A five-item MSLD windowed triple-spectrum-line interpolated FFT algorithm for measuring SFDR

Measuring the spurious free dynamic range (SFDR) of analog-to-digital converters (ADCs) by the fast Fourier transformation (FFT) has difficulties in performing coherent sampling and integral period truncation. The non-coherent sampling is inevitable, and the SFDR measurement results may be disturbed by the spectral leakage and the picket fence effect (PFE). We propose a triple-spectrum-line interpolated FFT algorithm based on a five-item cosine window with the maximum side lobe decay speed to reduce the errors caused by the spectral leakage and PFE. The verification platform is constructed based on MATLAB, and the behavior-level dynamic models of typical high-speed ADCs are employed for simulation and verification. Results show that the proposed method can achieve the similar measurement accuracy as the standard coherent sampling FFT method with significantly reduced test cost.