) assigning the synchronized first type of data in ones of the bit positions of the frame;

(e) distributing the second type of data in ones of the unassigned bit positions as a function of the synchronized data rate; and

(f) transmitting the frame.

2. The method of claim 1 wherein the step of providing a frame includes providing a frame having plural sub-frames with plural blocks and sub-blocks, each sub-block including a synchronized first type of data bit position or a second type of data bit position and each block having at least one overhead bit position and further including the steps of:

inserting a frame alignment word in bit positions of the first block of the first sub-frame; and

distributing synchronized data bits of the first type of data or data bits of the second type of data in unused overhead bit positions of other blocks.

3. The method of claim 2 wherein the number of sub-frames correlates to the number of received first type of sources.

4. The method of claim 2 further comprising the step of distributing stuffing indication bits in unused overhead bit positions.

5. The method of claim 2 further comprising the step of distributing parity bits in unused overhead bit positions.

6. The method of claim 1 further comprising the step of:

filling in unassigned synchronized first type of data bit positions with data bits of the second type of data.

7. The method of claim 1 wherein the first type of source includes at least one of synchronous, asynchronous, and plesiochronous sources.

8. The method of claim 1 wherein the second type of source includes a packet source.

9. The method of claim 1 wherein the synchronized first type of data and second type of data is assigned by sequential bit interleaving.

10. The method of claim 1 wherein the received first type of sources are synchronized by bit stuffing.

11. A method for transmitting communication signals in a predetermined frame format comprising the steps of:

(a) receiving data from a plurality of sources including a first and second type of data source;

(b) synchronizing the received first type of data source to thereby generate a synchronized data rate; and

(c) transmitting the synchronized first type of data and received second type of data in a predetermined frame format whereby the packet data is assigned in the predetermined frame format as a function of the synchronized data rate.

12. The method of claim 11 wherein the first type of data source includes at least one of synchronous, asynchronous, and plesiochronous sources.

13. The method of claim 11 wherein the second type of data source is a packet data source.

14. The method of claim 11 further comprising the step of sequentially bit interleaving synchronized first type of data and second type of data in the frame format.

15. In a method where data from plural plesiochronous digital hierarchy (PDH) sources and from a packet source are received, assigned to bit positions in a frame, and transmitted as a single data stream the improvement wherein the data received from the packet source is arranged in the data stream as a function of a synchronized data rate of the received PDH sources.

16. A method of combining data from plural first type of data sources and at least one second type of data source comprising the steps of:

(a) synchronizing the plural first type of data sources to thereby generate a synchronized data rate;

(b) providing a frame having plural bit positions;

(c) assigning the synchronized first type of data in ones of the bit positions of the frame; and

(d) arranging the second type of data in the frame as a function of the synchronized data rate to thereby combine data from different types of data sources.

17. The method of claim 16 further comprising the step of.

filling in unassigned synchronized first type of data bit positions with data bits from the second type of data source.

18. The method of claim 16 wherein the step of providing a frame includes providing a frame having plural sub-frames with plural blocks and sub-blocks, each sub-block including a synchronized first type of data bit position or a second type of data bit position and each block having at least one overhead bit position and further including the steps of:

inserting a frame alignment word in bit positions of the first block of the first sub-frame; and

distributing synchronized data bits of the first type of data or data bits of the second type of data in unused overhead bit positions of other blocks.

19. The method of claim 18 wherein the number of sub-frames correlates to the number of received first type of sources.

20. The method of claim 18 further comprising the step of distributing stuffing indication bits in unused overhead bit positions.

21. The method of claim 18 further comprising the step of distributing parity bits in unused overhead bit positions.

22. The method of claim 16 wherein the first type of data source includes at least one of synchronous, asynchronous, and plesiochronous sources.

23. The method of claim 16 wherein the second type of data source includes a packet source.

24. The method of claim 16 wherein the synchronized first type of data and second type of data is assigned by sequential bit interleaving.

