Design and Validation of CPQC-NAV, A New LEO Navigation Augmentation Signal Compatible with GNSS

LEO navigation augmentation system has become an inevitable choice and development direction to meet the urgent requirements of higher precision, higher reliability and higher security PNT in emerging satellite navigation applications. Therefore, the compatibility between LEO navigation augmentation signal and GNSS signal has become a problem to be solved, the compatibility design requirements of LEO navigation augmentation signals and GNSS signals are mainly reflected in two aspects: 1. Reasonable compatibility design can make traditional GNSS receivers suitable for LEO navigation augmentation system through a small number of system upgrades, which expands the service scope of the system and improves the service quality; 2. Systematic compatibility design needs to cover on-board transceiver isolation technology, reduce the complexity of payload co frequency integration and improve system reliability. In this paper, LEO navigation augmentation compatible signal is studied from two perspectives of ground user and payload realization respectively, and the chip level pulse quasi-continuous navigation signal CPQC-NAV is optimized, which is studied in time domain, frequency domain and correlation domain. On this base, we design receiver algorithm for payload and ground user, and the performance of navigation system is theoretically analyzed. The accuracy of theoretical analysis is verified by simulation test and the feasibility of system design is verified by hardware platform. Results show that 1. the receiver of chip level pulse quasi-continuous navigation signal has good compatibility with GNSS, CPQC-NAV shows pulse characteristics in time domain and continuity in measurement domain, which has no impact on the augmentation service of LEO navigation. 2. With CPQC-NAV, the problem of the CO-frequency transceiver of the satellite payload has been effectively solved.