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本文研究在无商用噪声标准情况下,毫米波辐射计(零平衡Dicke式天线通道噪声注入型)接收机定标的实用技术、方法及有关理论问题。导出了校准源的馈线温度非均匀分布时,校准源-馈线组合的有效输出噪声温度的计算公式,并对其结果进行了讨论。对参考温度因环境而变化所造成的影响也进行了讨论,并给出此种情况下天线温度测量值的正确推算式。阻抗失配的影响虽未讨论,但所给T_A～X和T_N～Y定标曲线已对此影响进行了修正;所提供的基本校准方法及讨论所得结论都适用于限抗失配情形。
This paper studies practical techniques, methods and related theoretical issues of millimeter-wave radiometer (zero-balanced Dicke antenna channel noise injection type) receiver calibration without commercial noise standard. The calculation formula of the effective output noise temperature of the calibration source-feeder combination when the feeder source temperature distribution is inhomogeneous is derived and the results are discussed. The influence of the change of the reference temperature on the environment is also discussed, and the correct calculation formula of the antenna temperature measurement in this case is given. Although the influence of impedance mismatch has not been discussed, the calibration curves given to T_A ~ X and T_N ~ Y have been corrected. The basic calibration methods provided and the conclusions obtained from the discussions are applicable to the case of the impedance limited mismatch.