25. The method of claim 16 wherein the first type of data sources are synchronized by bit stuffing.

26. A method of transmitting data received from plural sources that are not synchronized with each other and a packet source as a single data stream comprising the steps of:

synchronizing data received from the plural sources that are not synchronized with each other to thereby generate a synchronized data rate;

providing a frame format comprising a plurality of frames each frame having plural sub-frames the number of which correlates to the number of received plural sources that are not synchronized with each other and each sub-frame comprising a plurality of blocks each block comprising;

at least one overhead bit position,

(n) bit positions of the synchronized data,

(m) bit positions of data received from the packet source arranged as a function of the synchronized data rate, and

a plurality of sub-blocks each having a bit position for the synchronized data or a bit position for data received from the packet source;

assigning the synchronized data and data received from the packet source in bit positions of the frame format; and

transmitting the assigned data as a single data stream.

27. The method of claim 26 further comprising the step of filling unassigned bit positions with packet data.

28. The method of claim 26 further comprising the steps of:

inserting a frame alignment word in bit positions of the first block of the first sub-frame; and

distributing synchronized data bits or data bits received from the packet source in unassigned overhead bit positions of other blocks.

29. The method of claim 26 wherein the plural sources that are not synchronized with each other includes at least one of synchronous, asynchronous, and plesiochronous sources.

30. The method of claim 26 further comprising the step of sequentially bit interleaving the synchronized data bits and data bits received from the packet source in the frame format.

31. The method of claim 26 wherein the data received from the plural sources that are not synchronized with each other are synchronized by bit stuffing.

32. The method of claim 26 further comprising the step of distributing stuffing indication bits in unassigned overhead bit positions.

33. The method of claim 26 further comprising the step of distributing parity bits in unassigned overhead bit positions.

34. In a system where data from sources having different synchronisms and packet sources is transmitted in a frame format as a single data stream the improvement wherein the packet data is arranged in said data stream as a function of a data rate of said sources having different synchronisms.

35. The system of claim 34 wherein said sources having different synchronisms includes at least one of synchronous, asynchronous, and plesiochronous sources.

36. The system of claim 34 further comprising an interleaver wherein said data from sources having different synchronisms and packet sources are sequentially bit interleaved in said single data stream.

37. A system adaptable to receive data from plural first type of data sources and at least one second type of data source that are not synchronized with each other and to transmit the data as a single data stream,

wherein if data from both the plural first type of data source and second type of data source are received,

the plural first type of data source is synchronized to thereby generate a synchronized data rate, a frame is provided having plural bit positions, the synchronized first type of data are assigned in ones of the bit positions of the frame format, and the second type of data are arranged in the frame format as a function of the synchronized data rate for transmission thereof,

wherein if data from only the first type of data source is received,

the plural first type of data source is synchronized to thereby generate a synchronized data rate, a frame format is provided having plural bit positions, and the synchronized first type of data are assigned in ones of the bit positions of the frame format for transmission thereof,

wherein if data from only the second type of data source is received,

a frame format is provided having plural bit positions and the second type of data are arranged in the frame format for transmission thereof.

38. The system of claim 37 wherein said plural first type of data sources first type of data source includes at least one of synchronous, asynchronous, and plesiochronous sources.

39. The system of claim 37 wherein the second type of data source is a packet data source.

40. The system of claim 37 wherein said frame format comprises a plurality of frames each frame having plural sub-frames the number of which correlates to the number of received plural sources that are not synchronized with each other and each sub-frame comprising a plurality of blocks each block comprising:

at least one overhead bit position,

(n) bit positions of synchronized data from the plural sources;

(m) bit positions of data received from the packet source arranged as a function of the synchronized data rate, and

a plurality of sub-blocks each having a bit position for the synchronized data or a bit position for data received from the packet source.

41. The system of claim 37 wherein the synchronized first type of data bits and the second type of data bits are sequentially bit interleaved in the frame format.