Abstract: Iterative methods for direction of arrival estimation of a signal at a receiver with a plurality of spatially separated sensor elements are described. A quantized estimate of the angle of arrival is obtained from a compressive sensing solution of a set of equations. The estimate is refined in a subsequent iteration by a computed error based a quantized estimate of the direction of arrival in relation to quantization points offset from the quantization points for the first quantized estimate of the angle of arrival. The iterations converge on an estimated direction of arrival.

Abstract: Iterative methods for direction of arrival estimation of a signal at a receiver with a plurality of spatially separated sensor elements are described. A quantized estimate of the angle of arrival is obtained from a compressive sensing solution of a set of equations. The estimate is refined in a subsequent iteration by a computed error based a quantized estimate of the direction of arrival in relation to quantization points offset from the quantization points for the first quantized estimate of the angle of arrival. The iterations converge on an estimated direction of arrival.

Abstract: Iterative methods for direction of arrival estimation of a signal at a receiver with a plurality of spatially separated sensor elements are described. A quantized estimate of the angle of arrival is obtained from a compressive sensing solution of a set of equations. The estimate is refined in a subsequent iteration by a computed error based a quantized estimate of the direction of arrival in relation to quantization points offset from the quantization points for the first quantized estimate of the angle of arrival. The iterations converge on an estimated direction of arrival.

Abstract: Iterative methods for direction of arrival estimation of a signal at a receiver with a plurality of spatially separated sensor elements are described. A quantized estimate of the angle of arrival is obtained from a compressive sensing solution of a set of equations. The estimate is refined in a subsequent iteration by a computed error based a quantized estimate of the direction of arrival in relation to quantization points offset from the quantization points for the first quantized estimate of the angle of arrival. The iterations converge on an estimated direction of arrival.

Abstract: A method for estimating the frequency of a single frequency complex exponential tone in additive Gaussian noise, comprising the steps of: performing the fast Fourier transform (FFT) on the tone; estimating the frequency as the frequency corresponding to the largest FFT output coefficient magnitude; computing a discriminant which is proportional to the frequency error in the initial frequency estimate using modified coefficients of the discrete Fourier transform (DFT) with center frequencies plus one half and minus one half of the FFT bin spacing relative to the initial frequency estimate; mapping the value of the discriminant into the estimate of the frequency error in the initial frequency estimate using a mathematically derived function; adding the estimate of the frequency error to the initial frequency estimate to get a first interpolated frequency estimate; computing a further discriminant which is proportional to the frequency error in the first interpolated frequency estimate using modified coefficient

Abstract: A multiple data rate detector which examines the power spectral density of the received signal and thereby determines whether the signal is wihtin one of N known data rate ranges. The invention includes a first filter, with a first passband and a second filter having a second distinct passband. First and second power detectors are provided for detecting the power associated with the output of the first and second filters. The outputs of the power detectors are compared to yield a signal indicative of the data rate.

Abstract: A coherent multiple beam antenna switching system is disclosed. The invention is adapted for use with an antenna having a switch for directing a signal through a first feed via a first channel into a output port and for directing a signal received by a second feed into said first channel at a time T. The invention includes a power detection circuit for measuring the power in the signal in the first channel via the first feed and a controller responsive to the measured power for activating the switch prior to time T to direct the signal via the second feed and a second channel to the output port. The controller includes the capability of predicting the switching of feeds and switches in the second channel in anticipation thereof. Phase detection and correction circuits are provided for aligning the signal in the second channel with the signal in the first channel. When the signals are aligned, the channels are switched at baseband to provide for coherent switching with minimal switching transients.