A Ultra-Wideband All-Passband Phase Calibration Algorithm

As a parallel sampling architecture, digital bandwidth interleaved can effectively improve the sampling rate and bandwidth of the system. However, in the digital bandwidth interleaved sampling system, the phase nonlinear characteristics of the analog filter and the delay of the digital filter will cause the frequency response of the combined system to still have a nonlinear phase or an uneven group delay characteristic. This uneven group delay characteristic causes phase distortion in wideband signals. Therefore, this paper proposes a new all-passband phase calibration algorithm to solve the phase-frequency response distortion in the digital bandwidth interleaved acquisition system. Finally, the system meets the 40GSPS sampling rate, 10GHz bandwidth and the frequency response fluctuation of the passband is within 3 dB. Input the standard fast edge signal into the system, and use the parameter measurement function of the system, the rising time of the system from 10 % to 90 % is 34.2ps and the shape has no obvious distortion. The experimental results verify the effectiveness of the algorithm proposed in this paper.