System and method for increasing throughput in a multiuser detection based multiple access communications system

• US 7,269,223 B2
• Filed: 04/16/2003
• Issued: 09/11/2007
• Est. Priority Date: 04/16/2003
• Status: Active Grant

• Current Assignee: Collision Communications, Inc. (Concert Technology Corporation)
• Original Assignee: BAE Systems Information and Electronic Systems Integration Incorporated (BAE Systems Plc)
• Inventors: Learned, Rachel E., Taylor, Matthew A., MacLeod, Robert B.
• Primary Examiner(s): Ghebretinsae, Temesghen
• Assistant Examiner(s): TORRES, JUAN A
• Application Number:
  US10/414,738
• Publication Number:
  US 20040208251A1
• Time in Patent Office: 1,609 Days
• Field of Search: 375/259, 375/267, 342/361
• US Class Current: 375/259
• CPC Class Codes: H04B 1/7105 Joint detection techniques, e.g. linear detectors
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity

Abstract

The present invention is a digital communication method that increases the overall throughput of a Multiuser Detection (MUD)-based co-channel multiple access (MA) system in terms of the total number of bits transmitted through the shared medium by all the users of the MA system if signals are allowed to interfere. The total number of users can be increased if more dimensions are used for assigning the transmitted signals and the same dimensions are measured at the receiver. Specifically, the present invention does not require any coordination among transmitters but simply requires a transmitter to send its signal with either a randomly chosen polarization ellipse, or an assigned or randomly chosen amplitude level.

Claims

1. A method for increasing the throughput of a multi-user detection-based multiple access communications system, said system comprised of at least one transmitter for transmitting data signals and at least one corresponding receiver, the method comprising the steps of:

representing each signature waveform corresponding to each said transmitted signal as a vector of values dependent upon several parameters;

assigning the value of at least one of said parameters to each said transmitted signal;

transmitting said transmitted signal via a dual polarized transmission antenna;

incorporating a horizontal polarized port and a vertical polarized port in said dual polarized transmission antenna;

receiving said transmitted signals via a dual polarized reception antenna;

incorporating a horizontal polarized port and a vertical polarized port in said dual polarized receiving antenna;

assigning polarization ellipses in a feedback communication loop between a controller and the at least one transmitter;

differentiating between similar signals by detecting each signal'"'"'s set of parameters, both those assigned and those left to physical circumstance; and

jointly detecting data streams associated with each of the signals using a multiuser detection (MUD) processing scheme, the MUD processing scheme having been advantaged by the assignment of said parameters for each transmitted signal.

2. The method of claim 1 wherein the value of said at least one assigned parameter is randomly chosen.

3. The method of claim 1 wherein the value of said at least one assigned parameter is chosen from a predetermined parameter assignment set.

4. The method of claim 1 wherein the value of said at least one assigned parameter is chosen from a set of parameter assignments calculated to be optimal, given the current measurements of received signals, bit error rates, and estimated signal parameters.

5. The method of claim 1 wherein the value of said at least one parameter is varied after a given time interval.

6. The method of claim 1 wherein the value of said at least one parameter is continually varied.

7. The method of claim 1 wherein the value of said at least one assigned parameter is assigned by a centralized controller.

8. The method of claim 1 wherein the value of said at least one assigned parameter is controlled by a centralized controller.

9. The method of claim 1 wherein the value of said at least one assigned parameter is assigned by one of said transmitters.

10. The method of claim 1 wherein the value of said at least one assigned parameter is chosen by each corresponding transmitter according to one of a predetermined rule, set, and algorithm, including a pseudo-random choice.

