Beam former using phase difference enhancement

1. A beamformer for use with a plurality of sensors each configured to generate a sensor input signal representable by an input vector having phase and magnitude components, the beamformer comprising:

a phase difference enhancement circuit configured to enhance a phase difference between at least two sensor input signals as a function of a phase difference of input vectors corresponding to at least two sensor input signals and to thereby generate one or more phase-enhanced signals;

a first circuit configured to generate a first circuit output signal form at least two first circuit input signals;

a second circuit configured to generate a second circuit output signal from at least two second circuit input signals;

an adaptive filter configured to receive the second circuit output signal and generate a filtered signal therefrom; and

a third circuit configured to receive the filtered signal and a delayed version of the first circuit output signal and generate a difference signal therefrom,

wherein at least one phase-enhanced signal is applied as one of the input signals to at least one of the first and second circuits.

2. The device of claim 1 wherein the sensors are arranged in a broadside array.

3. The device of claim 1 wherein the phase difference enhancement circuit is configured to effect signal phase compression.

4. The device of claim 1 wherein the phase difference enhancement circuit is configured to effect signal phase expansion.

5. The beamformer of claim 1 wherein a phase-enhanced signal is applied as the input signal to the first circuit.

6. The beamformer of claim 1 wherein a phase-enhanced signal is applied as the input signal to the second circuit.

7. The beamformer of claim 1 wherein at least one phase-enhanced signal is applied as the input signal to the first circuit and at least one phase-enhanced signal is applied as the input signal to the second circuit.

8. The beamformer of claim 1 wherein the second circuit is a differencing circuit of a blocking matrix of a generalized side-lobe canceler (GSC).

9. The beamformer of claim 1 wherein the adaptive filter is a finite impulse response (FIR) filter.

10. The beamformer of claim 9 , wherein the adaptive filter has filter coefficients that are a function of the difference signal.

11. The beamformer of claim 1 , wherein the adaptive filter has filter coefficients that are a function of the difference signal.

12. The beamformer of claim 1 wherein the sensors are arranged in an end-fire array.

13. A noise reduction method for use with a plurality of sensors each configured to generate a sensor input signal representable by an input vector having phase and magnitude components, the method comprising:

enhancing a phase difference between at least two sensor input signals as a function of a phase difference of input vectors corresponding to at least two sensor input signals to thereby generate one or more phase-enhanced signals;

generating a first circuit output signal from at least two first circuit input signals;

generating a second circuit output signal from at least two second circuit input signals;

adaptively filtering the second circuit output signal to thereby generate a filtered signal therefrom; and

generating a difference signal between the filtered signal and a delayed version of the first circuit output signal,

wherein at least one phase-enhanced signal is applied as one of the input signals to at least one of the first and second circuits.

14. The method of claim 13 , wherein the sensors are arranged in a broadside array.

15. The method of claim 13 , wherein the sensors are arranged in a end-fire array.

16. The method of claim 13 , wherein enhancing a phase difference between at least two sensor input signals comprises effecting signal phase compression.

17. The method of claim 13 , wherein enhancing a phase difference between at least two sensor input signals comprises effecting signal phase expansion.

18. The method of claim 13 , wherein a phase-enhanced signal is applied as the input signal to the first circuit.

19. The method of claim 13 , wherein a phase-enhanced signal is applied as the input signal to the second circuit.

20. The method of claim 13 , wherein at least one phase-enhanced signal is applied as the input signal to the first circuit and at least one phase-enhanced signal is applied as the input signal to the second circuit.

21. The method of claim 13 , wherein the second circuit output signal is a difference signal of a blocking matrix of a generalized side-lobe canceler (GSC).

22. The method of claim 13 , wherein adaptively filtering comprises using a finite impulse response (FIR) filter.

23. The method of claim 22 , wherein the FIR filter has filter coefficients that are a function of the difference signal.

24. The method of claim 13 , wherein the adaptive filter has filter coefficients that are a function of the difference signal.

25. An adaptive beamformer for use with at least two sensors each producing a sensor input signal representable by an input vector having phase and magnitude components, the adaptive beamformer including:

a phase difference enhancement circuit for enhancing a phase difference of at least two sensor input signals, the phase difference enhancement circuit generating at least two phase-enhanced signals having a phase difference that is a function of the phase difference between at least two input vectors.

26. The adaptive beamformer of claim 25 , wherein at least one of said sensors is an array system comprising a plurality of sensor elements and a combining circuit, each of said sensor elements producing a sensor element signal, with said sensor element signals being combined to produce the sensor input signal corresponding to said one of said sensors.

27. The adaptive beamformer of claim 25 , wherein the at least two sensor input signals comprise processed representations of sensor input signals.