Spectrally efficient high capacity wireless communication systems with spatio-temporal processing

• US 5,828,658 A
• Filed: 10/23/1996
• Issued: 10/27/1998
• Est. Priority Date: 12/12/1991
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: ArrayComm LLC (Ygomi LLC)
• Inventors: Ottersten, Bjorn E., Barratt, Craig H., Parish, David M., Roy, III, Richard H.
• Primary Examiner(s): Nguyen, Chau
• Application Number:
  US08/735,520
• Time in Patent Office: 734 Days
• Field of Search: 370/277, 370/310, 370/334, 370/347, 370/328, 370/329, 370/546, 375/200, 342/386, 342/417, 342/443, 342/444, 364/572, 364/578, 364/581, 455/525, 455/450, 702/179
• US Class Current: 370/310
• CPC Class Codes: G01S 5/12 by co-ordinating position lines of different shape, e.g. hyperbolic, circular, elliptical or radial
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• CPC Class Codes: H01Q 3/2605 Array of radiating elements provided with a feedback control over the element weights, e.g. adaptive arrays
• CPC Class Codes: H01Q 3/267 Phased-array testing or checking devices
• CPC Class Codes: H04B 17/12 of transmit antennas, e.g. of the amplitude or phase
• CPC Class Codes: H04B 17/21 for calibration; for correcting measurements
• CPC Class Codes: H04B 7/0408 using two or more beams, i.e. beam diversity
• CPC Class Codes: H04B 7/0491 using two or more sectors, i.e. sector diversity
• CPC Class Codes: H04B 7/0615 of weighted versions of same signal
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0697 using spatial multiplexing
• CPC Class Codes: H04B 7/0842 Weighted combining
• CPC Class Codes: H04B 7/0845 per branch equalization, e.g. by an FIR-filter or RAKE receiver per antenna branch rake receivers as such H04B1/7115
• 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: H04B 7/0891 Space-time diversity rake receivers H04B1/7115; space-time decoding H04L1/0631
• CPC Class Codes: H04W 16/28 using beam steering
• CPC Class Codes: H04W 72/046 the resource being in the space domain, e.g. beams
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A wireless system includes a network of base stations for receiving uplink signals transmitted from a plurality of remote terminals and for transmitting downlink signals to said plurality of remote terminals using a plurality of channels. A plurality of antenna elements at each base station receives uplink signals, and a plurality of antenna elements at each base station for transmits downlink signals. A signal processor at each base station is connected to the receiving antenna elements and to the transmitting antenna elements for determining spatio-temporal signatures. Spatio-temporal multiplexing and demultiplexing functions are provided for each remote terminal antennae for each channel, and a multiple base station network controller optimizies network performance, whereby communication between the base stations and the plurality of remote terminals in each of the channels can occur simultaneously.

Claims

1. A wireless system for calculating uplink signals transmitted from a plurality of remote terminals using a common uplink channel, said system including at least one base station, said system comprising:

receiving means at said at least one base station including a plurality of antenna elements and receivers for producing measurements of combinations of said uplink signals from said plurality of remote terminals using said common uplink channel;

receive spatio-temporal processing means for determining and storing receive spatio-temporal signatures for said plurality of remote terminals using said measurements; and

spatio-temporal demultiplexing means using said receive spatio-temporal signatures and said measurements to produce separated uplink signals.

3. The wireless system as defined by claim 1 wherein said receive spatio-temporal processing means comprises:

a spatio-temporal signature list comprising a receive spatio-temporal signature for each remote terminal in said plurality of remote terminals and said common uplink channel;

receive spatio-temporal signature determining means for determining said receive spatio-temporal signatures; and

a receive channel selector utilizing said receive spatio-temporal signatures to determine whether said common uplink channel can be further shared by an additional remote terminal.

5. The wireless system as defined by claim 3 wherein said receive spatio-temporal processing means further comprises:

a receive spatio-temporal weight processor for calculating spatio-temporal demultiplexing weights for said plurality of remote terminals, said spatio-temporal demultiplexing weights being utilized by said spatio-temporal demultiplexing means to calculate said uplink signals.

7. The wireless system as defined by claim 5 wherein said receive spatio-temporal processor determines said spatio-temporal demultiplexing weights as the columns of matrix W_rx as follows:

space="preserve" listing-type="equation">W.sub.rx =(.sub.r P.sub.r .sub.r.sup.* +R.sub.nn).sup.-1 .sub.r P.sub.r,

where (·

)^* denotes the complex conjugate transpose of a matrix, (·

)^-1 denotes the inverse of a matrix, R_nn is the noise covariance matrix of said receivers, P_r is a matrix of transmit powers of the remote terminals in said plurality of remote terminals, and _r is a demultiplexing spatio-temporal signature matrix composed of said receive spatio-temporal signatures for said plurality of remote terminals and said common uplink channel.

