关键词: 时间交替模数转换, 采样时间误差, 最小均方差

Abstract:

Timing mismatches in time-interleaved ADCs (TIADC) greatly degrade the spurious-free dynamic range (SFDR) of this system.For calibrating timing mismatches, based on the spectra relation between the analog input signal and the output signal of the TIADC system, a blind timing mismatch calibration algorithm is proposed by eliminating the error signal in the output signal.By expanding the frequency expression of output signal in Taylor approximation, this algorithm can construct the ideal output signal.By introducing least mean square (LMS) for estimating timing mismatch, this proposed algorithm is aimed at reducing the complexity of hardware and improving the accuracy of calibration algorithms.Experiments show that this algorithm can easily extend to an arbitrary number of channels and improve the SFDR of the output signal about 47dB.

Key words: time-interleaved analog-to-digital converter (TIADC), timing mismatch, least mean square (LMS)