Forward link TDMA power control system and method

• US 6,072,788 A
• Filed: 04/07/1997
• Issued: 06/06/2000
• Est. Priority Date: 04/07/1997
• Status: Expired due to Term

• Current Assignee: Hanger Solutions, LLC (IP Investments Group LLC)
• Original Assignee: Metawave Communications Corp.
• Inventors: Virtue, Mark, Peterson, Curt
• Primary Examiner(s): Kizou, Hassan
• Assistant Examiner(s): Pezzlo, John
• Application Number:
  US08/826,721
• Time in Patent Office: 1,156 Days
• Field of Search: 370/330, 370/337, 370/347, 370/334, 455/562, 455/561, 455/522, 455/69, 455/126, 342/354, 342/457, 342/373
• US Class Current: 370/337
• CPC Class Codes: H04B 7/086 using weights depending on external parameters, e.g. direction of arrival [DOA], predetermined weights or beamforming
• CPC Class Codes: H04W 52/42 in systems with time, space, frequency or polarisation diversity
• CPC Class Codes: H04W 52/52 using AGC [Automatic Gain Control] circuits or amplifiers

Abstract

A system and method are disclosed for independently adjusting the forward channel power level of each time division burst period of a frame of a time divided signal. The disclosed invention teaches the splitting of the time divided signal for provision to independently controllable circuits associated with each burst period of the frame. Each independently controllable circuit includes a controllable attenuator/amplifier and switching device. The attenuator/amplifier is operated to adjust the power level of its associated burst period to a predetermined magnitude. Thereafter, the switching device operates to direct each power adjusted burst period to be transmitted within a predetermined beam of a multi-beam antenna array.

Claims

1. A system for providing a signal within each time division of a predefined frame of signal time divisions of a same frequency with independent power level adjustment, said system comprising:

means operable for each said time division for adjusting the power level of an input signal associated with each said time division to a predetermined magnitude maintained during said associated time division; and

means for selectively switching between each of said power level adjusted signals operable to provide said frame of signal time divisions of said same frequency including said input signal within each said associated time division having said predetermined magnitude.

2. The system of claim 1, wherein said adjusting means comprises:

an independently adjustable attenuator/amplifier for each said input signal associated with each said time division.

3. The system of claim 2, wherein each said attenuator/amplifier is adjusted during a time division other than said associated time division to provide substantially steady state attenuation/amplification of a signal during said associated time division.

4. The system of claim 1, wherein said switching means comprises:

an independently switchable switching device for each signal time division.

5. The system of claim 4, wherein at least one of said switching devices comprises a multiplexer.

6. The system of claim 1, further comprising an antenna array adapted to provide a plurality of radiation beams, said antenna array including circuitry adapted to provide directional communication through ones of said plurality of radiation beams.

7. The system of claim 6, wherein said switching means operates to provide a particular time division of said time division signal to a portion of said circuitry associated with a predetermined beam of said plurality of radiation beams.

8. The system of claim 7, wherein said circuitry comprises a plurality of signal combiner means for combining a plurality of input signal paths into at least one output signal path, wherein at least one signal combiner means of said plurality of signal combiner means is associated with a particular radiation beam of said plurality of radiation beams.

9. The system of claim 6, wherein said antenna array comprises an antenna unit for each radiation beam of said plurality of radiation beams.

10. The system of claim 1, further comprising:

signal splitting means operable to split an input time division signal into a predetermined number of discrete substantially identical time division signals, wherein said splitting means provides said input signals associated with each said time division.

11. The system of claim 10, wherein said predetermined number of discrete time division signals is equal to a number of time divisions associated with said predefined frame of signal time divisions.

12. The system of claim 1, wherein both said power level adjusting means and said switching means are operable under control of a control circuit substantially synchronous with said time divisions.

13. The system of claim 12, wherein said control circuit is operable to control a plurality of associated sets of said power level adjusting means and said switching means, said sets providing independent power level adjustment of a plurality of frames of signal time divisions.

14. A system having a time division input where discrete signals can occur during ones of said time divisions, wherein a predetermined number of time divisions defines a frame, said system comprising:

means for splitting said input signal into a number of different substantially identical signals, wherein said number of signals is at least as great as the number of time divisions in said frame;

means for adjusting the power level of each said split signal to result in a desired amplitude during a particular one of said time divisions; and

means for selectively outputting the power level adjusted split signals to result in substantially only said particular time divisions having said desired amplitude being output.

15. The system of claim 14, wherein said selective outputting means comprises:

a switching medium which samples the output of each adjusting means during said particular time division associated with said adjusting means.

16. The system of claim 15, wherein said switching medium comprises:

at least one switch matrix associated with each said time division, each said switch matrix providing a plurality of output signal paths wherein ones of said signal paths are associated with different antenna beams of a plurality of antenna beams.

17. The system of claim 16, further comprising:

at least one signal combiner associated with said ones of antenna beams of said plurality of antenna beams, wherein said signal combiners are operable to combine signal paths from ones of said switch matrixes to a single output associated with a particular antenna beam of said plurality of antenna beams.