9. The wireless system as defined by claim 1 wherein said common uplink channel is one of a plurality of uplink channels and wherein said receive spatio-temporal processing means comprises:

an active remote terminal list of remote terminals assigned to at least one channel of said plurality of uplink channels;

a spatio-temporal signature list comprising a receive spatio-temporal signature for each remote terminal of said plurality of remote terminals and each channel of said plurality of said uplink channels;

receive spatio-temporal signature determining means for determining said receive spatio-temporal signatures in said spatio-temporal signature list;

a receive channel selector using said active remote terminal list and said receive spatio-temporal signature list to determine assignments of each remote terminal in said active remote terminal list to at least one of the channels of said plurality of uplink channels; and

a receive spatio-temporal weight processor for calculating spatio-temporal demultiplexing weights for each of the terminals in said active remote terminal list and each channel of said plurality of uplink channels assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal demultiplexing weights being utilized by said spatio-temporal demultiplexing means to calculate said uplink signals.

11. The wireless system as defined by claim 1 wherein said common uplink channel is one of a plurality of uplink channels, said at least one base station is one of a plurality of base stations, said receive spatio-temporal processing means is one of a plurality of receive spatio-temporal processing means, each base station in said plurality of base stations having a corresponding receive spatio-temporal processing means in said plurality of receive spatio-temporal means comprising:

an active remote terminal list comprising a list of remote terminals assigned to at least one channel of said plurality of uplink channels,

a spatio-temporal signature list comprising a receive spatio-temporal signature for each remote terminal of said plurality of remote terminals and each channel of said plurality of uplink channels

receive spatio-temporal signature determining means for determining said receive spatio-temporal signatures in said spatio-temporal signature list, and

a receiver spatio-temporal weight processor for calculating spatio-temporal demultiplexing weights for each of the terminals in said active remote terminal list and each channel of said plurality of uplink channels assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal demultiplexing weights being utilized by said spatio-temporal demultiplexing means to calculate said uplink signals,

said system further comprising;

joint channel selector means for jointly determining assignments of each remote terminal in each said active remote terminal list to at least on of the channels of said plurality of uplink channels and to at least one of base stations of said plurality of base stations, and

communication means for communicating the status of said assignments between each base station in said plurality of base stations and said joint channel selector means.

13. The wireless system as defined by claim 1 and including transmission means comprising a transmitter and an antenna for sending downlink signals from said at least one base station to the terminals in said plurality of remote terminals.

15. The wireless system as defined by claim 1 wherein said spatio-temporal demultiplexing means calculates spatio-temporal demultiplexing weights for said common uplink channel as the columns of a matrix W_rx as follows:

space="preserve" listing-type="equation">W.sub.rx =(.sub.r P.sub.r .sub.r.sup.* +R.sub.nn).sup.-1 .sub.r P.sub.r,

where (·

)^* denotes the complex conjugate transpose of a matrix, (·

)^-1 denotes the inverse of a matrix, R_nn is the noise covariance matrix of said receiver means, P_r is a matrix of transmit powers of the remote terminals in said plurality of remote terminals, and _r is a demultiplexing spatio-temporal signature matrix composed of said receive spatio-temporal signatures for said plurality of remote terminals and said common uplink channel, said spatio-temporal demultiplexing means using said spatio-temporal demultiplexing weights to calculate said uplink signals.

17. The wireless system as defined by claim 1 wherein said uplink signals have predetermined modulation format parameters, and said receive spatio-temporal processing means determines said spatio-temporal demultiplexing weights using said predetermined modulation format parameters of said uplink signals from said plurality of remote terminals.

19. The wireless system as defined by claim 1 wherein said receive spatio-temporal processing means determines said spatio-temporal demultiplexing weights using predetermined calibration signals transmitted by each remote terminal of said plurality of remote terminals.

21. The wireless system as defined by claim 1 wherein said system includes a transponder co-located with each remote terminal of said plurality of remote terminals and wherein said receive spatio-temporal processing means determines said receive spatio-temporal signatures using signals transponded from at least one of the transponders.

23. The wireless system as defined by claim 1 wherein each remote terminal of said plurality of remote terminals includes a transponder and said receive spatio-temporal processing means determines said receive spatio-temporal signatures using signals transponded from at least one of the transponders.

25. The wireless system as defined by claim 1 wherein the location and directivity of said antenna elements are known, and wherein said receive spatio-temporal processing means determines said receive spatio-temporal signatures using the known location and directivity of said antenna elements, and wherein said receive spatio-temporal processing means estimates the directions of arrival of said uplink signals from said plurality of remote terminals.

27. The wireless system as defined by claim 1 wherein the location and directivity of said antenna elements, and the location of said plurality of remote terminals are known and wherein said receive spatio-temporal processing means determines said receive spatio-temporal signatures using the known location and directivity of said antenna elements and the known location of said plurality of remote terminals.

29. The wireless system as defined by claim 1 wherein said uplink signals have predetermined modulation format parameters, and said receive spatio-temporal processing means determines said receive spatio-temporal signatures using said predetermined modulation format parameters of said uplink signals from said plurality of remote terminals.

31. The wireless system as defined by claim 1 wherein said receive spatio-temporal processing means determines said receive spatio-temporal signatures using predetermined calibration signals transmitted by each remote terminal of said plurality of remote terminals.

33. The wireless system as defined by claim 1 further comprising:

transmission means including a plurality of transmit antenna elements and transmitters for transmitting multiplexed downlink signals to said plurality of remote terminals using a common downlink channel,

transmit spatio-temporal processing means for determining and storing transmit spatio-temporal signatures for said plurality of remote terminals, and

spatio-temporal multiplexing means using said transmit spatio-temporal signatures and downlink signals to produce said multiplexed downlink signals.

