Simultaneous nulling and beamfocusing from disparate antennas

• US 10,277,295 B2
• Filed: 01/29/2014
• Issued: 04/30/2019
• Est. Priority Date: 01/29/2014
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Wittenberg, Peter S., Michal, Debra P.
• Primary Examiner(s): Ahn, Sung S
• Application Number:
  US14/167,265
• Publication Number:
  US 20150215021A1
• Time in Patent Office: 1,917 Days
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0634 Antenna weights or vector/matrix coefficients
• CPC Class Codes: H04B 7/086 using weights depending on external parameters, e.g. direction of arrival [DOA], predetermined weights or beamforming

Abstract

In an antenna array, signals may be manipulated to increase coherency at certain locations (beamfocusing) and reduce or cancel the signals at other locations (nulling). This is accomplished by multiplying the signals received or transmitted by the set of antennas by a weight vector that is generated by determining a covariance matrix based on a vector representing signals at the set of antennas, vectors representing the desired beamfocusing and nulling locations, and a desired nulling depth.

Claims

1. A method of beamfocusing and nulling signals carried by electromagnetic waves, the method comprising:

determining a first vector x representing a magnitude and phase of signals transmitted or received at each of a plurality of disparate antennas, wherein each of the plurality of disparate antennas is configured with electromagnetic transmission and reception components and a signal processing component, and wherein each disparate antenna is geographically separate from each other disparate antenna;

determining a covariance matrix of the first vector x (R_xx) based on the received signals as a product of the first vector x and a Hermitian transpose of the first vector x^H;

determining a complex vector b defining a magnitude and phase of signals that would be received by the plurality of disparate antennas from a location b where beamforming is desired;

determining a complex vector n defining a magnitude and phase of signals a transmitted by the plurality of disparate antennas that would produce a null at desired location n;

determining a weight vector w according to

2. A system for beamfocusing and nulling signals carried by electromagnetic waves, the system comprising:

a plurality of disparate antennas configured with electromagnetic transmission and reception components and a signal processing component, wherein each disparate antenna is geographically separate from each other disparate antenna;

a memory comprising executable instructions; and

a processor operatively coupled to the plurality of disparate antennas, wherein the processor, when executing the executable instructions, effectuates operations comprising;

determining a first vector x representing a magnitude and phase of signals received at each of a plurality of disparate antennas;

determining a covariance matrix of the first vector x (R_xx) based on the received signals as a product of the first vector x and a Hermitian transpose of the first vector x^H;

determining a complex vector b defining a magnitude and phase of signals that would be received by the plurality of disparate antennas from a location b where beamforming is desired;

determining a complex vector n defining a magnitude and phase of signals a transmitted by the plurality of disparate antennas that would produce a null at desired location n;

determining a weight vector w according to

3. A non-transitory computer-readable storage device having computer-readable instructions stored thereon, the computer-readable instructions comprising instructions that, when executed by a processor, cause the processor to effectuate operations comprising:

determining a first vector x representing a magnitude and phase of signals transmitted or received at each of a plurality of disparate antennas, wherein each of the plurality of antennas is configured with electromagnetic transmission and reception components and a signal processing component, and wherein each disparate antenna is geographically separate from each other antenna;

determining a covariance matrix of the first vector x (R_xx) based on the received signals as a product of the first vector x and a Hermitian transpose of the first vector x^H;

determining a complex vector b defining a magnitude and phase of signals that would be received by the plurality of disparate antennas from a location b where beamforming is desired;

determining a complex vector n defining a magnitude and phase of signals a transmitted by the plurality of disparate antennas that would produce a null at desired location n;

determining a weight vector w according to

4. A method of beamfocusing and nulling signals carried by electromagnetic waves, the method comprising:

determining a first vector representing signals received at each of a plurality of disparate antennas, wherein each of the plurality of disparate antennas is configured with electromagnetic transmission and reception components and a signal processing component, and wherein each disparate antenna is geographically separate from each other disparate antenna;

determining a weight vector based on the first vector, a nulling location, and a beamfocusing location; and

applying the weight vector to signals at the plurality of disparate antennas, wherein applying the weight vector to the signals at the plurality of disparate antennas comprises multiplying signals transmitted or received by the plurality of antennas by the weight vector, thereby achieving beamfocusing at the beamfocusing location and nulling at the nulling location;

wherein determining the weight vector comprises generating a covariance matrix using a beamfocusing vector representing a magnitude and a phase of signals received at the beamfocusing location, and a nulling vector representing a magnitude and a phase of signals received at the nulling location; and

wherein said plurality of disparate antennas comprises at least one antenna carried by a mobile vehicle separate from the other disparate antenna(s)

wherein at least one of said plurality of disparate antennas is of a first antenna type including an omnidirectional type, a dipole type and an array type, and another of the said plurality of disparate antennas is of a second antenna type different than the first antenna type.