New L5/E5a Acquisition Algorithms: Analysis and Comparison

To respond to the ever-increasing demand for high accuracy position and location services, the new ranging signals broadcast by the modern and modernized Global Navigation Satellite Systems (GNSSs) exhibit significant structural innovations. New spreading sequences, data/pilot structures and tiered codes obtained by cascading secondary and primary codes are just a few examples of the innovations introduced to improve measurement accuracy, tracking robustness and tracking sensitivity. However, to fulfill the aforementioned expectations and effectively provide superior navigation solution, new receiver architectures are required. To this end, this paper presents and compares different algorithms, namely non-coherent, semi- coherent, differentially coherent and coherent combining, for the joint acquisition of the data and pilot components of the new composite GNSS signals. Each strategy is detailed from a statistical point of view and a new methodology for the characterization of the false alarm probability for coherent combing is proposed. Theoretical results are supported by Monte Carlo simulations and real data analysis.