Communications systems and methods

• US 20050111524A1
• Filed: 07/19/2004
• Published: 05/26/2005
• Est. Priority Date: 07/18/2003
• Status: Active Grant

• Current Assignee: Tahoe Research Limited (f/k/a Learndale Limited) (Vector Capital Corporation)
• Original Assignee: Staccato Communications Incorporated
• Inventors: Baker, David, Moore, Mark Justin
• Granted Patent: US 7,457,350 B2
• Time in Patent Office: Days
• US Class Current: 375/147
• CPC Class Codes: H04B 1/71637 Receiver aspects H04B1/7183 takes precedence
• CPC Class Codes: H04B 1/719 Interference-related aspects

Abstract

This invention generally relates to wired and wireless ultra wideband (UWB) data communications apparatus and methods, and in particular to UWB receiver systems and architectures, and to correlators therefore. An ultra wideband (UWB) receiver system comprising: a receiver front end to receive a UWB signal having a plurality of multipath components; and a correlator coupled to said receiver front end to correlate said UWB signal with a reference signal; and wherein said UWB signal comprises a plurality of pulses; wherein each said pulse has a plurality of multipath components; wherein said reference signal comprises a plurality of multipath components of a said pulse; and wherein said correlator comprises at least one correlator module configured to correlate a plurality of said multipath components of a said pulse with said reference signal.

Claims

1-24. -24. (canceled)

25. An ultra wideband (UWB) receiver system comprising:

a receiver front end to receive a UWB signal having a plurality of multipath components;

wherein said UWB signal comprises a plurality of pulses;

wherein each said pulse has a plurality of multipath components; and

a digital correlator coupled to said receiver front end to digitally correlate each of said plurality of UWB signal pulses with a common digital reference signal waveshape; and

wherein said reference signal waveshape comprises a plurality of multipath components of a said pulse; and

wherein said digital correlator comprises at least one digital correlator module, a said correlator module being configured to correlate a plurality of said multipath components of a said pulse with said reference signal waveshape.

26. A UWB receiver system as claimed in claim 25 further comprising a reference signal memory coupled to said correlator, to store said digital reference signal waveshape.

27. A UWB receiver system as claimed in claim 26 wherein said stored reference signal waveshape comprises a template of a said pulse, said template including at least two substantially time-resolved multipath components of a said pulse.

28. A UWB receiver system as claimed in claim 25 wherein said at least one correlator module has an accumulator to accumulate a correlation value for said plurality of multipath components of said pulse.

29. A UWB receiver system as claimed in claim 25 comprising a plurality of said correlator modules each coupled to said receiver front end and each for correlating a plurality of multipath components of a said pulse with said reference signal waveshape.

30. A UWB receiver system as claimed in claim 29 wherein each said correlator module comprises a plurality of multiply units each configured to receive a differently delayed UWB signal sample from said receiver front end and each configured to receive a correspondingly delayed sample of said reference signal waveshape, said multiply units being coupled to a common accumulator.

31. A UWB receiver system as claimed in claim 29 wherein said correlator modules each receive a differently delayed portion of said reference signal waveshape, and further comprising a selector to select one of more correlation outputs of said correlator modules for further processing.

32. A UWB receiver system as claimed in claim 25 further comprising a memory coupled to said at least one correlator module to store a partial correlation result, and to provide a stored partial correlation result to said correlator module.

33. A UWB receiver system as claimed in claim 32 further comprising a controller to control provision of said reference signal to said correlator to interleave correlation of multipath components of successive ones of said pulses in a common said correlator module.

34. A UWB receiver system as claimed in claim 32 further comprising a multiplexer to time multiplex a said correlator module for correlating pulses having time overlapping multipath components by summing partial correlations of said UWB signal and said digital reference signal waveshape.

35. A UWB receiver system comprising:

a receiver front end to receive a UWB signal;

wherein said UWB signal comprises a plurality of pulses; and

a digital correlator coupled to said receiver front end to digitally correlate each of said plurality of UWB signal pulses with a common digital reference signal waveshape; and

wherein said correlator comprises a plurality of correlation modules to perform a plurality of correlations substantially in parallel between said UWB signal and successively delayed versions of said digital reference signal waveshape to locate a said pulse.

36. A UWB receiver system as claimed in claim 35 wherein said correlator is configured to locate a position in time of a said pulse.

37. A UWB receiver system as claimed in claim 35 wherein said correlator is further configured to determine a phase of a said pulse.

38. A UWB receiver system as claimed in claim 35 wherein said successively delayed versions of said digital reference signal waveshape overlap in time.

39. A UWB reference signal store for use in correlating a received UWB signal with a UWB reference signal, said UWB signal comprising a pulse having a plurality of multipath components, the signal store comprising a memory for storing said UWB reference signal, the memory having a plurality of outputs, each output providing a set of successive samples of a said UWB pulse, successive ones of said outputs being configured to provide successively delayed versions of a said pulse.

40. A UWB reference signal store as claimed in claim 39 configured for use with a digital correlator for digitally correlating each of said plurality of UWB signal pulses with a common digital UWB reference signal waveshape, said reference signal waveshape comprising a plurality of multipath components of a said pulse, wherein said digital correlator comprises at least one digital correlator module, a said correlator module being configured to correlate a plurality of said multipath components of a said pulse with said reference signal waveshape.

41. A UWB reference signal store as claimed in claim 39 configured for use with a digital correlator for digitally correlating each of said plurality of UWB signal pulses with a common digital UWB reference signal waveshape, said reference signal waveshape comprising a plurality of multipath components of a said pulse, wherein said digital correlator comprises at least one digital correlator module, a said correlator module being configured to correlate a plurality of said multipath components of a said pulse with said reference signal waveshape.

42. A UWB reference signal store as claimed in claim 39 wherein said successively delayed versions of a said pulse overlap in time.

43. A UWB reference signal store as claimed in claim 39 further comprising a plurality of inputs for said memory for writing a said set of successive samples of a UWB input signal into said memory.

44. A UWB reference signal store as claimed in claim 39 configured to store said UWB reference signal as a series of pulse-bearing parts of a UWB signal representing multipath components of said signal in combination with one or more multipath delays.

45. A UWB reference signal store as claimed in claim 44 further comprising means to locate a said multipath component of a UWB signal for storing in said memory.

46. A method of demodulating a UWB signal having a plurality of multipath components, the method comprising:

receiving a plurality of said UWB signals;

digitally correlating said plurality of UWB signals including said multipath components with a common digital reference signal waveshape including a plurality of multipath components to provide a digital correlation value including correlation contributions for said multipath components; and

demodulating said UWB signal responsive to said digital correlation value.

47. A method as claimed in claim 46 wherein said correlating comprises correlating said UWB signal with a plurality of delayed versions of said reference signal.

48. A method as claimed in claim 46 wherein said UWB signal comprises a plurality of pulses having interleaved multipath components, the method further comprising interleaving correlating of said multipath components of said UWB and reference signals to determine a correlation value for each of said UWB signal pulses having an interleaved multipath component.

49. A UWB receiver for demodulating a UWB signal having a plurality of multipath components, the receiver comprising:

means for receiving a plurality of said UWB signals;

means for digitally correlating said plurality of UWB signals including said multipath components with a common digital reference signal waveshape including a plurality of multipath components to provide a digital correlation value including correlation contributions for said multipath components; and

demodulating said UWB signal responsive to said digital correlation value.