Joint acquisition strategy of GNSS satellites for computational cost reduction

This paper proposes a joint acquisition strategy of Global Navigation Satellite Systems (GNSS) satellites to reduce the number of correlations required in the acquisition process. The proposed method generates a local satellite signal replica, which contains the sum of two or more satellite codes, and performs a grid search with this augmented local replica. The grid is then analyzed with a test statistic function, resulting in a delay/Doppler grid with as many maxima as satellites present in the local replica. Then, maxima are identified using an extra correlation per possible satellite. The computational reduction benefits and the associated performance have been identified. Closed form expressions for both the detection and the false alarm probabilities have been found and validated by Monte Carlo simulations for GPS L1 C/A and Galileo E1 signals. An implementation scheme is also presented.