Non-Coherent Unambiguous Tracking Method for Composite Binary Offset Carrier Modulated Signals Based on S-Curve Shaping Technique

We propose a noncoherent unambiguous tracking method for composite binary offset carrier modulated signals, which are used in the Galileo E1 band. The proposed method employs two linearly-combined codes to replace the commonly used multi-correlator structure. The S-curve shaping technique is proposed to generate an asymmetrical S-curve without any false lock points based on least square solutions of linear equations. A tracking loop based on the proposed method, which can be easily implemented at the hardware receivers, is provided. Simulation results reveal that the proposed method exhibits outstanding multipath mitigation performance while maintaining the operating range of the S-curve in the positive delay.