Abstract: A method of generating an image of a volume ahead of an aerial vehicle is provided. The method comprises determining a position of the aerial vehicle and generating a terrain image corresponding to ground features correlated to the position of the aerial vehicle. Obstacle data pertaining to a set of obstacles ahead of the aerial vehicle is determined with a forward looking sensor. An obstacle overlay image is generated and overlain onto the terrain image to generate a composite image.

Abstract: Systems and methods for Doppler beam sharpening in a radar altimeter are provided. In one embodiment, a method comprises receiving a return signal at a radar altimeter receiver and applying a first gate to the return signal to select at least a first component of the return signal. Spectral analysis is performed on the first component of the return signal to generate a plurality of frequency bins, wherein each frequency bin is centered around a different frequency across a Doppler shift frequency spectrum for the first component of the return signal. The method further comprises tracking the first component of the return signal, selecting a first frequency bin of the plurality of frequency bins based on the Doppler shift frequency of the first component of the return signal, and outputting a portion of the first component of the return signal falling within the first frequency bin for further processing.

Abstract: Systems and methods for Doppler beam sharpening in a radar altimeter are provided. In one embodiment, a method comprises receiving a return signal at a radar altimeter receiver and applying a first gate to the return signal to select at least a first component of the return signal. Spectral analysis is performed on the first component of the return signal to generate a plurality of frequency bins, wherein each frequency bin is centered around a different frequency across a Doppler shift frequency spectrum for the first component of the return signal. The method further comprises tracking the first component of the return signal, selecting a first frequency bin of the plurality of frequency bins based on the Doppler shift frequency of the first component of the return signal, and outputting a portion of the first component of the return signal falling within the first frequency bin for further processing.

Abstract: A method of generating an image of a volume ahead of an aerial vehicle is provided. The method comprises determining a position of the aerial vehicle and generating a terrain image corresponding to ground features correlated to the position of the aerial vehicle. Obstacle data pertaining to a set of obstacles ahead of the aerial vehicle is determined with a forward looking sensor. An obstacle overlay image is generated and overlain onto the terrain image to generate a composite image.

Abstract: A radar altimeter for vehicles that operate with a load suspended underneath is described. The radar altimeter includes a transmitter configured to transmit radar signals toward the ground, a receiver configured to receive reflected radar signals from the ground and from the suspended load, and at least one altitude processing channel configured to receive signals from the receiver. The radar altimeter also includes a load profile channel configured to receive signals from the receiver. The load profile channel limits an altitude processing sensitivity of the radar altimeter between the radar altimeter and the suspended load to reduce a likelihood that the radar altimeter will process signals reflected by the suspended load.

Abstract: A method for calculating a center frequency and a bandwidth for a radar doppler filter is herein described. The center frequency and bandwidth are calculated to provide radar performance over varying terrain and aircraft altitude, pitch, and roll. The method includes receiving an antenna mounting angle, a slant range, and velocity vectors in body coordinates, calculating a range swath doppler velocity, a track and phase swath bandwidth, and a phase swath doppler velocity. The method continues by calculating a range swath center frequency based on the range swath doppler velocity, calculating a phase swath center frequency based on the phase swath doppler velocity, and calculating a level and verify swath bandwidth based upon the track and phase swath bandwidth.

Abstract: A method for calculating a center frequency and a bandwidth for a radar doppler filter is herein described. The center frequency and bandwidth are calculated to provide radar performance over varying terrain and aircraft altitude, pitch, and roll. The method includes receiving an antenna mounting angle, a slant range, and velocity vectors in body coordinates, calculating a range swath doppler velocity, a track and phase swath bandwidth, and a phase swath doppler velocity. The method continues by calculating a range swath center frequency based on the range swath doppler velocity, calculating a phase swath center frequency based on the phase swath doppler velocity, and calculating a level and verify swath bandwidth based upon the track and phase swath bandwidth.

Abstract: A method for reducing effects of terrain return fading due to summation of out of phase radar returns in determining locations of radar targets is described. The method comprises determining an interferometric angle, &PHgr;, to a radar target based on at least one radar return and filtering the interferometric angle, &PHgr;, by adjusting an effect of terrain features contributing to the interferometric angle, &PHgr;, proportionally to a degree of radar return fading resulting from the terrain features of the radar targets. A corrected interferometric angle, &PHgr;out., is then provided, based at least in part on the filtering.

Abstract: A method for calculating a center frequency and a bandwidth for a radar doppler filter is herein described. The center frequency and bandwidth are calculated to provide radar performance over varying terrain and aircraft altitude, pitch, and roll. The method includes receiving an antenna mounting angle, a slant range, and velocity vectors in body coordinates, calculating a range swath doppler velocity, a track and phase swath bandwidth, and a phase swath doppler velocity. The method continues by calculating a range swath center frequency based on the range swath doppler velocity, calculating a phase swath center frequency based on the phase swath doppler velocity, and calculating a level and verify swath bandwidth based upon the track and phase swath bandwidth.