35. The wireless system as defined by claim 33 wherein said receiving means and said transmission means share common antenna elements using duplexers.

37. The wireless system as defined by claim 33 wherein said receiving means and said transmission means share common antenna elements using transmit/receive switches.

39. The wireless system as defined by claim 33 wherein said common uplink channel is one of a plurality of uplink channels, said common downlink channel is one of a plurality of downlink channels, and wherein said receive spatio-temporal processing means and said transmit spatio-temporal processing means comprises:

an active remote terminal list comprising a list of remote terminals assigned to at least one of the channels of said plurality of uplink channels and remote terminals assigned to at least one of the channels of said plurality of downlink channels,

a spatio-temporal signature list comprising a receive spatio-temporal signature for each remote terminal of said plurality of remote terminals and each channel of said plurality of uplink channels, and a transmit spatio-temporal signature for each remote terminal of said plurality remote terminals and each of channel of said plurality downlink channels,

receive spatio-temporal signature determining means for determining said receive spatio-temporal signatures,

transmit spatio-temporal signature determining means for determining said transmit spatio-temporal signatures, and

a channel selector using said active remote terminal list and said spatio-temporal signature list to determine assignments of each remote terminal of said active remote terminal list to at least one of the channels of said plurality of uplink channels and at least one of the channels of said plurality of downlink channels.

41. The wireless system as defined by claim 39 wherein said receive spatio-temporal processing means and said transmit spatio-temporal processing means further comprise:

a receive spatio-temporal weight processor for calculating spatio-temporal demultiplexing weights for each of the terminals in said active remote terminal list to which an uplink channel is assigned and for each channel of said plurality of uplink channels assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal demultiplexing weights being utilizied by said spatio-temporal demultiplexing means to calculate said uplink signals, and

a transmit spatio-temporal weight processor for calculating spatio-temporal multiplexing weights for each of the terminals in said active remote terminal list to which a downlink channel is assigned and each channel of said plurality of downlink channels assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal multiplexing weights being utilized by said spatio-temporal multiplexing means to produce said multiplexed downlink signals.

43. The wireless system as defined by claim 33 wherein said common uplink channel is one of a plurality of uplink channels, said common downlink channel is one of a plurality of downlink channels, each base station in said plurality of base stations having receive spatio-temporal processing means in said plurality of receive spatio-temporal processing means, each transmit spatio-temporal processing means is one of a plurality of transmit spatio-temporal processing means comprising:

an active remote terminal list comprising a list of remote terminals assigned to at least one of the channels of said plurality of uplink channels and remote terminals assigned to at least one of the channels of said plurality of downlink channels;

a spatio-temporal signature list comprising a receive spatio-temporal signature for each remote terminal of said plurality of remote terminals and each channel of said plurality of uplink channels, and a transmit spatio-temporal signature for each remote terminal of said plurality of remote terminals and each channel of said plurality of down-link channels;

receive spatio-temporal signature determining means for determining said receive spatio-temporal signature;

transmit spatio-temporal signature determining means for determining said transmit spatio-temporal signatures;

a receive spatio-temporal weight processor for calculating spatio-temporal demultiplexing weights for each of the terminals in said active remote terminal list to which an uplink channel is assigned and each channel of said plurality of uplink channels assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal demultiplexing weights being utilized by said spatio-temporal demultiplexing means to calculate said uplink signals; and

a transmit spatio-temporal weight processor for calculating spatio-temporal multiplexing weights for each of the terminals in said active remote terminal list to which a downlink channel is assigned and each channel of said plurality of downlink channels assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal multiplexing weights being utilized by said spatio-temporal multiplexing means to produce said multiplexed downlink signals,

said system further comprising;

joint channel selector means for jointly determining assignments of each remote terminal in each said active remote terminal list to at least one of the channels of said plurality of uplink channels, to at least one of the channels of said plurality of downlink channels and to at least one of the base stations of said plurality of base stations; and

communication means for communicating said assignments between each base station in said plurality of base stations and said joint channel selector means.

45. The wireless system as defined by claim 33 wherein said spatio-temporal multiplexing means determines spatio-temporal multiplexing weight vectors for said common downlink channel as the columns of a matrix W_tx as follows:

space="preserve" listing-type="equation">{W.sub.tx }.sub.k =s.sub.k.sup.t {(.sub.t .sub.t.sup.* .sub.t) .sup.-1 }.sub.mL.sbsb.t.sub.( k-1)+1k=1, . . . ,n.sub.t,

where (·

)^* denotes the complex conjugate transpose of a matrix, (·

)^-1 denotes the inverse of a matrix, {·

}_k denotes the k^th column of a matrix, s_k^t is the amplitude of the k^th said downlink signal, and _t is a multiplexing spatio-temporal signature matrix composed of said transmit spatio-temporal signatures for said plurality of remote terminals and said common downlink channel and wherein said spatio-temporal multiplexing means utilizes said spatio-temporal multiplexing weights to produce said multiplexed downlink signals.

