CAJ | 학술논문

针对弱信号条件下传统卫星信号捕获算法无法满足用户需求的问题，在对接收信号进行傅里叶变换的基础上，提出了一种利用四分法估计导航数据比特跳变位和差分相干累加方法相结合的北斗弱信号捕获新算法。与基于FFT的半比特交替和相干累加结合的捕获方法比较可知，该算法数据利用率高，对噪声有良好的抑制效果。仿真结果表明，该算法可实现－38 dB信噪比条件下的北斗弱信号捕获，并可进一步提高软件接收机灵敏度。
침대약신호조건하전통위성신호포획산법무법만족용호수구적문제，재대접수신호진행부리협변환적기출상，제출료일충이용사분법고계도항수거비특도변위화차분상간루가방법상결합적북두약신호포획신산법。여기우FFT적반비특교체화상간루가결합적포획방법비교가지，해산법수거이용솔고，대조성유량호적억제효과。방진결과표명，해산법가실현－38 dB신조비조건하적북두약신호포획，병가진일보제고연건접수궤령민도。
In order to solve the inability of the traditional satellite signal acquisition algorithm to meet the prac-tical requirements under the condition of BD weak signals, a novel algorithm based on FFT is proposed, which uses the differential coherent accumulation method and estimates the position of the navigation data bit-flip by the Quarte-ring algorithm.With a high data utilization ratio, this method is robust to the noise as well, as compared with the algorithm with alternating half bits and combination coherent accumulating.The simulation result shows that the pro-posed algorithm can capture the weak signal in BDS under 38 dB SNR and can improve the software receiver sensitivi-ty.