PPM RECEIVING SYSTEM AND METHOD USING TIME-INTERLEAVED INTEGRATORS

• US 20050105606A1
• Filed: 11/19/2003
• Published: 05/19/2005
• Est. Priority Date: 11/19/2003
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Hitko, Donald A., Cosand, Albert, Yung, Michael
• Granted Patent: US 7,349,471 B2
• Time in Patent Office: Days
• US Class Current: 375/239
• CPC Class Codes: H03K 9/04 of position-modulated pulses
• CPC Class Codes: H04L 25/4902 Pulse width modulation; Pulse position modulation

Abstract

A communication receiver (30) includes a data receiver (34) that receives a pulse-position modulated signal (38). A clock circuit (70) separates a reference clock signal (36) into multiple coordinating clock signals A, B, and C. Multiple time integrators (78) are gated to generate multiple time-integrated signals in response to the pulse-position modulated signal (38) and the coordinating clock signals A, B, and C. A combiner (96) forms a demodulated signal from the time-integrated signals IntA, IntB, and IntC.

Claims

1. A communication receiver comprising:

a data receiver receiving at least one pulse-position modulated signal;

a clock circuit separating a reference clock signal into a plurality of coordinating clock signals;

a plurality of time integrators gated to generate a plurality of time-integrated signals in response to said at least one pulse-position modulated signal and said plurality of coordinating clock signals; and

a combiner forming a demodulated signal from said plurality of time-integrated signals.

2. A communication receiver as in claim 1 wherein said data receiver comprises at least one electrical transducer.

3. A communication receiver as in claim 2 wherein said at least one electrical transducer comprises at least one photodiode.

4. A communication receiver as in claim 1 further comprising a transimpedance amplifier converting said reference clock signal from being in the form of a current signal into a voltage swing signal.

5. A communication receiver as in claim 1 further comprising a transimpedance amplifier converting said at least one pulse-position modulated signal from being in the form of a current signal into a voltage swing signal.

6. A communication receiver as in claim 1 further comprising a clock receiver receiving said reference clock signal.

7. A communication receiver as in claim 6 wherein said clock receiver comprises at least one electrical transducer.

8. A communication receiver as in claim 7 wherein said at least one electrical transducer comprises at least one photodiode.

9. A communication receiver as in claim 1 further comprising a clock recovery circuit recovering said reference clock signal.

10. A communication receiver as in claim 9 wherein said clock recovery circuit comprises a phase lock loop.

11. A communication receiver as in claim 1 further comprising a one-shot timer circuit widening pulses within said reference clock signal.

12. A communication receiver as in claim 1 further comprising a one-shot timer circuit widening pulses within said at least one pulse-position modulated signal.

13. A communication receiver as in claim 1 further comprising a plurality of switches coupled to said plurality of time integrators, said combiner forming said demodulated signal in response to state of said plurality of switches.

14. A communication receiver as in claim 1 wherein said combiner sums at least a portion of said plurality of time-integrated signals to form said demodulated signal.

15. A communication receiver as in claim 1 wherein said plurality of time integrators are gated to begin integration in response to the plurality of coordinating clock signals.

16. A communication receiver as in claim 1 wherein said plurality of time integrators are gated to cease integration in response to said at least one pulse-position modulated signal.

17. A communication receiver as in claim 1 wherein said plurality of time integrators integrate a constant input value in response to said at least one pulse-position modulated signal and said plurality of coordinating clock signals.

18. A communication receiver as in claim 17 wherein said plurality of time integrators comprise at least one current source providing said constant value.

19. A communication receiver as in claim 1 wherein said plurality of time integrators comprise:

at least one integration switch;

at least one hold switch; and

at least one reset switch.

20. A communication system as in claim 19 wherein said plurality of time integrators perform integration in response to said at least one integration switch.

21. A communication system as in claim 19 wherein said plurality of time integrators hold a voltage value in response to said at least one hold switch.

22. A communication system as in claim 19 wherein said plurality of time integrators reset a voltage value to a nominal value in response to said at least one reset switch.

23. A communication system comprising:

a transmitter generating at least one pulse-position modulated signal; and

a communication receiver comprising;

a data receiver receiving said at least one pulse-position modulated signal;

a clock circuit separating a reference clock signal into a plurality of coordinating clock signals;

a plurality of time integrators gated to generate a plurality of time-integrated signals in response to said at least one pulse-position modulated signal and said plurality of coordinating clock signals; and

a combiner forming a demodulated signal from said plurality of time-integrated signals.

24. A communication receiver as in claim 23 further comprising a clock recovery circuit recovering said reference clock signal.

25. A communication receiver as in claim 23 further comprising a one-shot timer circuit widening pulses within said reference clock signal.

26. A communication system comprising:

a first station having a transmitter generating at least one pulse-position modulated signal; and

a second station having a communication receiver comprising;

a data receiver receiving said at least one pulse-position modulated signal;

a clock circuit separating a reference clock signal into a plurality of coordinating clock signals;

a plurality of time integrators gated to generate a plurality of time-integrated signals in response to said at least one pulse-position modulated signal and said plurality of coordinating clock signals; and

a combiner forming a demodulated signal from said plurality of time-integrated signals.

27. A method of extracting information from pulse-position modulated signals comprising:

receiving at least one pulse-position modulated signal;

separating a reference clock signal into a plurality of clock signals;

gating a plurality of time integrators to generate a plurality of time-integrated signals in response to said at least one pulse-position modulated signal and said plurality of clock signals; and

generating a demodulated signal from said plurality of time-integrated signals.

28. A method as in claim 27 further comprising receiving said reference clock signal.

29. A method as in claim 27 further comprising recovering said reference clock signal from said at least one pulse-position modulated signal.

30. A method as in claim 27 further comprising converting said reference clock signal from a current signal into a voltage swing signal.

31. A method as in claim 27 further comprising converting said at least one pulse-width modulation signal from a current signal into a voltage swing signal.

32. A method as in claim 27 further comprising widening pulses within said reference clock signal.

33. A method as in claim 27 further comprising widening pulses within said at least one pulse-position modulated signal.

34. A method as in claim 27 wherein separating said reference clock signal into a plurality of clock signals comprises generating said plurality of clock signals out-of-phase from each other.

35. A method as in claim 27 wherein gating said plurality of time integrators comprises beginning integration in response to the plurality of coordinating clock signals.

36. A method as in claim 27 wherein gating said plurality of time integrators comprises ceasing integration in response to said at least one pulse-position modulated signal.

37. A method as in claim 27 wherein gating said plurality of time integrators comprises integrating a constant current in response to said at least one pulse-position modulated signal and said plurality of coordinating clock signals.

38. A method of demodulating communication signals comprising:

receiving at least one pulse-position modulated signal;

separating a reference clock signal into a plurality of clock signals;

gating a plurality of time integrators to generate a plurality of time-integrated signals comprising;

beginning integration in response to the plurality of coordinating clock signals;

integrating a constant value; and

ceasing integration in response to said at least one pulse-position modulated signal; and

generating a demodulated signal from said plurality of time-integrated signals.

39. A method as in claim 38 further comprising recovering said reference clock signal.

40. A method as in claim 38 further comprising widening pulses within said reference clock signal.