Receiver and method for blind adaptive thresholding using noise estimator

1. A receiver for estimating noise power and establishing a false alarm detector threshold, comprising:

an antenna array comprising a plurality of antenna subarrays on which multiple communications signals are received over a communications channel;

at least one channelizer for splitting the communications signal into multiple frequency sub-bands per subarray, each having a channel output; and

at least one noise estimator and detector operative at said channel outputs for estimating noise power and setting a detector threshold used in detecting false alarms by forming a temporal covariance matrix on each channel output, performing an eigenvalue decomposition on the temporal covariance matrix, selecting candidate channels using the eigenvalue spread per channel, computing a noise power estimate from the candidate channels and setting a detector threshold for detecting false alarms based on the noise power estimate.

2. The receiver according to claim 1 , wherein said at least one noise estimator and detector is operative for estimating noise on a 2×2 per space-frequency-polarized channel.

3. The receiver according to claim 1 , and further comprising a Constant False Alarm Rate (CFAR) detector that detects and filters false alarms based on the detector threshold.

4. The receiver according to claim 1 , wherein one subarray is selected for estimating noise.

5. The receiver according to claim 1 , wherein each channel output includes a noise estimator and detector.

6. The receiver according to claim 1 , wherein at least one noise estimator and detector is distributed at each frequency sub-band.

7. The receiver according to claim 1 , and further comprising a plurality of processing and detection layers having at least one noise estimator and detector for scaling a noise level by bandwidth ratios.

8. The receiver according to claim 1 , wherein said at least one noise estimator and detector is operative for decomposing a correlation matrix without an eigenvalue computation using quadratic factoring results.

9. The receiver according to claim 1 , wherein at least one noise estimator and detector is operative for pooling candidate channels.

10. A receiver for estimating noise power and establishing a false alarm detector threshold, comprising:

an antenna array comprising a plurality of antenna subarrays on which multiple communications signals are received over a communications channel;

at least one channelizer for splitting the communications signal into multiple frequency sub-bands per subarray, each having a channel output; and

at least one noise estimator and detector operative at said channel outputs for estimating noise power and setting a detector threshold used for detecting false alarms by forming a temporal covariance matrix on each channel output, performing an eigenvalue decomposition on the temporal covariance matrix, selecting candidate channels using the eigenvalue spread per channel, computing a noise power estimate from the candidate channels and setting a detector threshold for detecting false alarms based on the noise power estimate, and further comprising a circuit that updates the noise estimate based on dwell data.

11. The receiver according to claim 10 , wherein said circuit for updating the noise estimate comprises a filter set to unity gain.

12. The receiver according to claim 10 , wherein said at least one noise estimator and detector is operative for estimating noise on a 2×2 per space-frequency-polarized channel.

13. The receiver according to claim 10 , and further comprising a constant false alarm rate (CFAR) detector that detects and filters false alarms based on the detector threshold.

14. The receiver according to claim 10 , wherein one subarray is selected for estimating noise.

15. The receiver according to claim 10 , wherein each channel output includes a noise estimator and detector.

16. The receiver according to claim 10 , wherein at least one noise estimator and detector is distributed at each frequency sub-band.

17. The receiver according to claim 10 , and further comprising a plurality of processing and detection layers having at least one noise estimator and detector for scaling a noise level by bandwidth ratios.

18. The receiver according to claim 10 , wherein said at least one noise estimator and detector is operative for decomposing a correlation matrix without an eigenvalue computation using quadratic factoring results.

19. The receiver according to claim 10 , wherein at least one noise estimator and detector is operative for pooling candidate channels.

20. A method for estimating noise power and establishing a threshold for communications signals received over a communications channel, comprising:

receiving multiple communications signals within an antenna array comprising a plurality of antenna subarrays;

splitting the communications signals into multiple frequency sub-bands per subarray, each having a channel output; and

estimating noise power and setting a detector threshold used in detecting false alarms by forming a temporal covariance matrix on each channel output, performing an eigenvalue decomposition on the temporal covariance matrix, selecting candidate channels using the eigenvalue spread per channel, computing a noise power estimate from the candidate channels and setting a detector threshold for detecting false alarms based on the noise power estimate.

21. The method according to claim 20 , which further comprises estimating the noise on a 2×2 per space-frequency-polarized channel.

22. The method according to claim 20 , which further comprises decomposing a correlation matrix without an eigenvalue computation using quadratic factoring results.