四分法和差分相干结合的北斗弱信号捕获算法  

Quartering and Differential Correlation-Combined Algorithm for BD Weak Signal Acquisition

作　　者：牛家红 樊昌周[1] 李宏伟[1] 

机构地区：[1]空军工程大学信息与导航学院,陕西西安710077

出　　处：《电子科技》2015年第9期11-15,共5页Electronic Science and Technology

摘　　要：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 d B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。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 sensitivity.

关 键 词：四分法 比特跳变位估计 弱信号捕获 差分相干累加 

分 类 号：TN911.7[电子电信—通信与信息系统]