18. The system of claim 14, wherein said power level adjusting means and said selective outputting means are operated under the control of a control processor, said control of said adjusting means and said selective outputting means being substantially synchronous with said time divisions.

19. A system having a plurality of antenna beams for receiving signals associated with time divisions of a time division signal, wherein a predetermined number of said time divisions define a frame, said system comprising:

means for splitting the received signal at ones of said plurality of antenna beams into a number of signals, wherein said number of signals is at least as great as the number of time divisions in said frame;

means associated with each said time division for adjusting the power level of ones of said split signals to result in a desired amplitude during a particular one of said time divisions;

means for providing interruptible signal paths between said signal splitting means and said power level adjusting means, said interruptible signal paths being operable to provide a split signal including a received signal associated with a particular time division to said power level adjusting means associated with the particular time division; and

means for recombining the power level adjusted signals.

20. The system of claim 19, wherein said interruptible signal path means comprises:

at least one switch matrix associated with each said time division, wherein said switch matrix includes an input path associated with each antenna beam and an output path associated with said power level adjustment means associated with the particular time division.

21. The system of claim 19, wherein said power level adjusting means and said interruptible signal path means are operated under the control of a control processor, said control of said adjusting means and said interruptible signal path means being substantially synchronous with said time divisions.

22. A method for providing each signal within a signal component of a plurality of signal components with independent power level adjustment, said method comprising the steps of:

splitting an input signal including said plurality of signal components to provide at least a split signal associated with each said signal component;

adjusting a power level of each said split signals to a predetermined magnitude, said magnitude being maintained throughout said associated signal component, said adjusting step resulting in a power level adjusted signal associated with each split signal wherein said signal within said signal component has said predetermined magnitude; and

switching between each of said power level adjusted signals to produce an output including only said signal components having said predetermined magnitude.

23. The method of claim 22, wherein said signal components are selected from the group of signal components consisting of:

a time division associated with a time division multiple access scheme; and

a signal frequency associated with a frequency division multiple access scheme.

24. The method of claim 22, wherein a predefined number of said signal components comprise a frame.

25. The method of claim 24, wherein said adjusting step comprises the step of adjusting an independently adjustable adjusting means associated with each signal component of said frame of signal components.

26. The method of claim 24, wherein said switching step comprises the step of:

switching an independently switchable switching device associated with each signal component of said frame of signal components.

27. The method of claim 26, wherein at least one of said independently switchable switching devices comprise a multiplexer.

28. The method of claim 22, wherein said switching means is operable to provide a particular signal component to circuitry associated with a select beam of a plurality of radiation beams.

29. The method of claim 28, further comprising the step of:

combining a plurality of input signal paths into at least one output signal path, wherein said input signal paths are associated with said output of said switching step and said at least one signal output path is associated with said particular radiation beam of said plurality of radiation beams.

30. The method of claim 22, wherein said steps are performed substantially concurrently on signal components associated with more than one input signal.

31. The method of claim 30, wherein said more than one input signal includes a first set and a second set of signal components, said first set including signal components associated with a first input signal, and said second set including signal components of a second input signal.

32. An apparatus for independently adjusting a power component of a forward link time division signal frame for each individual receiver communicating through said time division signal frame, wherein each said receiver communicating through said time division signal frame is assigned a particular burst thereof, said apparatus comprising:

a signal splitter having at least one input path and a plurality of output paths, a particular burst of said frame being associated with an output path of said plurality of output paths; and

a plurality of attenuator/amplifiers having an input and an output, ones of said attenuator/amplifiers being coupled to ones of said output paths at said input, each of said attenuator/amplifiers operable to provide an output time division signal having a predetermined magnitude substantially throughout said particular burst associated with said output path.

33. The apparatus of claim 32, further comprising:

a switching device having a plurality of signal in paths and a plurality of signal out paths, said plurality of signal out paths including a plurality of signal out path sets, a particular burst of said frame being associated with a particular signal in path, each signal in path further being associated with a particular signal out path set of said plurality of signal out path sets, ones of said signal in paths being coupled to ones of said attenuator/amplifier outputs, said switching device being operable to direct a select burst of said frame to a particular signal out path.

34. The apparatus of claim 33, wherein said switching device comprises:

a plurality of switches including an independently switchable switch for each signal burst of said frame.

35. The apparatus of claim 33, wherein said switching device comprises a plurality of multiplexers each being associated with a different burst of said frame.

36. The apparatus of claim 33, wherein said switching device comprises a multiplexer having a number of signal in paths at least as great as a number of said bursts in said frame.

37. The apparatus of claim 33, wherein ones of said signal out paths of each signal out path set are associated with a different antenna component having a predefined radiation pattern, said antenna components disposed to provide substantially non-overlapping communication.

38. The apparatus of claim 37, wherein said ones of said signal out paths of each signal out path set associated with a particular antenna component are combined to provide a single input to said antenna component.

39. The apparatus of claim 33, further comprising:

a processor-based controller providing switching information associated with each burst of said frame to said switching device, said information being provided substantially synchronously with said frame of said time division signal propagating through said apparatus.

