数字波束形成微波辐射计的灵敏度  

Sensitivity of a microwave radiometer with digital beam-forming

作　　者：张靖[1] 李青侠[1] 郭伟[1] 朱耀庭[1] 

机构地区：[1]华中科技大学电子与信息工程系,湖北武汉430074

出　　处：《华中科技大学学报（自然科学版）》2009年第12期5-8,共4页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：航天技术创新基金资助项目(20060112)

摘　　要：从信号检测的角度出发,分析了数字波束形成辐射计输出信号的数学期望和方差.在此基础上推导数字波束形成微波辐射计灵敏度公式,并与全功率辐射计、综合孔径辐射计进行了比较.分析结果表明:观测点源时,由于接收天线和通道数量的增加,数字波束形成辐射计的灵敏度要优于全功率辐射计;观测展源时,受阵列方向图的影响,数字波束形成辐射计的灵敏度比全功率辐射计的灵敏度要差;与综合孔径辐射计相比,两者的灵敏度是一致的.From signal detection, the mean and variance of signal of the output of a digital beam-forming microwave radiometer are analyzed. Comparison with the sensitivity of total-power radiometer and synthetic aperture radiometer, the formula for the sensitivity of the radiometer is presented, and is compared with the results show that in the case of point source measurements, the digital beam-forming radiometer has higher sensitivity than the total-power radiometer because of the increased number of receive antennas and channels, and in the case of distributed source measurements, digital beam-forming radiometer has lower sensitivity than the total-power radiometer by the effect of array pattern. And the sensitivity of the digital beam-forming radiometer is equal to that of the synthetic aperture radiometer.

关 键 词：辐射计 波束形成 灵敏度分析 辐射接收机 综合孔径辐射计 实孔径辐射计 

分 类 号：TN925[电子电信—通信与信息系统]