Influence and compensation of target motion on monopulse estimation in PD radar

Pulse Doppler (PD) radar system with monopulse estimation can effectively acquire the location information of weak target, since it combines the advantages of coherent integration and monopulse technique. However, as it takes some time to realize the coherent integration, target motion will result in the decline of integration efficiency, thus affects the angle measurement precision. This paper investigates the principle of monopulse estimation in PD radar and the influence of target motion on angle measurement. A modified expression for angle measured value is presented when target has tangential motion, which can be interpreted as the midpoint angle of target motion track. Moreover, the target radial motion can be compensated by envelope interpolation method in time domain with the prior information of velocity, or by Keystone transform method in frequency domain without velocity information. Finally, the availability of the modification and compensation is verified by simulation.