47. The wireless system as defined by claim 33 wherein said downlink signals and said uplink signals are transmitted on the same radio frequency and said transmit spatio-temporal processing means determines said transmit spatio-temporal multiplexing weights directly from the receive spatio-temporal demultiplexing weights.

49. The wireless system as defined by claim 33 wherein said system includes a transponder co-located with each remote terminal of said plurality of remote terminals and wherein said transmit spatio-temporal processing means determines said transmit spatio-temporal signatures using signals transponded from at least one of the transponders.

51. The wireless system as defined by claim 33 wherein each remote terminal in said plurality of remote terminals includes a transponder and wherein said transmit spatio-temporal processing means determines said transmit spatio-temporal signatures using signals transponded from at least one of the transponders.

53. The wireless system as defined by claim 33 wherein the location and directivity of said antenna elements are known, and wherein said transmit spatio-temporal processing means determines said transmit spatio-temporal signatures using the known location and directivity of said antenna elements and estimates of directions of arrival of said uplink signals from said plurality of remote terminals.

54. The wireless system as defined by claim 33 wherein the location and directivity of said antenna elements and location of said plurality of remote terminals are known, and wherein said transmit spatio-temporal processing means determines said transmit spatio-temporal signatures using the known location and directivity of said antenna elements and the known location of said plurality of remote terminals.

57. The wireless system as defined by claim 33 wherein said downlink signals have predetermined modulation format parameters, and said transmit spatio-temporal processing means determines said transmit spatio-temporal signatures using signals transponded from at least one of the transponders.

59. The wireless system as defined by claim 33 wherein said downlink signals have predetermined modulation format parameters, and said transmit spatio-temporal signatures are determined by the corresponding terminals in said plurality of remote terminals using the predetermined modulation format parameters of said downlink signals.

60. The wireless system as defined by claim 33 wherein said downlink signals and said uplink signals are transmitted on the same radio frequency and said transmit spatio-temporal processing means determines said transmit spatio-temporal signatures by calculating them directly from said receive spatio-temporal signatures.

2. In a wireless system a method for calculating uplink signals transmitted from a plurality of remote terminals using a common uplink channel, said system including at least one base station, said at least one base station including a plurality of antenna elements and receivers for producing measurements of combinations of said uplink signals from said plurality of remote terminals using said common uplink channel, said method comprising the steps of:

receiving at the receivers of said at least one base station measurements of combinations of said uplink signals from said plurality of remote terminals using said common uplink channel;

receive spatio-temporal processing for determining and storing receive spatio-temporal signatures for said plurality of remote terminals using said measurements; and

spatio-temporal demultiplexing using said receive spatio-temporal signatures and said measurements to produce separated uplink signals.

4. The method defined by claim 2 wherein said receive spatio-temporal processing further comprises:

determining a receive spatio-temporal signature for each remote terminal in said plurality of remote terminals and said common uplink channel;

forming a spatio-temporal signature list comprising said receive spatio-temporal signatures; and

channel selecting utilizing said receive spatio-temporal signatures to determine whether said common uplink channel can be further shared by an additional remote terminal.

6. The method as defined by claim 4 wherein said receive spatio-temporal processing further comprises:

receive spatio-temporal weight processing for determining spatio-temporal demultiplexing weights for said plurality of remote terminals, said spatio-temporal demultiplexing weights being utilized by said spatio-temporal demultiplexing step to calculate said uplink signals.

8. The method as defined by claim 6 wherein said receive spatio-temporal processing step determines said spatio-temporal demultiplexing weights as the columns of matrix W_rx as follows:

space="preserve" listing-type="equation">W.sub.rx =(.sub.r P.sub.r .sub.r.sup.* +R.sub.nn).sup.-1 .sub.r P.sub.r,

where (·

)^* denotes the complex conjugate transpose of a matrix, (·

)^-1 denotes the inverse of a matrix, R_nn is the noise covariance matrix of said receivers, P_r is a matrix of transmit powers of the remote terminals in said plurality of remote terminals, and _r is a demultiplexing spatio-temporal signature matrix composed of said receive spatio-temporal signatures for said plurality of remote terminals and said common uplink channel.

10. The method as defined by claim 2 wherein said common uplink channel is one of a plurality of uplink channels and wherein said receive spatio-temporal processing step further comprises:

determining a receive spatio-temporal signature for each remote terminal of said plurality of remote terminals and each channel of said plurality of said uplink channels;

forming an active remote terminal list of remote terminals assigned to at least one channel of said plurality of uplink channels;

forming a spatio-temporal signature list comprising said receive spatio-temporal signatures;

receive channel selecting using said active remote terminal list and said receive spatio-temporal signature list to determine assignments of each remote terminal in said active remote terminal list to at least one of the channels of said plurality of uplink channels; and

receive spatio-temporal weight processing for determining spatio-temporal demultiplexing weights for each of the terminals in said active remote terminal list and each channel of said plurality of uplink channels assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal demultiplexing weights being utilized by said spatio-temporal demultiplexing step to calculate said uplink signals.

