A calibration method for frequency response mismatches in M-channel time-interleaved analog-to-digital converters

抄録

Frequency response mismatches (FRMs) in time-interleaved analog-to-digital converters (TIADCs) generate undesired spurs degrading the performance of TIADCs. This paper introduces a digital calibration method for the FRM in M-channel TIADCs (M-TIADCs). This method exploits fixed differentiator finite-impulse response (FIR) filters and the Hadamard transform to reconstruct the mismatch induced error signal. The mismatch parameters are estimated utilizing a short training signal and the least square (LS) method. Our method is simpler in terms of implementation compared with conventional methods as cumbersome time-varying filters, complex signal processing and front-end hardware modifications are avoided. Numerical simulation results demonstrate the efficacy and efficiency of the proposed method.