摘要
与综合孔径复相关接收不同,镜像综合孔径辐射计只需测量同相相关输出,为此镜像综合孔径辐射计与综合孔径辐射计的接收机结构也有明显区别,而镜像干扰分析对于辐射计接收机结构及单双边带选择尤为重要.为了分析镜像综合孔径辐射计接收机结构及单双边带选择,本文首先介绍了镜像综合孔径辐射计的接收机结构,然后从镜像综合孔径接收信号角度出发推导了镜像综合孔径辐射计接收机结构分别选择单、双边带工作模式下接收机通道相关函数表达式,分析其是否会产生镜频干扰.理论推导发现,镜像综合孔径辐射计在单、双边带工作模式下,都不会产生镜像干扰,唯一的区别在于双边带重建亮温的幅度是单边带的2倍.这是与综合孔径辐射计接收机结构在下变频、再I/Q解调且选择双边带模式时会产生镜像干扰最大的不同.最后,通过双点源和展源仿真验证了理论的正确性.研究结果可为实际应用中镜像综合孔径辐射计接收机单双边带选择提供参考.
Different from the complex correlation of aperture synthesis radiometers(ASR),the in-phase output of the mirrored aperture synthesis radiometers(MASR)is measured.Therefore,the receiver configuration of the MASR and ASR is different.In order to analyze the choice between single-band and double-band of MASRs,firstly,the receiver configuration of the MASR is presented.Then,from the perspective of the signal processing of the MASRs,the cross-correlations for two modes are computed,and it is analyzed that whether or not the mirror-image interference is produced when the MASR images the targets at single-side band and double-side band mode.The theoretical results show that the mirror-image interference is not produced at single-side band and double-side band modes,the only difference is that the amplitude of double band for MASR is twice that of single-band,which is different with that when the ASR with I/Q demodulation after down-conversion receiver configuration image the targets at double-side band,the mirror-image interference is produced.Finally,the simulations of two point sources and rectangular source are carried out to verify the correctness of the theory.Research results provide a reference for the choice of the receiver configuration of MASR.
作者
朱四华
李育芳
刘丹丹
ZHU Sihua;LI Yufang;LIU Dandan(Naval University of Engineering,Wuhan 430033,China)
出处
《电波科学学报》
CSCD
北大核心
2022年第5期905-910,共6页
Chinese Journal of Radio Science
关键词
镜像综合孔径辐射计
接收机结构
单边带
双边带
镜像干扰
mirrored aperture synthesis radiometer
receiver configuration
single-sideband
double-sideband
mirror-image interference
