Direct Digital Synthesis Applied in GNSS Signal Simulation
Jian Li · Radio Engineering of China · 2009
After analyzing the popular methods of frequency synthesis and the requirements of GNSS signal simulation,the method of direct digital synthesis (DDS) is applied to generate the satellite signal.The design parameters of DDS are determined according to the specific synthesis requirements.Based on the mathematic model of single-channel GNSS signal synthesis,the architecture of synthesizing unit of individual satellite is designed.By quantitatively analyzing the errors of synthesizing brought by quantization in the processing of the control parameters,a viable compensating method is provided.Finally,the problems in applying DDS for GNSS signal simulation are solved.