【摘要】 介绍了Y因子法测量天线噪声温度的原理方法,分析了常温负载和低噪声放大器噪声温度的不确定性对天线噪声温度测量的影响,推导了天线噪声温度测量的绝对误差计算公式,研究了低噪声放大器噪声温度对天线噪声温度测量精度的影响,提出了改善天线噪声温度测量精度的方法。最后,给出了65 m射电望远镜天线L波段、C波段和X波段噪声温度测量结果。测量结果的误差分析表明:65 m射电望远镜天线噪声温度测量的绝对误差≤±2.48 K。更多还原

【Abstract】 In this paper, the measurement principle and procedure for the antenna noise temperature by Y-factor method are described. The effect of uncertainties for ambient load and low-noise amplifier noise temperature on antenna noise temperature measurement is analyzed, and the absolute error formula of antenna noise temperature measurement is derived. The effect of the noise temperature of LNA on the measurement accuracy of antenna noise temperature is studied, a method to improve the measurement accuracy of antenna noise temperature is presented. Finally, the measured results of the noise temperature of 65 m radio telescope antenna at L-band, C-band and X-band are given. The error analysis of the measurement results shows that absolute error of antenna noise temperature measurement of the 65 m radio telescope is ≤±2.48 K.更多还原