12. The method as defined by claim 2 wherein said common uplink channel is one of a plurality of uplink channels, said at least one base station is one of a plurality of base stations, said method further comprising:

forming an active remote terminal list comprising a list of remote terminals assigned to at least one channel of said plurality of uplink channels;

determining a receive spatio-temporal signature for each remote terminal of said plurality of remote terminals and each channel of said plurality of uplink channels;

forming a spatio-temporal signature list comprising said receive spatio-temporal signatures;

receiver spatio-temporal weight processing for determining the spatio-temporal demultiplexing weights for each of the terminals in said active remote terminal list and each channel of said plurality of uplink channels assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal demultiplexing weights being utilized by said spatio-temporal demultiplexing step to calculate said uplink signals;

joint channel selecting for jointly determining assignments of each remote terminal in each said active remote terminal list to at least on of the channels of said plurality of uplink channels and to at least one of base stations of said plurality of base stations; and

communicating the status of said assignments between each base station in said plurality of base stations.

14. The method as defined by claim 2 further including sending downlink signals from said at least one base station to the terminals in said plurality of remote terminals.

16. The method as defined by claim 2 wherein said spatio-temporal demultiplexing calculates spatio-temporal demultiplexing weights for said common uplink channel as the columns of a matrix W_rx as follows:

space="preserve" listing-type="equation">W.sub.rx =(.sub.r P.sub.r .sub.r.sup.* +R.sub.nn).sup.-1 .sub.r P.sub.r,

where (·

)^* denotes the complex conjugate transpose of a matrix, (·

)^-1 denotes the inverse of a matrix, R_nn is the noise covariance matrix of said receivers, P_r is a matrix of transmit powers of the remote terminals in said plurality of remote terminals, and _r is a demultiplexing spatio-temporal signature matrix composed of said receive spatio-temporal signatures for said plurality of remote terminals and said common uplink channel, said spatio-temporal demultiplexing method using said spatio-temporal demultiplexing weights to calculate said uplink signals.

18. The method as defined by claim 2 wherein said uplink signals have predetermined modulation format parameters, and wherein said receive spatio-temporal processing step determines said spatio-temporal demultiplexing weights using said predetermined modulation format parameters of said uplink signals from said plurality of remote terminals.

20. The method as defined by claim 2 wherein said receive spatio-temporal processing step determines said spatio-temporal demultiplexing weights using predetermined calibration signals transmitted by each remote terminal of said plurality of remote terminals.

22. The method as defined by claim 2 wherein said system includes a transponder co-located with each remote terminal of said plurality of remote terminals, said method includes transponding signals received at least one of said remote terminals, and wherein said receive spatio-temporal processing step determines said receive spatio-temporal signatures using said transponded signals.

24. The method as defined by claim 2 wherein each remote terminal of said plurality of remote terminals includes a transponder, said method includes transponding signals received at least one of said remote terminals, and said receive spatio-temporal processing step determines said receive spatio-temporal signatures using said transponded signals.

26. The method as defined by claim 2 wherein the location and directivity of said antenna elements are known, and wherein said receive spatio-temporal processing step determines said receive spatio-temporal signatures using the known location and directivity of said antenna elements, and wherein said receive spatio-temporal processing step estimates the directions of arrival of said uplink signals from said plurality of remote terminals.

28. The method as defined by claim 2 wherein the location and directivity of said antenna elements, and the location of said plurality of remote terminals are known, and wherein said receive spatio-temporal processing step determines said receive spatio-temporal signatures using the known location and directivity of said antenna elements and the known location of said plurality of remote terminals.

30. The method as defined by claim 2 wherein said uplink signals have predetermined modulation format parameters, and wherein said receive spatio-temporal processing step determines said receive spatio-temporal signatures using said predetermined modulation format parameters of said uplink signals from said plurality of remote terminals.

32. The method as defined by claim 2 wherein said receive spatio-temporal processing step determines said receive spatio-temporal signatures using predetermined calibration signals transmitted by each remote terminal of said plurality of remote terminals.

34. The method as defined by claim 2, wherein said system further comprises a plurality of transmit antenna elements and transmitters for transmitting multiplexed downlink signals to said plurality of remote terminals using a common downlink channel, the method further comprising:

transmitting the multiplexed downlink signals to said plurality of remote terminals using a common downlink channel,

transmit spatio-temporal processing for determining and storing transmit spatio-temporal signatures for said plurality of remote terminals, and

spatio-temporal multiplexing using said transmit spatio-temporal signatures and downlink signals to produce said multiplexed downlink signals.

36. The method as defined by claim 34 further comprising sharing common antenna elements for said receivers and said transmitters using duplexers.

38. The method as defined by claim 34 further comprising switching common antenna elements between said receivers and said transmitters.

40. the method as defined by claim 34 wherein said common uplink channel is one of a plurality of uplink channels, said common downlink channel is one of a plurality of downlink channels, wherein said receive spatio-temporal processing step and said transmit spatio-temporal processing step further comprise:

forming an active remote terminal list comprising a list of remote terminals assigned to at least one of the channels of said plurality of uplink channels and remote terminals assigned to at least one of the channels of said plurality of downlink channels;

determining as part of said receive spatio-temporal processing step a receive spatio-temporal signature for each remote terminal of said plurality of remote terminals and each channel of said plurality of uplink channels;

determining as part of said transmit spatio-temporal processing step a transmit spatio-temporal signature for each remote terminal of said plurality remote terminals and each of channel of said plurality downlink channels;

forming a spatio-temporal signature list comprising the determined receive spatio-temporal signatures and the determined transmit spatio-temporal signatures; and

channel selecting using said active remote terminal list and said spatio-temporal signature list to determine assignments of each remote terminal of said active remote terminal list to at least one of the channels of said plurality of uplink channels and at least one of the channels of said plurality of downlink channels.