40. The apparatus of claim 32, further comprising:

a processor-based controller providing power component information associated with each burst of said frame to said plurality of attenuator/amplifiers, said information being provided substantially synchronously with said frame of said time division signal propagating through said apparatus.

41. The apparatus of claim 32, wherein said plurality of attenuator/amplifiers include an independently adjustable attenuator/amplifier for each burst of said frame.

42. An apparatus for independently adjusting a power component of each burst of a plurality of forward link time division signal frames, wherein a first frame of said plurality of frames is associated with a first radio frequency carrier frequency and a second frame of said plurality of frames is associated with a second radio frequency carrier frequency, said apparatus comprising:

a first signal splitter having at least one input path and a plurality of output paths, wherein a particular burst of said first frame is associated with an output path of said plurality of output paths;

a second signal splitter having at least one input path and a plurality of output paths, wherein a particular burst of said second frame is associated with an output path of said plurality of output paths; and

a plurality of attenuator/amplifiers having an input and an output, said plurality of attenuator/amplifiers including a first set of attenuator/amplifiers and a second set of attenuator/amplifiers, wherein ones of said first set of attenuator/amplifiers are coupled to ones of said output paths of said first signal splitter at said input and ones of said second set of attenuator/amplifiers are coupled to ones of said output paths of said second signal splitter as said input, each of said attenuator/amplifiers operable to provide an output time division signal having a predetermined magnitude substantially throughout said particular burst associated with said output path.

43. The apparatus of claim 42, further comprising:

a first switching device set having a plurality of signal in paths and a plurality of signal out paths, said plurality of signal out paths including a first plurality of signal out path sets, a particular burst of said first frame being associated with a particular signal in path, each signal in path further being associated with a particular signal out path set of said first plurality of signal out path sets, ones of said signal in paths being coupled to ones of attenuator/amplifier outputs of said first set of attenuator/amplifiers, said first switching device being operable to direct a select burst of said first frame to a particular signal out path of said first switching device; and

a second switching device set having a plurality of signal in paths and a plurality of signal out paths, said plurality of signal out paths including a second plurality of signal out path sets, a particular burst of said second frame being associated with a particular signal in path, each signal in path further being associated with a particular signal out path set of said second plurality of signal out path sets, ones of said signal in paths being coupled to ones of attenuator/amplifier outputs of said second set of attenuator/amplifiers, said second switching device being operable to direct a select burst of said second frame to a particular signal out path of said second switching device.

44. The apparatus of claim 43, wherein said first and second switching devices comprise:

a plurality of switches including an independently switchable switch for each signal burst of said first and second frame.

45. The apparatus of claim 43, wherein said first and second switching devices comprise a plurality of multiplexers each being associated with a different burst of said first and second frame.

46. The apparatus of claim 43, wherein ones of said signal out paths of each signal out path set are associated with a different antenna component having a predefined radiation pattern, said antenna components disposed to provide substantially non-overlapping communication.

47. The apparatus of claim 46, wherein said ones of said signal out paths of each signal out path set associated with a particular antenna component are combined to provide a single input to said antenna component.

48. The apparatus of claim 43, further comprising:

a processor-based controller providing switching information associated with each burst of said first frame to said first switching device, said information being provided substantially synchronously with said first frame of said time division signal propagating through said apparatus.

49. The apparatus of claim 42, further comprising:

a processor-based controller providing power component information associated with each burst of said first frame to said first set of attenuator/amplifiers, said information being provided substantially synchronously with said first frame of said time division signal propagating through said apparatus.

50. The apparatus of claim 42, wherein said plurality of attenuator/amplifiers include an independently adjustable attenuator/amplifier for each burst of said first and second frame.

51. A system for providing each time division of a frame including a plurality of said time divisions with autonomous power level adjustment, said system comprising:

means for adjusting said power level, said adjusting means including independently adjustable adjusting means for each time division of said frame, each adjusting means being operable to adjust said power level of an input signal to a predetermined magnitude maintained during a respective time division, each adjusting means outputting a power level adjusted signal having said predetermined magnitude at said respective time division;

means for selectively switching between each of said power level adjusted signals, said switching means including an independently switchable switching device for each time division of said frame, said switching means providing a plurality of discrete signal components, each discrete signal component comprising a different one of said respective time divisions;

controller means for controlling adjustment of said adjusting means and switching of said switching means; and

antenna means for transmitting said discrete signal components.

52. The system of claim 51, wherein ones of said plurality of switching devices comprise a multiplexer.

53. The system of claim 51, wherein said antenna means comprise an antenna array adapted to provide a plurality of radiation beams, said antenna array including circuitry adapted to provide directional communication through ones of said plurality of radiation beams.

54. The system of claim 53, wherein said controller means operates to switch said switching means to provide a particular discrete signal component to a portion of said circuitry associated with a predetermined beam of said plurality of radiation beams.

55. The system of claim 54, wherein said circuitry comprises means for combining a plurality of input signal paths into at least one output signal path, wherein said combining means includes at least one signal combiner means associated with a particular radiation beam of said plurality of radiation beams.

56. The system of claim 53, wherein said antenna array comprises an antenna unit for each radiation beam of said plurality of radiation beams.