PN Ranging Based on Noncommensurate Sampling: Zero-Bias Mitigation Methods

This paper proposes two methods to mitigate the zero bias of noncommensurate sampling based code-tracking loops to significantly improve the pseudonoise ranging accuracy. For the compensation-based method, a set of algorithms is developed to directly calculate the zero bias which is then removed from the range measurement. For the compensation-free method, a special category of sampling ratios are selected such that the zero bias is self-cancelled. Simulations validate the effectiveness of the proposed methods.