A New Fast Convergent Blind Timing Skew Error Correction Structure for TIADC

Abstract

The timing errors and especially the timing skew mismatch errors are one of the main errors that cause substantial degradation in the resolution of high-speed Time-Interleaved analog-to-digital converters (TIADCs). These errors cannot be completely corrected using blind methods such as ANC, BSS etc., because of the correlation between the desired signal and the noise as both are sampled from the same input signal. In this brief, a new algorithm using oversampling is proposed to guarantee independence between the signal and the noise. The compensation structure is a typical Adaptive Noise Cancelling (ANC) block which uses special cost function gained from the oversampling concept. To estimate the noise signal caused by the timing skew error, a new structure using modulation concept is derived from the reformulation of the timing skew error effect on the TIADC signal and oversampling assumptions. The simulation results are presented for a four-channel 10-bit TIADC in order to verify the effectiveness of the proposed method. Low computational complexity and fast convergence speed are the main advantages of the proposed algorithm.