Handy Calibration Substrate for Both Horizontal and Vertical Probing

article proposes a vovel substrate for a handy SG-GS/SG-SG calibration in both horizontal and vertical probing measurement. The proposed substrate provides two ways of probing for "through" calibration in horizontal and vertical positions without changing the probe holders. It has "through" lines vertically and horizontally using vias and traces, respectively, and both "through" lines were designed to satisfy 50 ohms of characterization impedance. A prototype of the proposed substrate was fabricated using FR4 and then tested in the horizontal calibration resulting in the successful reproduction of all the S-parameters in the horizontal meander test board. It was also tested in the vertical calibration, and was successful to re-produce all the coupling effects in via arrays, demonstrating the effectiveness and handiness of the proposed calibration substrate.