数字干涉仪时域频域鉴相性能对比的理论分析  

Theoretical Analysis on Performance Comparison of Phase Discrimination in Time Domain and Frequency Domain for Digital Interferometer

作　　者：石荣 李潇 邓科 

机构地区：[1]电子信息控制重点实验室,四川成都610036

出　　处：《无线电工程》2016年第10期24-28,共5页Radio Engineering

基　　金：总装共用技术基金资助项目(91X0A210XXX1XDZ390XX)

摘　　要：基于数字干涉仪中鉴相性能理论分析研究的需要,在对其工作原理简要概述的基础上,分别构建了时域和频域鉴相的数学模型,其中的时域鉴相模型同时也反映出与双通道互相关处理的等价性。通过鉴相误差的理论分析,结果表明:2种鉴相方法对干涉仪通道间相位差的估计都具有无偏性;但频域鉴相相对于时域鉴相,其误差的方差更小,在低信噪比条件下这一特点表现尤为明显。理论分析结果与仿真结果完全吻合,从而在理论上证明了频域鉴相的性能优于时域鉴相,也说明了频域鉴相性能优于通道间的互相关处理。The theoretical analysis and research on performance of phase discrimination for digital interferometer are very necessary. After its working principle is briefly introduced,the mathematic models for phase discrimination in time domain and frequency domain are established respectively. The equivalence between phase discrimination in time domain and cross correlation of two channels can be found easily. The theoretical analysis on the error of phase discrimination has shown that both methods provide non-bias estimations for phase difference between channels,but the error variance of phase discrimination in frequency domain is much less than that of the time domain. This characteristic is more obvious in condition of small SNR（ Signal to Noise power Ratio）. The theoretical analysis completely fits the simulation. It is theoretically proved that the performance of phase discrimination in frequency domain is much better than that of time domain,and it is also better than that of cross correlation processing of two channels.

关 键 词：数字干涉仪 时域鉴相 互相关处理 频域鉴相 鉴相性能 

分 类 号：TN971[电子电信—信号与信息处理]