Abstract The article analyzes the sensitivity of unmatched receiving coil for the NMR scanner. Receiver of the scanner was investigated from the point of view of noise features. Theory of the noise figure has been modified to utilize the receiver for digitization of its own noise and the noise figure calculation. The resulting noise figure has been measured with different source impedances and the optimal value has been acquired. Influence of the noise figure on the resulting signal-to-noise ratio has been calculated for the sensitivity judgement. The output SNR has been investigated for constant input SNR as well as for constant input voltage. Many results are depicted in figures. Also examples of theoretical results are depicted graphically.

中文翻译：

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用于核磁共振实验的简单噪声匹配接收线圈的灵敏度分析

摘要 分析了核磁共振扫描仪非匹配接收线圈的灵敏度。从噪声特征的角度对扫描仪的接收机进行了研究。噪声系数理论已被修改，以利用接收器对其自身噪声进行数字化并计算噪声系数。已使用不同的源阻抗测量所得噪声系数并获得最佳值。已计算噪声系数对所得信噪比的影响用于灵敏度判断。已针对恒定输入 SNR 以及恒定输入电压研究了输出 SNR。许多结果在图中描述。还以图形方式描述了理论结果的示例。