Abstract：An analytical model of the crosstalk for the dual channel of attenuation measurement system is derived through analysis on the principle of a double balanced mixer. An experiment of measuring the crosstalk of a dual channel of attenuation measurement system is carried out. The analytical result is in fare agreement with the measurement data. Based on the analytical result, the isolation of the local oscillator channel should be larger than 120 dB in order to make the uncertainty of the crosstalk less than 0.01 dB at measurement range of 100 dB. The analytical model is of useful value for the establishment of the dual channel of attenuation measurement system and assessment of uncertainty of the crosstalk.
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2015, Vol. 36 
