Three subjects-UWB radar antenna, UHF/VHF band receivernoisetemperature, and the target detection from background, which are main factors in UWB SAR range equation, are studied.
The conversion loss and noisetemperature of mixers is determined by changing the IF noisetemperature so as to change the noisetemperature of the receiver system.
混频器的变频损耗和噪声温度的测量可以用改变中频部分的噪声温度使接收机的系统噪声温度变化来加以确定。
3
This SIS mixer receiver is reliable, and can achieve good noise performance even operated at 4.3k temperature with a close cycle helium refrigerator.