Method of processing an incident pulsed UWB signal received by an independent data device of a wireless data communication system of the WPAN type, and corresponding independent data device

• US 7,542,486 B2
• Filed: 03/03/2004
• Issued: 06/02/2009
• Est. Priority Date: 03/03/2003
• Status: Active Grant

• Current Assignee: STMicroelectronics International N.V. (STMicroelectronics NV)
• Original Assignee: STMicroelectronics NV
• Inventors: Cattaneo, Chiara
• Primary Examiner(s): NGUYEN, HANH N
• Application Number:
  US10/792,032
• Publication Number:
  US 20040218581A1
• Time in Patent Office: 1,917 Days
• Field of Search: 370/503, 370/328, 370/329, 370/338, 370/350, 370/509, 370/510, 370/512, 370/321, 370/347, 370/468, 370/442, 370/471, 370/473, 455/574, 455/343.5, 455/444, 455/426.1, 455/426.2, 375/354, 375/340, 375/316, 375/343
• US Class Current: 370/510
• CPC Class Codes: H04B 1/7183 Synchronisation
• CPC Class Codes: H04L 25/0226 sounding signals per se

Abstract

A method for processing an incident pulsed signal of an ultra wide band type received over a channel by a data device operating in a wireless data communications system is provided. The incident pulsed signal carries information within a super-frame structure. Upon reception of each super-frame structure by a data device, coarse synchronization is performed with another data device acting as a coordinator device for the wireless data communications system. The coarse synchronization uses a first training sequence. Upon reception of each frame allocated to the data device operating within the super-frame structure, channel estimation is performed using a second training sequence. The channel estimation also performs a frame synchronization.

Claims

1. A method for processing an incident pulsed signal of an ultra wide band type received over a channel by a data device operating in a wireless data communications system, the incident pulsed signal carrying information within a super-frame structure, each super-frame structure comprising a plurality of frames respectively allocated for communications between specific pairs of data devices operating in the wireless data communications system and a header including at least one first training sequence, each frame comprising a preamble including at least one second training sequence, the method comprising:

upon reception of each super-frame structure by a data device, performing coarse synchronization with another data device acting as a coordinator device for the wireless data communications system, the coarse synchronization using the first training sequence; and

upon reception of each frame allocated to the data device operating within the super-frame structure, performing channel estimation using the second training sequence, the channel estimation being based on at least one signal slice having ends temporally defined with respect to a result of the coarse synchronization, the channel estimation also performing a frame synchronization.

2. A method according to claim 1, wherein the channel has a predetermined maximum length;

wherein the header further includes a time of arrival indication for each frame;

wherein the coarse synchronization delivers a first delay information corresponding to a delay associated with the received incident pulsed signal; and

wherein the channel estimation begins on a signal slice starting at an instant equal to the time of arrival of the frame increased by a difference between the first delay information and a predetermined offset, the signal slice having a size equal to a maximum channel length increased by the predetermined offset.

3. A method according to claim 2, wherein the channel comprises a multipath channel;

and wherein the predetermined offset comprises a first offset taking into account that the first delay information is associated with a different path of the channel.

4. A method according to claim 3, wherein the first offset is equal to about 10 ns.

5. A method according to claim 3, wherein the predetermined offset comprises a second offset taking into account differences between propagation delays between the coordinator device and a data device, and between a pair of data devices.

6. A method according to claim 5, wherein the second offset depends on a maximum distance between two data devices.

7. A method according to claim 5, wherein the second offset is equal to about 30 ns.

8. A method according to claim 5, wherein the predetermined offset is a sum of the first and second offsets.

9. A method according to claim 1, wherein the first training sequence is identical to the second training sequence.

10. A method according to claims 1, wherein at least one of performing the coarse synchronization and the channel estimation comprises performing a digital correlation.

11. A method according to claim 10, wherein the second training sequence is a dedicated pulse train having a pulse repetition period;

and wherein the digital correlation performed during the channel estimation comprises coherent integration of successive signal slices having a same size and being mutually temporally shifted with the pulse repetition period.

12. A method according to claim 1, wherein the wireless data communication system comprises a wireless personal area network of the piconet type.

13. A data device of a wireless data communications system comprising:

a receiver for receiving an incident pulsed signal of an ultra wide band type over a channel, the incident pulsed signal carrying information within a super-frame structure, each super-frame structure comprising a plurality of frames respectively allocated to communications between specific pairs of data devices operating in the wireless data communications system and a header including at least one first training sequence, each frame comprising a preamble including at least one second training sequence; and

a processor connected to said receiver and comprising

a coarse synchronizer for performing, upon reception of each super-frame structure, a coarse synchronization with another data device acting as a coordinator device of the wireless data communications system, said coarse synchronizer using the first training sequence, and

a channel estimator for performing, upon reception of each frame allocated to the data device within the super-frame structure, channel estimation using the second training sequence, the channel estimation being based on at least one signal slice having ends temporally defined with respect to a result of the coarse synchronization, said channel estimator also performing a frame synchronization.

