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Wafer Probe Transducer Efficiency



Dylan F. Williams, Roger Marks, Dave K. Walker, Fred R. Clague


Experimental evidence is presented that shows the conventional expression relating the transducer efficiency of a two-port to measured scattering parameters is incorrect when the characteristic impedance at one of the ports is complex. This evidence is based on the measurement of the power from a microwave source transferred through a probe to a lossy coplanar waveguide. The conventional expression differs from the measurement by up to 20%. An alternative expression, accounting for the complex characteristic impedance, gives accurate results.
IEEE Microwave and Guided Wave Letters


Williams, D. , Marks, R. , Walker, D. and Clague, F. (1992), Wafer Probe Transducer Efficiency, IEEE Microwave and Guided Wave Letters, [online], (Accessed June 23, 2024)


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Created October 1, 1992, Updated November 10, 2018