Accurate Attenuation Determination with One-Port Measurements

This paper presents a one- port measurement to reconstruct the scattering matrix (S-matrix) of a two-port network by a frequency-shift method. This method would simplify the test sequence and keep the acceptable tolerance to measure the attenuation of a two-port device under test (DUT). An auxiliary circuit is implemented to respond to different impedances at different frequencies as a terminator at the second port of the two-port DUT. Formulation to reconstruct the two-port DUT is presented. This one-port measurement method provides acceptable accuracy in measuring attenuation coefficients compared to the conventional two-port method. The formula of the reconstructed two-port S-matrix is verified by experiment in the frequency range from 8 GHz to 12 GHz.