42. The method as defined by claim 40 wherein said receive spatio-temporal processing step and said transmit spatio-temporal processing step further comprise:

receive spatio-temporal weight processing for determining spatio-temporal demultiplexing weights for each of the terminals in said active remote terminal list to which an uplink channel is assigned and for each channel of said plurality of uplink channels assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal demultiplexing weights being utilized by said spatio-temporal demultiplexing step to calculate said uplink signals; and

transmit spatio-temporal weight processing for determining spatio-temporal multiplexing weights for each of the terminals in said active remote terminal list to which a downlink channel is assigned and each channel of said plurality of downlink channels assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal multiplexing weights being utilized by said spatio-temporal multiplexing step to produce said multiplexed downlink signals.

44. The method as defined by claim 34 wherein said common uplink channel is one of a plurality of uplink channels, said common downlink channel is one of a plurality of downlink channels, each base station in said plurality of base stations carrying out said receive spatio-temporal processing step and said transmit spatio-temporal processing step, wherein said receive spatio-temporal processing step and said transmit spatio-temporal processing step further comprise:

forming an active remote terminal list comprising a list of remote terminals assigned to at least one of the channels of said plurality of uplink channels and remote terminals assigned to at least one of the channels of said plurality of downlink channels;

determining as part of said receive spatio-temporal processing step a receive spatio-temporal signature for each remote terminal of said plurality of remote terminals and each channel of said plurality of uplink channels;

determining as part of said transmit spatio-temporal processing step a transmit spatio-temporal signature for each remote terminal of said plurality remote terminals and each of channel of said plurality downlink channels;

forming a spatio-temporal signature list comprising the determined receive spatio-temporal signatures and the determined transmit spatio-temporal signatures; and

receive spatio-temporal weight processing for determining spatio-temporal demultiplexing weights for each of the terminals in said active remote terminal list to which an uplink channel is assigned and each channel of said plurality of uplink channels assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal demultiplexing weights being utilized by said spatio-temporal demultiplexing step to calculate said uplink signals;

transmit spatio-temporal weight processing for determining spatio-temporal multiplexing weights for each of the terminals in said active remote terminal list to which a downlink channel is assigned and each channel of said plurality of downlink channels assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal multiplexing weights being utilized by said spatio-temporal multiplexing step to produce said multiplexed downlink signals;

joint channel selecting channel for jointly determining assignments of each remote terminal in each said active remote terminal list to at least one of the channels of said plurality of uplink channels, to at least one of the channels of said plurality of downlink channels and to at least one of the base stations of said plurality of base stations; and

communicating said determined assignments between each base station in said plurality of base stations.

46. The method as defined by claim 34 wherein said spatio-temporal multiplexing step determines spatio-temporal multiplexing weight vectors for said common downlink channel as the columns of a matrix W_tx as follows:

space="preserve" listing-type="equation">{W.sub.tx }.sub.k =s.sub.k.sup.t {(.sub.t .sub.t.sup.* .sub.t) .sup.-1 }.sub.mL.sbsb.t.sub.( k-1)+1k=1, . . . ,n.sub.t,

where (·

)^* denotes the complex conjugate transpose of a matrix, (·

)^-1 denotes the inverse of a matrix, {·

}_k denotes the k^th column of a matrix, s_k^t is the amplitude of the k^th said downlink signal, and _t is a multiplexing spatio-temporal signature matrix composed of said transmit spatio-temporal signatures for said plurality of remote terminals and said common downlink channel and wherein said spatio-temporal multiplexing method utilizes said spatio-temporal multiplexing weights to produce said multiplexed downlink signals.

48. The method as defined by claim 34 wherein said downlink signals and said uplink signals are transmitted on the same radio frequency and said transmit spatio-temporal processing step determines said transmit spatio-temporal multiplexing weights directly from the receive spatio-temporal demultiplexing weights.

50. The method as defined by claim 34 wherein said system includes a transponder co-located with each remote terminal of said plurality of remote terminals, said method includes transponding signals received at least one of said remote terminals, and wherein said transmit spatio-temporal processing step determines said transmit spatio-temporal signatures using said transponded signals.

52. The method as defined by claim 34 wherein each remote terminal in said plurality of remote terminals includes a transponder, said method includes transponding signals received at least one of said remote terminals, and wherein said transmit spatio-temporal processing step determines said transmit spatio-temporal signatures using said transponded signals.

55. The method as defined by claim 34 wherein the location and directivity of said antenna elements and location of said plurality of remote terminals are known, and wherein said transmit spatio-temporal processing step determines said transmit spatio-temporal signatures using the known location and directivity of said antenna elements and the known location of said plurality of remote terminals.

