Simulation and experimental investigation of jig using semi-rigid cable for S-parameter method

摘要

Recently, the S-parameter method using a vector network analyzer was proposed whereby the differential input impedance of a balanced-fed antenna was obtained. To improve measurement accuracy of the S-parameter method, the dependence on the thickness of the semi-rigid cable used for the measurement jig is obtained from the results of calculations using the FDTD method. Three types of jigs each made from semi-rigid cables of differing thickness were fabricated, and the input impedance of the dipole antenna are calculated and measured using the S-parameter method. The impedances were compared with those obtained from the available theories by King. Results from the S-parameter method was found that using the thinner diameter coaxial cable can be more accurate measurements.