卫星导航有源接收天线噪声温度测量

Global Navigation Satellite Systems (GNSS) Active Antenna Noise Temperature Measuring Device

卫星导航有源接收天线的噪声温度是导航接收系统的关键技术指标之一。针对卫星导航有源天线总体噪声温度无法测量的问题,研制了两台口面型噪声源,口面噪声源主要由辐射体、辐射体物理温度控制和温度测量仪等组成。两个口面噪声源在L和S波段分别提供高低温标准噪声温度,采用Y系数测量方法测量有源接收天线的总体天线噪声温度。测量了某卫星导航有源天线的总噪声温度,在(1.19~1.29) GHz的频率范围内,中心频率1.24 GHz上噪声温度测量结果为206 K,但是在1.266 GHz频率点上噪声温度测量大于4 000 K,说明天线与滤波器之间、滤波器与放大器之间存在设计问题或其它问题,体现出测量有源天线噪声温度的必要性。

The noise temperature of satellite navigation active receiving antenna is one of the key technical indexes of navigation receiver.In order to solve the problem that the overall noise temperature of the satellite navigation active antenna cannot be measured, two surface type noise sources are developed.The surface type noise source is mainly composed of radiator, radiator physical temperature control and temperature measurement instrument.The two surface type noise sources provide the high and low standard noise temperature in L band and S band.The noise temperature of active receiving antenna is measured by Y-Factor method.The noise temperature of a satellite navigation active antenna is measured.In the frequency range of(1.19~1.29) GHz, the noise temperature measurement result is 206 K at the center frequency of 1.24 GHz.However, the noise temperature measurement result is greater than 4 000 K at the frequency of 1.266 GHz, which indicates that there are design problems or other problems between the antenna and the filter, and between the filter and the amplifier, reflecting the necessity of measuring the noise temperature of the active antenna.