Yang Haiguang

Vehicleborne bistatic synthetic aperture radar imaging

A complete vehicleborne Bistatic Synthetic Aperture Radar (SAR) imaging experiment is presented in this paper. Some new technologies were used to solve synchronization problems. An algorithm named the Glide Window Echo CFAR was used to realize time synchronization and collect the echo. High stable local oscillator was employed to achieve frequency and phase synchronization, and the PRF was adjusted adaptively in the Data Acquisition Device in the receive station. Finally, the Range-Doppler algorithm with range migration correction was using to image the certain scene successfully.

A new Bi-SAR T/R relative speed estimation method using nadir echo

In this paper, a new bistatic SAR T/R relative speed estimation method using nadir echo is present. This method first exact the nadir echo from the range compressed SAR data, then the time-frequency estimation method is adopted to obtain the instantaneous frequency of the nadir echo, which is proportional to the relative speed of the T/R platform, finally, the relative speed is estimated by searching the maximum values of the STFT spectrogram at different time. Compare to the traditional motion parameter estimation method, this method can obtain the instantaneous relative speed between the T/R platforms rather than an average speed between them, and improve the quality of bistatic SAR image finally.

An imaging method and the correction of distortion for Spaceborne-airborne bistatic SAR

Because of the great speed difference between the transmitter and the receiver of the spaceborne/airborne bistatic SAR (SA-BiSAR), the bistatic angle changes with time, which makes the geometric structure of the SAR system no longer invariant, and the imaging result distort seriously and dissimilarly. In order to solve this problem the geometric model of the SA-BiSAR is established in this paper at first. Then based on the analysis to cause the image distortion, a correction method for bistatic SAR distortion named Inverse-Projection is brought up. The simulation results demonstrate that this method can work well for spaceborne/airborne configuration.