Influence of frequency synchronization errors on hybrid bistatic SAR system

The influences of frequency synchronization errors on the spaceborne/airborne hybrid bistatic SAR is uniquely studied. The analysis is based on the results in airborne bistatic SAR systems, distributed spaceborne SAR systems, interferometric SAR systems and an existing error model in a published literature. Theoretical analysis is carried out using the typical parameters of hybrid bistatic SAR systems and several simulations were performed to validate the theoretical result. It shows that if the frequency accuracy of the frequency source is superior to the level of 10^-8~10^-9 no compensation scheme is needed. It is a pity that the above requirement may not be satisfied when the frequency source has run a sufficiently long time without calibration. Therefore in practical projects some synchronization measures must be taken and the residual frequency synchronization error is restricted to 10 KHz.