Cooperative mobile antenna system

• US 20010033248A1
• Filed: 02/28/2001
• Published: 10/25/2001
• Est. Priority Date: 02/29/2000
• Status: Active Grant

• Current Assignee: HRL Laboratories LLC (The Boeing Co.)
• Original Assignee: HRL Laboratories LLC (The Boeing Co.)
• Inventors: Owechko, Yuri
• Granted Patent: US 6,642,887 B2
• Time in Patent Office: Days
• US Class Current: 342/371
• 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: H04B 7/024 Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems

Abstract

An adaptive antenna beamformer is presented, said beamformer including a first signal source 100 and a second signal source 102 and an ambient noise or other interfering signals source 106, which are exposed to an antenna array 104. The mixed signals 108 are provided to a blind source separation processor 110. The blind separation processor 110, in this case an Independent Component Analysis element, is comprised of a group of processes that are configured to separate mixtures of signals blindly. The blind separation processor 110, provides three outputs, a first signal output 112, a second signal output 114, and a third signal output 116. The signal outputs each correspond to their respective signal input.

Claims

1. A cooperative mobile antenna apparatus comprising:

i. a first plurality of local nodes configured to receive and transmit electromagnetic radiation on at least one channel;

ii. a blind source separation element operatively interconnected to the first plurality of local nodes; and

iii. a host node configured to receive and transmit electromagnetic radiation on at least one channel, wherein the electromagnetic radiation includes a reference signal, where the host node is communicatively linked with the plurality of local nodes;

wherein the host node is configured to send a training or reference signal to the first plurality of local nodes; and

wherein the first plurality of local nodes are configured to utilize the training or reference signal as a means for configuring the blind source separation unit so that the nodes can separate incoming signals and selectively isolate the incoming signals from the host node and directionally transmit data signals to and receive data signals from the host node utilizing blind beamforming techniques.

2. A cooperative mobile antenna apparatus as set forth in

claim 1

, wherein the first plurality of local nodes are organized into a configuration selected from the group consisting of an organized static array, an organized dynamic array, a random static array, and a random dynamic array, and wherein the first plurality of local nodes may transition from one configuration to another in real time.

3. A cooperative mobile antenna apparatus as set forth in

claim 1

, wherein the host node is locally interfaced with a second plurality of nodes, and one of the first plurality of local nodes serves as a host node to the second plurality nodes.

4. A cooperative mobile antenna apparatus as set forth in

claim 1

, wherein the blind source separation element is comprised of a joint approximate diagonalization of eigenmatrices independent component analysis algorithm.

5. A cooperative mobile antenna apparatus as set forth in

claim 1

, wherein the identified and selectively isolated signals are routed to appropriate destinations within the first plurality of local nodes.

6. A cooperative mobile antenna apparatus as set forth in

claim 1

, wherein when the local nodes are transmitting, the separate data channels are routed to the proper nodes from the blind source separation along with correct antenna coefficients.

7. A cooperative mobile antenna apparatus as set forth in

claim 1

, wherein the overhead costs for the local communication between the first plurality of local nodes is over relatively short distances.

8. A cooperative mobile antenna apparatus as set forth in

claim 7

, wherein the first plurality of nodes communicate with one another and each node sends messages only to its nearest neighbors.

9. A cooperative mobile antenna apparatus as set forth in

claim 1

, wherein the reference signal is utilized to optimize the performance of the Blind Source Separation processor;

and

wherein a plurality of beamforming coefficients are developed by the first plurality of local nodes using the reference signal, and

wherein the plurality of beamforming coefficients are utilized by the first plurality of local nodes to form a virtual antenna array;

whereby the first plurality local nodes directionally receive or transmit electromagnetic radiation.

10. A cooperative mobile antenna apparatus as set forth in

claim 1

, wherein, the reference signal is optimized, such that the Blind Source Separation processor can achieve convergence quickly;

and

whereby the first plurality of local nodes can adapt to changing reception patterns and relative motion effects quickly.

11. A cooperative mobile antenna apparatus as set forth in

claim 1

, wherein electromagnetic radiation containing data signal is transmitted and received until the quality of the data signals drops below a predefined threshold, at which time a new reference signal is transmitted.

