SIGNAL SEPARATION BASED ON LINEAR INDEPENDENT SIGNAL SUMMATION SETS AND AN ANTENNA ARRAY

• US 20070126632A1
• Filed: 02/07/2007
• Published: 06/07/2007
• Est. Priority Date: 09/23/2004
• Status: Active Grant

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Goldberg, Steven
• Granted Patent: US 7,408,508 B2
• Time in Patent Office: Days
• US Class Current: 342/378
• CPC Class Codes: H04B 7/08 at the receiving station

Abstract

A method for operating a communications device for separating an independent source signal from a mixture of source signals provided by M signal sources includes receiving at an antenna array at least M different summations of the M source signals. The at least M different summations define the mixture of source signals, where N<M. A signal separation processor processes the mixture of source signals by taking samples of the mixture of source signals over time and storing each sample as a data vector to create a data set, and assigning each data vector within the data set to one class within a plurality of classes based on its similarity to other data vectors in the one class. The data vectors assigned to the one class are analyzed to separate the independent source signal from other signals in the mixture of source signals.

Claims

1. A communications device for separating an independent source signal from a mixture of source signals provided by M signal sources, the communications device comprising:

an antenna array comprising N antenna elements for receiving at least M different summations of the M source signals, the at least M different summations defining the mixture of source signals, where N<

M;

a receiver connected to said antenna array for receiving the mixture of source signals; and

a signal separation processor connected to said receiver and configured to

take samples of the mixture of source signals over time and store each sample as a data vector to create a data set;

assign each data vector within the data set to one class within a plurality of classes based on its similarity to other data vectors in the one class; and

analyze the data vectors assigned to the one class to separate the independent source signal from other signals in the mixture of source signals.

2. A communications device according to claim 1 wherein said antenna array comprises a plurality of correlated antenna elements.

3. A communications device according to claim 2 wherein said plurality of correlated antenna elements comprise a plurality of active antenna elements so that said antenna array forms a phased array.

4. A communications device according to claim 2 wherein said plurality of correlated antenna elements comprise an active antenna element and a plurality of passive antenna elements so that said antenna array forms a switched beam antenna.

5. A communications device according to claim 2 wherein at least two of said correlated antenna elements have different polarizations.

6. A communications device according to claim 5 wherein the different polarizations are orthogonal to one another.

7. A communications device according to claim 1 wherein said antenna array forms at least two antenna patterns;

and further comprising a controller connected to said antenna array for selectively forming the at least two antenna patterns; and

wherein said signal separation processor is configured to

determine if the different summations of the at least two source signals are correlated or statistically independent, and if not, then

cooperate with said controller for forming different beams for receiving new different summations of the at least two source signals to replace the different summations of the at least two source signals that are not correlated or statistically independent.

8. A communications device according to claim 1 wherein said antenna array comprises at least one antenna element;

and further comprising;

a respective in-phase and quadrature module connected downstream to each antenna element for separating a respective different summation into an in-phase and quadrature component set, with each in-phase and quadrature component set providing two inputs into said signal separation processor.

9. A communications device according to claim 1 wherein said antenna array comprises at least one antenna element;

and further comprising;

a respective despreader module connected downstream to each antenna element for separating a respective different summation into a K different summation component set, with each different summation including K codes for providing K inputs into said signal separation processor.

10. A method for operating a communications device for separating an independent source signal from a mixture of source signals provided by M signal sources, the communications device comprising an antenna array comprising N antenna elements, a receiver connected to the antenna array, and a signal separation processor connected to the receiver, the method comprising:

receiving at the antenna array at least M different summations of the M source signals, the at least M different summations defining the mixture of source signals, where N<

M;

providing the mixture of source signals to the receiver; and

processing by the signal separation processor the mixture of source signals received by the receiver, the processing comprising

taking samples of the mixture of source signals over time and store each sample as a data vector to create a data set,

assigning each data vector within the data set to one class within a plurality of classes based on its similarity to other data vectors in the one class, and

analyzing the data vectors assigned to the one class to separate the independent source signal from other signals in the mixture of source signals.

11. A method according to claim 10 wherein the antenna array comprises a plurality of correlated antenna elements.

12. A method according to claim 11 wherein the plurality of correlated antenna elements comprise a plurality of active antenna elements so that the antenna array forms a phased array.

13. A method according to claim 11 wherein the plurality of correlated antenna elements comprise an active antenna element and a plurality of passive antenna elements so that the antenna array forms a switched beam antenna.

14. A method according to claim 11 wherein at least two of the correlated antenna elements have different polarizations.

15. A method according to claim 14 wherein the different polarizations are orthogonal to one another.

16. A method according to claim 10 wherein the antenna array forms at least two antenna patterns;

wherein the communications device further comprises a controller connected to the antenna array for selectively forming the at least two antenna patterns; and

the processing further comprising

Determining if the different summations of the at least two source signals are correlated or statistically independent, and if not, then

cooperating with the controller for forming different beams for receiving new different summations of the at least two source signals to replace the different summations of the at least two source signals that are not correlated or statistically independent.

17. A method according to claim 10 wherein the antenna array comprises at least one antenna element;

and wherein the communications device further comprises;

a respective in-phase and quadrature module connected downstream to each antenna element for separating a respective different summation into an in-phase and quadrature component set, with each in-phase and quadrature component set providing two inputs into the signal separation processor.

18. A method according to claim 10 wherein the antenna array comprises at least one antenna element;

and wherein the communications device further comprises;

a respective despreader module connected downstream to each antenna element for separating a respective different summation into a K different summation component set, with each different summation including K codes for providing K inputs into the signal separation processor.