Communications – electrical: acoustic wave systems and devices – Echo systems – Distance or direction finding
Patent
1992-07-17
1994-08-16
Pihulic, Daniel T.
Communications, electrical: acoustic wave systems and devices
Echo systems
Distance or direction finding
367905, 342379, G01S 1500
Patent
active
053392841
ABSTRACT:
A signal processor eliminates sidelobe response from signals produced by a spaced antenna array that forms a single beam using spatial frequencies. The signal processor also produces error signals. The signal processor uses a phase coherent local oscillator to simultaneously convert the wavefront signal from each element of the antenna array to three different first intermediate frequency signals IF. The first IF signals of each element are cross-correlated with the first IF signals from each of the other array elements to form the signals containing sampled spatial frequency components IF.sub.2. Cross-correlating a second time using the sampled spatial frequencies as inputs produces signals containing derived spatial frequency components IF.sub.3. The signals containing derived spatial frequency components are synchronously detected (phase compared) and summed to provide a single beam output signal. The summed output signal passes through a linear peak detector biased to the peak of the largest even sidelobe such that only signals within the main beam and above the bias level appear in the final output. The derived spatial frequencies are also phase shifted by 90.degree. and detected signals containing "imaginary" spatial frequency components. The sum of the signals with imaginary components represents an error pattern. Also, summation of the signals with imaginary components for the odd order spatial frequency harmonics produces an error signal approximating a signum function of the angle of incidence of the incoming wavefront.
REFERENCES:
patent: 3042916 (1962-07-01), Clarke
patent: 3268890 (1966-08-01), Birge
patent: 4173759 (1979-11-01), Bakhru
patent: 4213131 (1980-07-01), Kaiser, Jr.
patent: 4495502 (1985-01-01), Masak
patent: 4498083 (1985-02-01), Gutleber
patent: 4500883 (1985-02-01), Gutleber
patent: 4525716 (1985-06-01), Carlin
patent: 4577193 (1986-03-01), Kiuchi et al.
patent: 4717919 (1988-01-01), Cherrette et al.
patent: 4720712 (1988-01-01), Brookner et al.
patent: 4734701 (1988-03-01), Grobert
Brookner, Radar Technology, .COPYRGT.1977 Artech House, Inc., Ch. 21, pp. 289-335.
Kaiser, J., "Single beam synthesis from thinned arrays," J. Acoust. Soc. Am., vol. 76(2), Aug. 1984, pp. 465-474.
Frederick Herold & Associates, Inc.
Pihulic Daniel T.
LandOfFree
Signal processor for elimination of sidelobe responses and gener does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Signal processor for elimination of sidelobe responses and gener, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Signal processor for elimination of sidelobe responses and gener will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-958254