Abstract: A method and apparatus for calibrating range in a radar system. Due mainly to temperature changes in a radar system which cause frequency deviation error, range errors can be introduced into the radar system, thus adversely affecting the determination of the position of targets relative to the host platform. These range errors can be corrected by detecting and accurately estimating the frequency deviation error of a radar system. The present invention improves target position determination performance in a radar system by reducing errors introduced by the frequency deviation error. The present invention relies upon the observation that the Doppler range rate is largely unaffected by frequency deviation error, and thus, is approximately equal to the actual range rate. In accordance with a first range calibration technique of the present invention, the radar system measures the range, Doppler range rate, and azimuth angle of a target during at least two successive time instances.

Abstract: A method and apparatus for calibrating range in a radar system. Due mainly to temperature changes in a radar system which cause frequency deviation error, range errors can be introduced into the radar system, thus adversely affecting the determination of the position of targets relative to the host platform. These range errors can be corrected by detecting and accurately estimating the frequency deviation error of a radar system. The present invention improves target position determination performance in a radar system by reducing errors introduced by the frequency deviation error. The present invention relies upon the observation that the Doppler range rate is largely unaffected by frequency deviation error, and thus, is approximately equal to the actual range rate. In accordance with a first range calibration technique of the present invention, the radar system measures the range, Doppler range rate, and azimuth angle of a target during at least two successive time instances.

Abstract: A method and apparatus for calibrating azimuth boresight in a radar system. Antenna boresight misalignment can cause radar systems to inaccurately determine the position of targets relative to a platform vehicle. These errors can be corrected by detecting and accurately measuring a boresight offset angle defined as the angle between the radar antenna boresight and the direction of travel of the host platform vehicle. Several antenna boresight calibration techniques are described. A first technique calculates the boresight offset angle by obtaining target range and azimuth angle measurements at two instants in time. The boresight offset angle is determined by the geometric relationship of the offset angle, target range and azimuth values obtained at two successive time instants. A refined approach obtains target range and azimuth values at several successive time instants, calculating interim boresight offset angles at each time instant.