Broad-band CPWG to stripline feed-through transition and de-embedding method for millimeter wave measurement

Abstract

A broadband coplanar waveguide with ground to stripline transition with high performance is designed and implemented, which can work at DC or a frequency up to 40 GHz. The ground-signal-ground probe test is a widely used method for accurate measurement of millimeter wave device. Because the probe pitch is smaller than the best dimension of the transition, a 50Ω connector fabricated by Gallium-Arsenic technology was introduced as the bridge between the transition and the probes. In order to acquire accurate measurement result, de-embedding method is adopted. The measurement results show that the insertion loss of the entire transition path is less than 0.5 dB and the return loss is better than −14.5 dB at a frequency up to 40 GHz. Besides, an equivalent circuit model of the transition is also proposed.