Research On Realization Technology Of Deep Space Channel Simulator

During the initial phase of deep space explorations, a reliable communication link between a deep space satellite and the Earth will be required. The deep space telecommunication is subjected to be affected by the effects of the long distance, strong noise, the high Doppler shift and complicate space environment, etc. Signals from deep space probes are usually very weak and complicated, so an advanced receivers to keep a reliable communication link is very importmant. The Deep Space Channel Simulator (DSCS) can be used to evaluate the performance of deep space communication equipments. In this paper, a Deep Space Channel Simulator which is"universal, multi-modulation, arbitrary-data rate and orbit-information- based"is designed and implemented with both virtual instrument and FPGA.First of all, based on the characteristics of deep space, a model which includs White Gaussian noise, signal loss and Doppler shift is proposed. Some common modulate methods are studied and simulated and finally four methods are chosen to be adoptted in the DSCS. Secondly, based on the requerments of DSCS and the features of both virtual instrument and FPGA, two design plans are proposed separately. As the requerment of"universal", the function models of software are recoupled to improve its reusability and its customizablity.Thirdly, key techniques such as DDS and implementation of White Gaussian noise on FPGA are researched.At last, the DSCS based on virtual instrument and FPGA are implemented and their performance is tested. By comparing the output signal with theoretical value, the veracity and validity of the simulator is confirmed.