Dual binary phase-shift keying tracking method for Galileo E5 AltBOC(15,10) signal and its thermal noise performance

Coherent wideband processing for the Galileo E5 AltBOC signal encounters a great challenge because of its modulation complexity, multi-peaked auto correlation function (ACF) and large bandwidth. In this study, a new tracking method called `dual binary phase-shift keying (BPSK) tracking´ (DBT), which is derived from its reception models and double estimator technique (DET) methodology, is specially designed for the Galileo E5 signal. While this method can achieve the full potential of the Galileo E5 signal in ranging performance, it features a robust wideband processing technique, backward compatibility with conventional BPSK signal tracking, and easy implementation in hardware. More specifically, the DBT method makes use of the coherence of the lower and upper bands of the Galileo E5 signal and decouples sub-carrier phase and carrier phase through coherently combining correlator outputs of the two bands, and then implements independent tracking for code, sub-carrier and carrier based on the DET methodology. Furthermore, thermal noise performances of this new method are given and verified by processing both simulated and real Galileo E5 signals.