Combined coherent acquisition method performed two navigation signals

At present, the Global Navigation Satellite System (GNSS) receivers require improved acquisition sensitivity to extend the boundary of their application ranges. Under the background that each GNSS begins or plans to broadcast multi-frequency signals, combined acquisition utilizing multi-frequency signals or multi-beam signals is the effective means to improve the acquisition sensitivity. Combined non-coherent accumulation method is frequently used and characterized by simple algorithm and low resource consumption, but is not applicable to uncertain signal-to-noise power ratio. This paper analyzes in detail the theoretical influence of inter-signal phase difference and power ration the performance of combined coherent acquisition method, makes simulation experiments, and proves the effectiveness of combined coherent acquisition method.