11. The method of claim 10 wherein the value of said at least one parameter is varied after a given time interval.

12. The method of claim 10 wherein the value of said at least one parameter is continually varied.

13. The method of claim 1 wherein said at least one assigned parameter is a polarization ellipse.

14. The method of claim 1 wherein said at least one assigned parameter is signal amplitude level.

15. A multi-user detection-based multiple access communications system comprising:

at least one transmitter for transmitting signals;

a dual polarized transmission antenna included in each at least one transmitter;

a horizontal polarized port and a vertical polarized port incorporated in said dual polarized transmission antenna;

polarization ellipses in a feedback communication loop between a controller and the at least one transmitter;

means for assigning at least one parameter to each said transmitted signal;

at least one receiver, each said receiver adapted to estimate the signal from said at least one transmitter, wherein each received signature signal corresponding to each said transmitted signal is represented as a vector of values dependent on several parameters;

a dual polarized reception antenna included in each at least one receiver;

a horizontal polarized port and a vertical polarized port incorporated in said dual reception polarized antenna;

means for identifying each said transmitted signal as being distinct from each other said transmitted signal by its said assigned as welt as non-assigned parameters; and

means for detecting all data streams, one stream for each interfering user, wherein a model for each user'"'"'s received signal is employed to advantage the detection.

16. The system of claim 15 wherein the value of said at least one assigned parameter is randomly chosen.

17. The system of claim 15 wherein the value of said at least one assigned parameter is chosen from a predetermined parameter assignment set.

18. The system of claim 15 wherein the value of said at least one assigned parameter is chosen from a set of values calculated to be optimal, given the current measurements of received signals, bit error rates, and estimated signal parameters.

19. The system of claim 15 wherein the value of said at least one parameter is varied after a given time interval.

20. The system of claim 15 wherein the value of said at least one parameter is continuously varied.

21. The system of claim 15 wherein the value of said at least one assigned parameter is assigned by a centralized controller.

22. The system of claim 15 wherein the value of said at least one assigned parameter is controlled by a centralized controller.

23. The system of claim 15 wherein the value of said at least one assigned parameter is assigned by one of said transmitters.

24. The system of claim 15 wherein the value of said at least one assigned parameter is chosen by each corresponding transmitter according to one of a predetermined rule, set, and algorithm, including a pseudo-random choice.

25. The system of claim 24 wherein the value of said at least one parameter is varied after a given time interval.

26. The system of claim 24 wherein the value of said at least one parameter is continuously varied.

27. The system of claim 15 wherein said at least one assigned parameter is a polarization ellipse.

28. The system of claim 15 wherein said at least one assigned parameter is signal amplitude level.

29. A computer readable medium comprising computer instructions for increasing the throughput of a multi-user detection-based multiple access communications system, said system comprised of at least one transmitter for transmitting data signals and at least one corresponding receiver, the computer readable medium comprising instructions for performing the steps of:

representing each signature waveform corresponding to each said transmitted signal as a vector of values dependent upon several parameters;

assigning the value of at least one of these parameters to each said transmitted signal;

transmitting said transmitted signal via a dual polarized transmission antenna;

incorporating a horizontal polarized port and a vertical polarized port in said dual polarized transmission antenna;

assigning polarization ellipses in a feedback communication loop between a controller and the at least one transmitter;

receiving said transmitted signals via a dual polarized reception antenna;

incorporating a horizontal polarized port and a vertical polarized port in said dual polarized receiving antenna;

receiving said transmitted signals;

detecting each signal'"'"'s set of parameters, both those assigned and those left to physical circumstance; and

jointly detecting data streams associated with each of the signals using a multiuser detection (MUD) processing scheme, the MUD processing scheme having been advantaged by the assignment of said parameters for each transmitted signal.

30. The computer readable medium of claim 29 wherein the value of said at least one assigned parameter is randomly chosen.

31. The computer readable medium of claim 29 wherein the value of said at least one assigned parameter is chosen from a predetermined parameter assignment set.

32. The computer readable medium of claim 29 wherein the value of said at least one assigned parameter is chosen from a set of parameter assignments calculated to be optimal, given the current measurements of received signals, bit error rates, and estimated signal parameters.

33. The computer readable medium of claim 29 wherein the value of said at least one parameter is varied after a given time interval.

