Statistics-Based Correction Method for Sample-and-Hold Mismatch in 2-Channel TIADCs

Abstract

Sample-and-hold (S/H) mismatches incur undesired error which affects the time-interleaved analog-to-digital converter(TIADC)‘s performance. A few calibration methods have been proposed for S/H mismatches which either need training signals or cannot apply to the signals with narrow frequency range around the center of the Nyquist band. This paper proposes a statistics-based correction algorithm for S/H mismatch in 2-channel TIADCs. The mismatch parameter is identified by assuming the modulo two quasi-stationary property of the input samples, and the mismatch-induced error is reconstructed by employing variable multipliers and differentiators in Richardson iteration. Simulation results illustrate the effectiveness of the proposed method and the advantage to the method based on input-free band (IFB).