Implementation of Double-Side Calibration and Measurement for Q-Band 50GHz Application

The double-side calibration and measurement on probing system for single-end and differential signals are presented in this paper. The common calibration kit in the market is including below patterns: Open, Short, Load, and Thru for SOLT/SOLR standard calibration method, but there is still no standard thru/reciprocal pattern for double-side measurement system now, therefore we design a reciprocal kit which is applicable for GSG-150um and GSGSG-150um RF probe and the frequency is up to 60GHz. The reciprocal kit is designed in the 4-layer stack up and simulated in ANSYS HFSS software, the return loss is under -10dB from DC to 60GHz frequency range, and the insertion loss is -0.6dB at 60GHz. The actual measurement results after calibration with SOLR showed -10dB of the return loss under 60GHz, and -1dB of insertion loss at 60GHz. Finally, we successfully calibrated the double-side differential system by the reciprocal kit in Q-band 50GHz and measured the two transmission lines with total 36mm length. First transmission line is all built in one layer, and the second one is divided in two layers. The measurement results showed the trace in one layer is better about 0.56dB at 30GHz.