Research And Realization Of Satellite Navigation Communication Integrated Signal

With the gradual improvement of GNSS and the rapid development of satellite communications,SNCI research has gradually become an important topic in recent years.The combination of CCSK and GNSS signals is a new idea to realize SNCI signals.The scheme has good backward compatibility in both signal and equipment,and has a good promotion prospect.In this essay,the hardware implementation of the signal system is studied,and the generation and detection algorithm of the signal and its hardware design architecture are proposed,and the feasibility of the signal is verified.Firstly,this essay introduces the design principle of increasing the GNSS signal rate by adding a CCSK communication signal with the same frequency,synchronization,same power,and same code family as the GNSS signal.The traditional GNSS signal is used as a pilot channel to provide synchronization and transmit navigation information,and the communication channel uses CCSK technology to transmit data information.According to the characteristics of SNCI signal,this essay designs a generation algorithm and performs hardware verification based on FPGA platform.Secondly,the detection algorithm of SNCI signal is designed in this essay,and its hardware implementation is introduced in detail.Aiming at the difficulty of synchronization of CCSK communication signals,a synchronization method of controlling the local code of the communication channel through the pilot channel is designed.Each functional module of the receiver pilot branch and the communication branch has strong versatility,which proves that the signal receiver has strong compatibility.It is confirmed by hardware testing that the SNCI signal transmission system implemented in this essay can transmit information correctly,and can also achieve reliable signal transmission in the noise environment of-18 d B～-16 d B.Finally,this essay implements hardware verification for two improved signals based on SNCI signals.One is the OCSS signal system that enhances the peak-to-peak value of the correlation.This method changes the cross-correlation between the pilot channel and the communication channel from an interference factor to an enhancement factor,which improves the anti-noise performance of the SNCI signal system.The hardware experiment proves that the OCSS signal system can perform reliable signal transmission in the noise environment of-20 d B～-16 d B.The other is the CDIPPM signal.This technology further improves the information transmission rate,but has poor noise immunity.After hardware verification,the CDIPPM signal is not suitable as a SNCI signal,but it can be used as the extension of this study and applied in fields such as near field communication.