Design methodology and performance analysis for a novel constant envelope modulation signal of GNSS

With the growing demand for GNSS application, the satellite navigation payload may supply several signal components and modulation types in each frequency. This trend will continue for the future GPS/Galileo/Compass system. In order to provide a precision positioning service, the satellite navigation payload must supply a continuous, precise and high integrity signal. The signal quality is determined by the linear distortion and the non-linear distortion in the payload system. The non-linear distortion can be decreased by the constant envelope signal modulation. This paper will study the arithmetic of Coherent Adaptive Subcarrier Modulation (CASM) for 4-signal case and the modeling algorithm of pre-post filter/high power amplifier (HPA). At last, the ideal receiver will give the precision of ranging.