Phase Error Compensation Technique for Improved Synthetic Aperture Radar Performance

adar data contain phase errors whose sources include uncompensated platform motion and transmitter and receiver phase errors. Achieving theoretical resolution from a pulse compression system requires a method to minimize those phase errors. This article discusses a method of estimating and correcting phase errors in synthetic aperture radar data. The method requires that one or more stationary point targets be included in the data. The phase history of each reference target is estimated for the period in which the target is in the view of the radar. The phase error, computed as the deviation from the theoretical phase function, is estimated and removed from the raw data. Unfortunately, conventional continuous phase measurement requires high signal-to-noise ratio. To increase the effective signal-to-noise ratio of the raw reference target data, the targets are extracted after matched filtering, and the resulting data are inverse matched filtered. In one test data set, this phase correction method improved the synthetic aperture radar image resolution by 50%. (