Research on GNSS-R model and delay-Doppler characteristics of reflected signal from sea surface

The modeling of sea surface reflected signal of GNSS is of great significance for Global Navigation Satellite System-Reflectometry (GNSS-R) remote sensing applications. Aiming at the modeling problem of GNSS reflected signal on the sea surface, the Z-V model is adopted in this paper to study the characteristics of one-dimensional time delay correlation power and two-dimensional delay-Doppler correlation power of GNSS reflected signal. The variation of one-dimensional correlation power is analyzed under different wind speeds, and the influence of time-delay interval and Doppler interval on delay-Doppler map (DDM) is also discussed in detail. Numerical results show that the correlation power of GNSS reflected signal is sensitive to sea surface wind speed, and appropriate time delay and Doppler interval parameters should be selected in DDM waveform simulation. The GNSS-R model can simulate the correlation power of GNSS reflected signal under different sea conditions, which is able to provide theoretical model support for GNSS-R reflected signal simulation and marine remote sensing applications.