Wideband SMA-Coplanar Waveguide Transition Based on Impedance Compensation Method

This paper proposed a novel wideband SMA-coplanar waveguide (CPW) transition based on impedance compensation method, while electromagnetic simulation based on time domain reflectometer (TDR) is employed. Stepped inner conductor is used to lower the parasitic parameters, while mounting hole on shielding box is also designed as stepped structure and its dimensions are optimized to compensate the capacitance introduced by the step structure. Back to back model of proposed transition is simulated at frequency domain, from 2 GHz to 18 GHz. The results shown that, the return loss of the structure is better than 15 dB, and insertion loss is better than 0.6 dB though the working band. The proposed transition is easily to fabricate under normal mationing procedure, and provide a low cost and high performance connection method for radio frequency (RF) applications.