Fine frequency grid calibration and the experiment for NVNA based on squared crystal

This paper studies on the low phase resolution of the phase calibration of a mixer-based two-port coaxial Nonlinear Vector Network Analyzer (NVNA), especially the absolute calibration techniques. A new method of fine frequency grid calibration based on squared crystal detector has been made. The narrowband calibration principle of the way to calibrate the NVNA by using the squared crystal detector is deduced, and the calibration process is given. Simulation results of ADS and the experiment prove the effectiveness of the proposed method, and its phase calibration resolution achieves 100KHz.