Raytheon Company

George Thomas David

Harry A Schmitt

Dennis C Braunreiter

Alphonso A Samuel

Hai-Wai Chen

A system and method for detecting a target. The inventive method includes the steps of receiving a complex return signal of an electromagnetic pulse having a real and an imaginary component; extracting from the imaginary component information representative of the phase component of the return signal; and utilizing the phase component to detect the target. Specifically, the phase components are those found from the complex range-Doppler map. More specific embodiments further include the steps of determining a power spectral density of the phase component of the return signal; performing a cross-correlation of power spectral density of the phase component of the return signal between different antenna-subarray (quadrant channels); and averaging the cross-correlated power spectral density of the low frequency components. In an alternative embodiment, the cross-correlation is performed on the phase component of the range-Doppler map directly. This signal can then be averaged to potentially provide improved detection of targets. The cross-correlations of the power spectral densities derived from the complex valued range-Doppler map are then used to detect the target in the presence of monostatic clutter. An additional teaching relates to a utilization of the phase component to ascertain a direction of the target and thereby effect target tracking as well as target detection.

System and method for detecting and estimating the direction of near-stationary targets in monostatic clutter using phase information

A radar system and radar processing method includes a number of aspects for providing improved function. The system and method may employ one or more of the following aspects: timely range-velocity (range-Doppler) compensation for target nonstationarity by integration along hypothesized range-Doppler trajectories, allowing noncoherent integration over an elongated time interval; noncoherent integration of an enlarged signal set obtained from overlapped coherent processing intervals (CPIs); hypothesized joint multiple accelerations used to generate multiple hypothesized range-Doppler trajectories; and sliding window integration to increase data output rates with use of large noncoherent integration intervals (NCIs). These aspects allow for improved signal-to-noise ratios, for acquisition and tracking of targets at longer ranges, and for improved target parameter estimation.

Noncoherent gain enhancement technique for non-stationary targets

A system and method of processing data in a sensor system which receives signal returns from pulsed coherent transmitted signals which are transmitted at a pulse repetition rate and with a pulse repetition interval (PRI). The method includes providing range-filtered data in response to the received signal returns; formatting successive sets of data received during a post detection integration (PDI) interval into a plurality of overlapping coherent processing interval (CPI) data sequences; performing FFT processing on the overlapping CPI data sequences to provide transformed data sequences; performing range-sample CPI processing on the transformed data sequences; and performing noncoherent integration (NCI) processing on output data from the range-sample CPI processed data sequences over a range trajectory in accordance with hypothesized radar-target range rate to provide noncoherent gain-enhanced output data. A range trajectory derived from a hypothesized radar-target range rate is updated at a compensation rate no more often than once per PDI interval.

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Oro Valley, AZ, United States of America

George Thomas David