Simulation of Multi-satellite GNSS Reflected Signals and Design of Simulator

摘要

Using GNSS-R technology for remote sensing of surface parameters has become a new trend in the field of remote sensing.With the rapid development of GNSS-R technology,GNSS-R simulation has become one of the new hot spots.Now the researches of the GNSS-R simulation are all the simulations that consider a single star or a single frequency point,and in actual applications,the signal captured by the receiver is often the reflected signals of multiple stars.In view of this situation,from the perspective of multi-satellite simulation,this paper gives the model of GNSS-R multi-satellite ocean simulation on the basis of analyzing the remote sensing principle,reflection signal model and simulation principle of GNSS-R technology.Based on the GNSS-R multi-satellite ocean simulation model and the fast parallel computing capability of GPU,the GNSS-R multi-satellite ocean simulator was designed.Finally,the direct and reflected signals generated by the GNSS-R multi-satellite simulator were tested and verified.The results show that the positioning result of the direct signal meets the positioning accuracy requirements;The delay-related power results obtained from the simulated two-satellite reflected signals processing are in good agreement with the theoretical model,and the correlation coefficients are all above 0.99;The generated signals are used for GNSS-R height measurement technology,the height measurement error is about 1.4~1.8 m,which is in line with the accuracy of the C/A code ranging receiver;And the parallel operation of the GPU for multi-satellite simulation calculation is 800—900 times higher than the traditional CPU calculation.It proves that the proposed model and the designed simulator are feasible and accurate.