摘要
传统载波频率估计算法对降采样数据非线性变换后,直接快速傅里叶变换以获取载波多普勒频移,方法虽然简单,但精度较差,不适用于高动态、弱信号等复杂环境。本文提出一种改进的载波频率估计算法,对降采样数据进行多普勒频移、多普勒变化率的双重补偿和调制类型的模式识别,提高载波频率的搜索范围和测量精度;在粗测频、精测频状态对第一级降采样数据频率预补偿后进行第二级降采样处理,以适当缩短测频状态的搜索时间。最后通过试验分析表明:该算法在高动态环境下可大幅度提高多普勒频移及其变化率的估计性能。
The fast fourier transform( FFT) is directly used to achieve the carrier Dopplor shift after non-linearly transforming the sampled data in traditional estimation algorithm for carrier frequency,and this method is hardly adapted to high dynamic and weak signal environment as a simple but poor-precision method. A new optimized estimation algorithm for carrier frequency is proposed. In order to improve the search scope and the measure precision of the carrier frequency,the carrier Dopplor shift is used and its rate double compensate the sampled data and recognizes the modulation type,which can properly shorten the search time of the measure state. It achieves the second sampled data after using the rough carrier frequency that pre-compensate the first sampled data in the coarse and fine measure state. The validity of the algorithm is verified by theoretical analysis and performance experiment. The results show that the algorithm can effectively improve the estimation performance of the carrier Dopplor shift and its rate under high dynamic condition.
作者
金磊
Jin Lei(Southwest China Institute of Electronic Technology,Chengdu 610036,China)
出处
《航天控制》
CSCD
北大核心
2018年第6期47-52,共6页
Aerospace Control
关键词
高动态
载波频率
双重补偿
精确估计
High dynamic
Carrier frequency
Double compensate
Accuracy estimation