56. The method as defined by claim 34 wherein the location and directivity of said antenna elements are known, and wherein said transmit spatio-temporal processing step determines said transmit spatio-temporal signatures using the known location and directivity of said antenna elements and estimates of directions of arrival of said uplink signals from said plurality of remote terminals.

58. The method as defined by claim 34 wherein said downlink signals have predetermined modulation format parameters, and said transmit spatio-temporal processing step determines said transmit spatio-temporal signatures using said transponded signals.

61. The method as defined by claim 34 wherein said downlink signals and said uplink signals are transmitted on the same radio frequency and said transmit spatio-temporal processing step determines said transmit spatio-temporal signatures by calculating them directly from said receive spatio-temporal signatures.

62. A wireless system including at least one base station for transmitting to a plurality of remote terminals using a common downlink channel, said system comprising:

transmission means at said at least one base station including a plurality of transmit antenna elements and transmitters for transmitting multiplexed downlink signals to said plurality of remote terminals;

transmit spatio-temporal processing means for determining and storing transmit spatio-temporal signatures for said plurality of remote terminals; and

spatio-temporal multiplexing means using said transmit spatio-temporal signatures and downlink signals to produce said multiplexed downlink signals,

whereby said at least one base station can transmit said downlink signals to said plurality of remote terminals simultaneously on a common downlink channel.

64. The wireless system as defined by claim 62 wherein said common downlink channel is one of a plurality of downlink channels and wherein said transmit spatio-temporal processing means comprises:

a active remote terminal list comprising a list of remote terminals assigned to at least one of the channels of said plurality of downlink channels;

a spatio-temporal signature list comprising a transmit spatio-temporal signature for each remote terminal of said plurality of remote terminals and each channel of said plurality of downlink channels;

transmit spatio-temporal signature determining means for determining said transmit spatio-temporal signatures; and

a transmit channel selector using said active remote terminal list and said spatio-temporal signature list to determine assignments of each remote terminal in said active remote terminal list to at least one of the channels of said plurality of downlink channels.

66. The wireless system as defined by claim 64 wherein said transmit spatio-temporal processing means further comprises:

a transmit spatio-temporal weight processor for calculating spatio-temporal multiplexing weights for each of the terminals in said active remote terminal list to which a downlink channel is assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal multiplexing weights being utilized be said spatio-temporal multiplexing means to produce said multiplexed downlink signals.

68. The wireless system as defined by claim 62 wherein said at least one base station is one of a plurality of base stations, said common downlink channel is one of a plurality of downlink channels, each base station in said plurality of base stations having a transmit spatio-temporal processing means in said plurality of transmit spatio-temporal processing means, comprising:

an active remote terminal list comprising a list of remote terminals assigned to at least one of the channels of said plurality of downlink channels;

a spatio-temporal signature list comprising a transmit spatio-temporal signature for each remote terminal of said plurality of remote terminals and each channel of said plurality of downlink channels;

transmit spatio-temporal signature determining means for determining said transmit spatio-temporal signatures; and

a transmit spatio-temporal weight processor for calculating spatio-temporal multiplexing weights for each of the terminals in said active remote terminal list to which a downlink channel is assigned and each channel of said plurality of downlink channels assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal multiplexing weights being utilized by said spatio-temporal multiplexing means to produce said multiplexed downlink signals,

said system further comprising;

joint channel selector means for jointly determining assignments of each remote terminal in said active remote terminal list to at least one of the channels of said plurality of downlink channels and to at least one of the base stations of said plurality of base stations; and

communications means for communicating said assignments between each base station in said plurality of base stations and said joint channel selector means.

70. The wireless system as defined by claim 62 wherein said spatio-temporal multiplexing means determines spatio-temporal multiplexing weight vectors for said common downlink channel as the columns of a matrix W_tx as follows:

space="preserve" listing-type="equation">{W.sub.tx }.sub.k =s.sub.k.sup.t {.sub.t .sub.t.sup.* .sub.t) .sup.-1 }.sub.mL.sbsb.t.sub.(k-1)+1 k=1, . . . ,n.sub.t,

where (·

)^* denotes the complex conjugate transpose of a matrix, (·

)^-1 denotes the inverse of a matrix, {·

}_k denotes the k^tl column of a matrix, s_k^t is the amplitude of the k^th said downlink signal, and _t is a multiplexing spatio-temporal signature matrix composed of said transmit spatio-temporal signatures for said plurality of remote terminals and said common downlink channel and said spatio-temporal multiplexing means utilizes said spatio-temporal multiplexing weights to produce said multiplexed downlink signals.

72. The wireless system as defined by claim 62 wherein said system includes a transponder co-located with each remote terminal of said plurality of remote terminals and wherein said transmit spatio-temporal processing means determines said transmit spatio-temporal signatures using signals transponded from at least one of the transponders.

74. The wireless system as defined by claim 62 wherein each remote terminal in said plurality of remote terminals includes a transponder, and wherein said transmit spatio-temporal processing means determines said transmit spatio-temporal signatures using signals transponded from at least one of the transponders.

76. The wireless system as defined by claim 62 wherein said downlink signals have predetermined modulation format parameters, and said transmit spatio-temporal processing means determines said transmit spatio-temporal signatures using signals transponded from at least one of the transponders.

