Analysis of coherent combining for GPS L1C acquisition
Date of Original Version
The GPS L1C signal is similar to other modern GNSS signals in that it has a pilot component and a data component. However, a unique aspect of this signal is an unequal power split between these two components which are transmitted in phase. Channel combining techniques to acquire modern GNSS signals using both components have previously been proposed. In this paper, the single trial detection and false alarm probabilities for GPS L1C acquisition using coherent channel combining over a single spreading code period are analytically derived taking into account the unique aspects of this signal. The optimal detector for GPS L1C acquisition in additive white Gaussian noise is also derived. A coherent combining technique with unequal power compensation is proposed for dual-component GNSS signals, such as GPS L1C, that have an unequal power split. Simulation results are used to verify the analytical results and to compare the performance of the optimal detector with coherent channel combining as well as noncoherent channel combining. It is shown that coherent channel combining with unequal power compensation outperforms the other detectors and nearly approaches the performance of the optimal detector.
25th International Technical Meeting of the Satellite Division of the Institute of Navigation 2012, ION GNSS 2012
Seals, Kelly C., William R. Michalson, Peter F. Swaszek, and Richard J. Hartnett. "Analysis of coherent combining for GPS L1C acquisition." 25th International Technical Meeting of the Satellite Division of the Institute of Navigation 2012, ION GNSS 2012 1, (2012): 384-393. https://digitalcommons.uri.edu/ele_facpubs/1050