12. A cooperative mobile antenna apparatus as set forth in

claim 1

, wherein the reference signal is optimized, to facilitate the rapid convergence in the blind source separation element;

whereby the blind source separation element can adapt to changed communication channels and relative motion effects very quickly.

13. A cooperative mobile antenna apparatus as set forth in

claim 12

, wherein the optimization of the reference signals involves satisfying a number of criteria, including at least one of the following:

i. ensuring that the reference signals experiences the same environmental conditions as the data signals;

ii. providing reference signals that are statistically independent;

iii. providing reference signals that have nonzero kurtosis;

iv. providing reference signals that are locally stationary in the statistical sense;

v. providing reference signals that have low bandwidth requirements.

14. A method for forming a virtual antenna array comprising:

i. providing a first plurality of local nodes configured to receive and transmit electromagnetic radiation;

ii. providing a host node configured to receive and transmit electromagnetic radiation;

iii. providing a blind source separation element operatively interconnected to the plurality of local nodes;

wherein the host node is configured to send a training or reference signal to the plurality of local nodes; and

wherein the first plurality of local nodes are configured to utilize the training or reference signal as a means for determining their orientation and position relative to the host node so that they can identify and selectively isolate incoming signals from the host node and transmit to the host node utilizing beamforming techniques.

15. A method for forming a virtual antenna array as set forth in

claim 14

, wherein the first plurality of local nodes are organized, at any given time interval, in one of the following manners:

i. an organized static array;

ii. an organized dynamic array;

iii. a random static array;

iv. a random dynamic array;

wherein the dynamic arrays may transition from organized to random or from random to organized in real time.

16. A method for forming a virtual antenna array as set forth in

claim 14

, wherein the host node is locally interfaced with a second plurality of nodes, and one of the first plurality of local nodes serves as a host node to the second plurality nodes.

17. A method for forming a virtual antenna array as set forth in

claim 14

, wherein the blind source separation element is comprised of a joint approximate diagonalization of eigenmatrices independent component analysis algorithm.

18. A method for forming a virtual antenna array as set forth in

claim 14

, wherein the identified and selectively isolated signals are routed to appropriate destinations within the first plurality of local nodes.

19. A method for forming a virtual antenna array as set forth in

claim 14

, wherein when the local nodes are transmitting;

the separate data channels are routed to the proper nodes from the blind source separation along with correct antenna coefficients.

20. A method for forming a virtual antenna array as set forth in

claim 14

, wherein the overhead costs for the local communication between the a first plurality of local nodes are small because the communication is over relatively short distances.

21. A method for forming a virtual antenna array as set forth in

claim 20

, wherein node-to-node propagation communication is employed for the local communication among the a first plurality of local nodes, wherein each node sends messages only to its nearest neighbors.

22. A method for forming a virtual antenna array as set forth in

claim 14

, wherein the reference signal is utilized to optimize the performance of the blind source separation element and wherein a plurality of beamforming coefficients for a virtual antenna array formed by the first plurality of local nodes using the reference signal, can then be used to transmit or receive information-bearing signals.

23. A method for forming a virtual antenna array as set forth in

claim 14

, wherein, by utilizing optimized reference signals, and the blind source separation element can converge using a relatively small number of samples and therefore can adapt to changing reception patterns and relative motion effects very quickly.

24. A method for forming a virtual antenna array as set forth in

claim 14

, wherein information signals are transmitted and received until the quality of signal drops below a predefined level at which time a new reference signal block is sent.

25. A method for forming a virtual antenna array as set forth in

claim 14

, wherein the reference signal is optimized, to facilitate the rapid convergence of the blind source separation element;

whereby the blind source separation algorithm can adapt to changing communication channels and relative motion effects very quickly.

26. A method for forming a virtual antenna array as set forth in

claim 25

, wherein the optimization of the reference signals involves satisfying a number of criteria, including at least one of the following:

1. ensuring that the references experiences the same environmental conditions as the data signals;

2. providing reference signals that are statistically independent;

3. providing reference signals that have nonzero kurtosis;

4. providing reference signals that are locally stationary in the statistical sense;

5. providing reference signals that have low bandwidth requirements.

27. A method for forming a virtual antenna array as set forth in

claim 14

, wherein the the nodes periodically provide updates of their relative locations and wherein after each update, a port tracking protocol is utilized to assist with blind the source separation element.