Signal acquisition of Luojia-1A low earth orbit navigation augmentation system with software defined receiver

Low Earth Orbit (LEO) satellite navigation signal can be used as an opportunity in the case of a Global Navigation Satellite System (GNSS) outage, or enhancement by means traditional GNSS positioning algorithms. No matter which service mode is used, acquisition prerequisite for providing enhanced LEO services. Compared with medium orbit satellite, transit time shorter. Thus, it great significance to expand successful range signal. Previous studies on are based simulation data. However, research real data crucial. In this work, characteristics satellites: power space density free and Doppler shift satellites individually studied. The unified symbolic definitions several integration algorithms parallel search algorithm given. To verify these acquisition, Software Defined Receiver (SDR) developed. performance expanding verified collected from Luojia-1A satellite. experimental results show that strategy range, will not indefinitely duration. coherent differential better than other two algorithms, so recommended 20 ms duration preferred. detection threshold 2.5 suitable all various durations, especially Maximum-to-Mean Ratio indicator.