14. A data device according to claim 13, wherein the channel has a predetermined maximum length;

wherein the header further includes a time of arrival indication for each frame;

wherein said coarse synchronizer delivers a first delay information corresponding to a delay associated with the received incident pulsed signal; and

wherein said channel estimator begins the channel estimation on a signal slice starting at an instant equal to the time of arrival of the frame increased by a difference between the first delay information and a predetermined offset, the signal slice having a size equal to a maximum channel length increased by the predetermined offset.

15. A data device according to claim 14, wherein the channel comprises a multipath channel;

and wherein the predetermined offset comprises a first offset taking into account that the first delay information is associated with a different path of the channel.

16. A data device according to claim 15, wherein the first offset is equal to about 10 ns.

17. A data device according to claim 15, wherein the predetermined offset comprises a second offset taking into account differences between propagation delays between the coordinator device and a data device, and between a pair of data devices.

18. A data device according to claim 17, wherein said second offset depends on a maximum distance between two data devices.

19. A data device according to claim 17, wherein the second offset is equal to about 30 ns.

20. A data device according to claim 17, wherein the predetermined offset is a sum of the first and second offsets.

21. A data device according to claim 13, wherein the first training sequence is identical to the second training sequence.

22. A data device according to claim 13, wherein at least one of said coarse synchronizer and said channel estimator comprise a digital correlator.

23. A data device according to claim 22, wherein the second training sequence is a dedicated pulse train having a pulse repetition period;

and wherein said digital correlator comprises a coherent integrator for performing during the channel estimation a coherent integration of successive signal slices having a same size and being mutually temporally shifted with the pulse repetition period.

24. A data device according to claim 13, wherein the wireless data communication system comprises a wireless personal area network of the piconet type.

25. A wireless data communications system comprising:

a plurality of data devices, each data device comprising

a receiver for receiving an incident pulsed signal of an ultra wide band type over a channel, the incident pulsed signal carrying information within a super-frame structure, each super-frame structure comprising a plurality of frames respectively allocated to communications between specific pairs of data devices operating in the wireless data communications system and a header including at least one first training sequence, each frame comprising a preamble including at least one second training sequence, and

a processor connected to said receiver and comprising

a coarse synchronizer for performing, upon reception of each super-frame structure, a coarse synchronization with another data device acting as a coordinator device of the wireless data communications system, said coarse synchronizer using the first training sequence, and

a channel estimator for performing, upon reception of each frame allocated to the data device within the super-frame structure, channel estimation using the second training sequence, the channel estimation being based on at least one signal slice having ends temporally defined with respect to a result of the coarse synchronization, said channel estimator also performing a frame synchronization.

26. A wireless data communications system according to claim 25, wherein the channel has a predetermined maximum length;

wherein the header further includes a time of arrival indication for each frame;

wherein said coarse synchronizer delivers a first delay information corresponding to a delay associated with the received incident pulsed signal; and

wherein said channel estimator begins the channel estimation on a signal slice starting at an instant equal to the time of arrival of the frame increased by a difference between the first delay information and a predetermined offset, the signal slice having a size equal to a maximum channel length increased by the predetermined offset.

27. A wireless data communications system according to claim 26, wherein the channel comprises a multipath channel;

and wherein the predetermined offset comprises a first offset taking into account that the first delay information is associated with a different path of the channel.

28. A wireless data communications system according to claim 27, wherein the first offset is equal to about 10 ns.

29. A wireless data communications system according to claim 27, wherein the predetermined offset comprises a second offset taking into account differences between propagation delays between the coordinator device and a data device, and between a pair of data devices.

30. A wireless data communications system according to claim 29, wherein said second offset depends on the maximum distance between two data devices.

31. A wireless data communications system according to claim 29, wherein the second offset is equal to about 30 ns.

32. A wireless data communications system according to claim 29, wherein the predetermined offset is a sum of the first and second offsets.

33. A wireless data communications system according to claim 25, wherein the first training sequence is identical to the second training sequence.

34. A wireless data communications system according to claim 25, wherein at least one of said coarse synchronizer and said channel estimator comprises a digital correlator.

35. A wireless data communications system according to claim 34, wherein the second training sequence is a dedicated pulse train having a pulse repetition period;

and wherein said digital correlator comprises a coherent integrator for performing during the channel estimation a coherent integration of successive signal slices having a same size and being mutually temporally shifted with the pulse repetition period.

36. A wireless data communications system according to claim 25, wherein the wireless data communication system comprises a wireless personal area network of the piconet type.