78. The wireless system as defined by claim 62 wherein said downlink signals have predetermined modulation format parameters, and said transmit spatio-temporal signatures are determined by the corresponding terminals in said plurality of remote terminals using the predetermined modulation format parameters of said downlink signals.

79. The wireless system as defined by claim 62 wherein the location and directivity of said antenna elements and the location of said plurality of remote terminals are known, and wherein said transmit spatio-temporal processing means determines said transmit spatio-temporal signatures using the known location and directivity of said antenna elements and the known location of said plurality of remote terminals.

63. In a wireless system including at least one base station, said at least one base station including a plurality of transmit antenna elements and transmitters, the method for transmitting to a plurality of remote terminals using a common downlink channel, said method comprising:

transmitting multiplexed downlink signals to said plurality of remote terminals using said transmitters at said at least one base station;

transmit spatio-temporal processing for determining and storing transmit spatio-temporal signatures for said plurality of remote terminals; and

spatio-temporal multiplexing using said transmit spatio-temporal signatures and downlink signals to produce said multiplexed downlink signals.

65. The method as defined by claim 63 wherein said common downlink channel is one of a plurality of downlink channels and wherein said transmit spatio-temporal processing step comprises:

forming a active remote terminal list comprising a list of remote terminals assigned to at least one of the channels of said plurality of downlink channels;

determining a transmit spatio-temporal signature for each remote terminal of said plurality of remote terminals and each channel of said plurality of downlink channels;

forming a spatio-temporal signature list comprising the transmit spatio-temporal signatures; and

transmit channel selecting using said active remote terminal list and said spatio-temporal signature list to determine assignments of each remote terminal in said active remote terminal list to at least one of the channels of said plurality of downlink channels.

67. the method as defined by claim 65 wherein said transmit spatio-temporal processing step further comprises:

transmit spatio-temporal weight processing for determining spatio-temporal multiplexing weights for each of the terminals in said active remote terminal list to which a downlink channel is assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal multiplexing weights being utilized he said spatio-temporal multiplexing step to produce said multiplexed downlink signals.

69. The method as defined by claim 63 wherein said at least one base station is one of a plurality of base stations, said common downlink channel is one of a plurality of downlink channels, each base station in said plurality of base stations carrying out said transmit spatio-temporal processing step, said transmit spatio-temporal processing step comprising:

forming an active remote terminal list comprising a list of remote terminals assigned to at least one of the channels of said plurality of downlink channels, determining a transmit spatio-temporal signature for each remote terminal of said plurality of remote terminals and each channel of said plurality of downlink channels;

forming a spatio-temporal signature list comprising the transmit spatio-temporal signatures;

transmit spatio-temporal weight processing for determining spatio-temporal multiplexing weights for each of the terminals in said active remote terminal list to which a downlink channel is assigned and each channel of said plurality of downlink channels assigned to at least one of the terminals in said active remote terminal list, said spatio-temporal multiplexing weights being utilized by said spatio-temporal multiplexing step to produce said multiplexed downlink signals;

joint channel selecting for jointly determining assignments of each remote terminal in said active remote terminal list to at least one of the channels of said plurality of downlink channels and to at least one of the base stations of said plurality of base stations; and

communicating said determined assignments between each base station in said plurality of base stations.

71. The method as defined by claim 63 wherein said spatio-temporal multiplexing step determines spatio-temporal multiplexing weight vectors for said common downlink channel as the columns of a matrix W_tx as follows:

space="preserve" listing-type="equation">{W.sub.tx }.sub.k =s.sub.k.sup.t {.sub.t .sub.t.sup.* .sub.t) .sup.-1 }.sub.mL.sbsb.t.sub.(k-1)+1 k=1, . . . ,n.sub.t,

where (·

)^* denotes the complex conjugate transpose of a mathrix, (·

)^-1 denotes the inverse of a matrix, {·

}_k denotes the k^th column of a matrix, s_k^t is the amplitude of the k^th said downlink signal, and _t is a multiplexing spatio-temporal signature matrix composed of said transmit spatio-temporal signatures for said plurality of remote terninals and said common downlink channel and said spatio-temporal multiplexing method utilizes said spatio-temporal multiplexing weights to produce said multiplexed downlink signals.

73. The method as defined by claim 63 wherein said system includes a transponder co-located with each remote terminal of said plurality of remote terminals, said method includes transponding the signals received at at least one remote terminal, and wherein said transmit spatio-temporal processing step determines said transmit spatio-temporal signatures using the transponded signals.

75. The method as defined by claim 63 wherein each remote terminal in said plurality of remote terminals includes a transponder, said method includes transponding the signals received at at least one remote terminal, and wherein said transmit spatio-temporal processing step determines said transmit spatio-temporal signatures using the transponded signals.

77. The method as defined by claim 63 wherein said downlink signals have predetermined modulation format parameters, and said transmit spatio-temporal processing step determines said transmit spatio-temporal signatures using the transmitted signals.

80. The method as defined by claim 63 wherein the location and directivity of said antenna elements and the location of said plurality of remote terminals are known, and wherein said transmit spatio-temporal processing step determines said transmit spatio-temporal signatures using the known location and directivity of said antenna elements and the known location of said plurality of remote terminals.