Design on return signal simulator of scatterometer and method of generating its signal

The return signal simulator (RSS) of the Chinese spaceborne scatterometer is designed in order to compensate for the insufficiency of the common test and calibration device. The RSS can calibrate and test conveniently the transfer function and signal processing function of the scatterometer in ground-based tests. It employs the principle of pulse reconstruction. The characteristics of the return signal are generated by a digital method. The accurate round trip path delay of the radio-frequency signal, pulse width modulation and Doppler frequency shift are simulated. Also the phase difference shift is improved. By using the RSS, the testing and calibrating experiments for the scatterometer are implemented, which indicate that the generated return signal not only can fully express the statistics of the real return signal, but also can meet the requirements of testing and calibrating the scatterometer. This method of generated return signal can be realized easily and the results are correct, so it will provide a reference for future RSSs.