Calibration of Mismatch Errors in Time-Interleaved A/D Converter System

摘要

Time-interleaved ADC system is a well-known technique that can be used to increase the maximum sample rate. But mismatch between channels, including time-skew error, gain error and offset error, degrades the system performance. Two methods to measure mismatch errors and calibration technique for time-interleaved ADC are proposed in this paper. Measuring errors in time domain is novel and simple, which based on the signal statistical features. To detect mismatch errors in frequency domain, the spectrums of nonuniformly sampled signals are analyzed first. According to the spectrums, we present a FFT and IFFT algorithm to detect the three errors. At last, Farrow structure is adopted to correct the time-skew error and experiment results are presented.