34. The computer readable medium of claim 29 wherein the value of said at least one parameter is continuously varied.

35. The computer readable medium of claim 29 wherein the value of said at least one assigned parameter is assigned by a centralized controller.

36. The computer readable medium of claim 29 wherein the value of said at least one assigned parameter is controlled by a centralized controller.

37. The computer readable medium of claim 29 wherein the value of said at least one assigned parameter is assigned by one of said transmitters.

38. The computer readable medium of claim 29 wherein the value of said at least one assigned parameter is chosen by each corresponding transmitter according to one of a predetermined rule, set, and algorithm, including a pseudo-random choice.

39. The computer readable medium of claim 38 wherein the value of said at least one parameter is varied after a given time interval.

40. The computer readable medium of claim 38 wherein the value of said at least one parameter is continuously varied.

41. The computer readable medium of claim 29 wherein said at least one assigned parameter is a polarization orientation.

42. The method of claim 29 wherein said at least one assigned parameter is signal amplitude level.

43. A method for increasing the throughput of a multi-user detection-based multiple access communications system, said system comprised of at least one transmitter for transmitting data signals and at least one corresponding receiver, the method comprising the steps of:

representing each signature waveform corresponding to each said transmitted signal as a vector of values dependent upon several parameters;

.

assigning the value of at least one of said parameters to each said transmitted signal;

transmitting said transmitted signal via a dual polarized transmission antenna;

incorporating a horizontal polarized port and a vertical polarized port in said dual polarized transmission antenna;

receiving said transmitted signals via a dual polarized reception antenna;

incorporating a horizontal polarized port and a vertical polarized port in said dual polarized receiving antenna;

instructing the transmitters to choose polarization ellipses at random;

differentiating between similar signals by detecting each signal'"'"'s set of parameters, both those assigned and those left to physical circumstance; and

jointly detecting data streams associated with each of the signals using a multiuser detection (MUD) processing scheme, the MUD processing scheme having been advantaged by the assignment of said parameters for each transmitted signal.

44. A multi-user detection-based multiple access communications system comprising:

at least one transmitter for transmitting signals;

a dual polarized transmission antenna included in each at least one transmitter;

a horizontal polarized port and a vertical polarized port incorporated in said dual polarized transmission antenna;

randomly chosen polarization ellipses in a feedback communication loop between a controller and the at least one transmitter;

means for assigning at least one parameter to each said transmitted signal;

at least one receiver, each said receiver adapted to estimate the signal from said at least one transmitter, wherein each received signature signal corresponding to each said transmitted signal is represented as a vector of values dependent on several parameters;

a dual polarized reception antenna included in each at least one receiver

a horizontal polarized port and a vertical polarized port incorporated in said dual polarized reception antenna;

means for identifying each said transmitted signal as being distinct from each other said transmitted signal by its said assigned as well as non-assigned parameters; and

means for detecting all data streams, one stream for each interfering user, wherein a model for each user'"'"'s received signal is employed to advantage the detection.

45. A computer readable medium comprising computer instructions for increasing the throughput of a multi-user detection-based multiple access communications system, said system comprised of at least one transmitter for transmitting data signals and at least one corresponding receiver, the computer readable medium comprising instructions for performing the steps of:

representing each signature waveform corresponding to each said transmitted signal as a vector of values dependent upon several parameters;

assigning the value of at least one of these parameters to each said transmitted signal;

transmitting said transmitted signal via a dual polarized transmission antenna;

incorporating a horizontal polarized port and a vertical polarized port in said dual polarized transmission antenna;

randomly choosing polarization ellipses in a feedback communication loop between a controller and the at least one transmitter;

receiving said transmitted signals via a dual polarized reception antenna;

incorporating a horizontal polarized port and a vertical polarized port in said dual polarized receiving antenna;

receiving said transmitted signals;

detecting each signal'"'"'s set of parameters, both those assigned and those left to physical circumstance; and

jointly detecting data streams associated with each of the signals using a multiuser detection (MUD) processing scheme, the MUD processing scheme having been advantaged by the assignment of said parameters for each transmitted signal.