Abstract: An apparatus and method for detecting the polarization signature of radar signals reflected from a target immersed in clutter. The signal to be transmitted is split into individual horizontal, vertical, and 45.degree. polarized signals that are individually frequency shifted, and transmitted simultaneously. The reflected signals are processed in individual horizontal, vertical and 45.degree. channels so as to derive Stokes vectors corresponding to each polarization and describing the scattered field associated with that polarization. The signals representing the Stokes vectors are applied to a matrix computer which provides signals representative of a Mueller matrix which describes how the transmitted signal was transformed by the target and thus constitutes the polarization signature of that target.

Abstract: An apparatus for control of ground clutter breakthrough in MTI radar which remove hard limited clutter signals while allowing increased detection sensitivity to moving targets when such strong clutter returns are not present. Logic is provided to prevent the removal of strong moving target return even in the presence of hard limited clutter.

Abstract: An apparatus and method for detecting the polarization of signals reflected from targets immersed in clutter. Signals reflected from targets illuminated with quasimonochromatic electromagnetic signals such as FMCW radar are received by antennas responsive to orthogonally polarized components of the reflected signals. These received orthogonal signal components are then modified such that one component is phase shifted with respect to the other signal components, and the amplitudes of the signal components are varied according to predetermined angles of polarization. The resulting signals are further analyzed in a processor which detects the polarization of the reflected signals by estimating the Stokes parameters for the reflected signal. The Stokes parameters may then be used to generate detection criteria that are compared to a predetermined threshold level.

Abstract: An apparatus and method for detecting the polarization of signals reflected from targets immersed in clutter. Signals reflected from targets illuminated with quasimonochromatic electromagnetic signals such as FMCW radar are received by antennas responsive to orthogonally polarized components of the reflected signals. These received orthogonal signal components are then analyzed in a processor which detects the polarization of the reflected signal by estimating the Stokes parameters for the reflected signal. The estimated Stokes parameters may then be used to generate detection criteria that are compared to a predetermined threshold level. The presence of the target is indicated when the detection criteria level exceeds the level of the predetermined threshold.

Abstract: A detection system wherein the signal levels of a plurality of resolution cells on either side of the resolution cell of interest are compared to the signal level therein. Runs of resolution cells with signal levels that exceed or do not exceed the signal level of the resolution cell of interest are taken and a run count is determined which is utilized to establish a signal detection.