Mode controller for signal acquisition and tracking in an ultra wideband communication system

• US 20030067963A1
• Filed: 08/08/2002
• Published: 04/10/2003
• Est. Priority Date: 12/11/1998
• Status: Active Grant

• Current Assignee: North Star Innovations Inc. (Wi-LAN Inc.)
• Original Assignee: Freescale Semiconductor, Inc. (NXP Semiconductors NV)
• Inventors: Miller, Timothy R., Joseph, Deepak M., Lynch, Gerard P.
• Granted Patent: US 7,110,473 B2
• Time in Patent Office: Days
• US Class Current: 375/130
• CPC Class Codes: H04B 1/71632 Signal aspects H04B1/7172 and H04B1/7176 take precedence
• CPC Class Codes: H04B 1/7183 Synchronisation
• CPC Class Codes: H04L 25/061 providing hard decisions only; arrangements for tracking or suppressing unwanted low frequency components, e.g. removal of dc offset removal of dc offset in coupling arrangements H04L25/029, H04L25/0296
• CPC Class Codes: H04L 25/4902 Pulse width modulation; Pulse position modulation
• CPC Class Codes: H04L 27/0004 using wavelets

Abstract

A system and method is provided for controlling the mode of operation in a UWB receiver. In one variation, the system and method determines the mode of operation by reading a set number of samples of the signal, estimating mode parameters, calculating a mode probability, and then transitioning in a finite state machine between a track and an acquisition state depending on the value of the mode probability. Exemplary versions of the mode controller include a signal to noise ratio calculator, a signal and noise power estimator, and an AGC initialization circuit.

Claims

1. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, comprising:

a data dependence removal element for receiving the incoming data signal and outputting a data-independent signal that indicates a strength of the incoming data signal independent of data contained in the incoming data signal;

a signal path comprising

a first processor for manipulating the data-independent signal to determine a first intermediate signal; and

a first non-linear function element for performing a non-linear function on the first intermediate signal To determine a signal parameter;

a noise-related path, comprising

a second non-linear function element for performing a non-linear function on the data-independent signal to determine a second intermediate signal;

a second processor for manipulating the second intermediate signal to determine a noise-related parameter; and

a third processor for processing the signal parameter and the noise-related parameter to determine a mode-controlling parameter indicative of the relative signal strength of the incoming data signal.

2. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 1, further comprising a first sub-sampler between the first processor and the first non-linear function element for sampling the first intermediate signal at a first rate and outputting a sampled first intermediate signal to the first non-linear function element.

3. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 1, further comprising a second sub-sampler between the second processor and the comparator for sampling the signal parameter at a second rate and outputting a sampled signal parameter to the comparator.

4. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 1, further comprising an input scaler for multiplying the incoming signal by a first scaling factor before it is input to the data dependence removal element.

5. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 4, wherein the first scaling factor is a factor of 2.

6. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 4, wherein the first scaling factor is programmable.

7. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 1, further comprising a signal path scaler for multiplying the signal parameter by a second scaling factor before it is input to the comparator.

8. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 7, wherein the second scaling factor is a factor of 2.

9. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 7, wherein the second scaling factor is programmable.

10. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 1, further comprising a noise-related path scaler for multiplying the noise-related signal by a third scaling factor before it is input to the comparator.

11. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 10, wherein the third scaling factor is a factor of 2.

12. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 10, wherein the third scaling factor is programmable.

13. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 1, wherein the first processor is a first filter.

14. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 13, wherein the first filter is a finite impulse response filter.

15. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 14, wherein the first filter is a moving average filter.

16. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 13, wherein the first filter is an infinite impulse response filter.

17. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 16, wherein the first filter is a leaky integrator filter.

18. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 1, wherein the second processor is a second filter.

19. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 18, wherein the second filter is a finite impulse response filter.

20. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 19, wherein the second filter is a moving average filter.

21. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 18, wherein the second filter is an infinite impulse response filter.

22. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 21, wherein the second filter is a leaky integrator filter.

23. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 1, wherein the data dependence removal element is an absolute value element that outputs the absolute value of the incoming signal as the data-independent signal.

24. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 1, wherein the first non-linear function element is a first squarer that outputs the square of the first intermediate signal as the signal parameter.

25. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 1, wherein the second non-linear function element is a second squarer that outputs the square of the data-independent signal as the second intermediate signal.

26. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 1, wherein the first processor is an infinite impulse response filter and the second processor is a leaky integrator filter.

27. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 26, wherein the infinite impulse response filter is shaped to approximate an expected correlation signal.

28. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 1, wherein the first processor is a first moving average filter and the second processor is a second moving average filter.

29. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, comprising:

an absolute value element for receiving the incoming data signal and determining an absolute value of the incoming data signal;

a signal path comprising

a first filter for filtering the absolute value of the data signal to determine a first intermediate signal; and

a first squarer for squaring the first intermediate signal to determine a noise-related parameter;

a noise-related path, comprising

a second squarer for squaring the absolute value of the incoming data signal to determine a second intermediate signal; and

a second filter for filtering the second intermediate signal to determine a signal parameter; and

a comparator for comparing the signal parameter and the noise-related parameter to determine a mode-controlling parameter indicative of the relative signal strength of the incoming data signal.

30. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 29, further comprising a first sub-sampler between the first filter and the first squarer for sampling the first intermediate signal at a first rate and outputting a sampled first intermediate signal to the first squarer.

31. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 29, further comprising a second sub-sampler between the second filter and the comparator for sampling the signal parameter at a second rate and outputting a sampled signal parameter to the comparator.

32. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 29, further comprising an input scaler for multiplying the incoming signal by a first scaling factor before it is input to the absolute value element.

33. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 32, wherein the first scaling factor is a factor of 2.

34. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 32, wherein the first scaling factor is programmable.

35. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 29, further comprising a signal path scaler for multiplying the signal parameter by a second scaling factor before it is input to the comparator.

36. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 35, wherein the second scaling factor is a factor of 2.

37. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 35, wherein the second scaling factor is programmable.

38. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 29, further comprising a noise-related path scaler for multiplying the noise-related signal by a third scaling factor before it is input to the comparator.

39. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 38, wherein the third scaling factor is a factor of 2.

40. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 38, wherein the third scaling factor is programmable.

41. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 29, wherein the first filter is a finite impulse response filter.

42. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 41, wherein the first filter is a moving average filter.

43. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 29, wherein the first filter is an infinite impulse response filter.

44. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 43, wherein the first filter is a leaky integrator filter.

45. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 29, wherein the second filter is a finite impulse response filter.

46. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 45, wherein the second filter is a moving average filter.

47. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 29, wherein the second filter is an infinite impulse response filter.

48. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 47, wherein the second filter is a leaky integrator filter.

49. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 29, wherein the first filter is an infinite impulse response filter and the second filter is a leaky integrator filter.

50. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 49, wherein the infinite impulse response filter is shaped to approximate an expected correlation signal.

51. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal, as recited in claim 29, wherein the first filter is a first moving average filter and the second filter is a second moving average filter.

52. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal in an ultrawide bandwidth receiver, comprising:

a signal path for determining a signal parameter of the incoming data signal;

a noise-based path for determining a noise-based parameter of the incoming data signal;

a processor for processing the signal parameter and the noise-related parameter to determine a mode-controlling parameter; and

a controller for transitioning between an acquisition mode and a tracking mode based on the mode-controlling parameter.

53. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal in an ultrawide bandwidth receiver, as recited in claim 52, wherein the signal parameter is an estimate of signal strength and the noise-based parameter is an estimate of signal-plus-noise strength.

54. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal in an ultrawide bandwidth receiver, as recited in claim 52, wherein the processor is a comparator.

55. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal in an ultrawide bandwidth receiver, as recited in claim 52, further comprising

a signal path scaler for scaling the signal parameter to generate a scaled signal parameter,

wherein the processor receives the scaled signal parameter rather than the signal parameter.

56. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal in an ultrawide bandwidth receiver, as recited in claim 52, further comprising

a noise path scaler for scaling the noise-based parameter to generate a scaled noise-based parameter,

wherein the processor receives the scaled noise-based parameter rather than the noise-based parameter.

57. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal in an ultrawide bandwidth receiver, as recited in claim 52, wherein the signal path comprises a filter.

58. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal in an ultrawide bandwidth receiver, as recited in claim 52, wherein the noise path comprises a filter.

59. A mode controller for determining a desired operation mode for acquisition or tracking of an incoming data signal in an ultrawide bandwidth receiver, as recited in claim 52, further comprising an absolute value block for determining an absolute value of the incoming data signal and providing the absolute value of the data signal to the signal path and the noise-based path.