The invention discloses a joint
estimation and real-time
correction method for channel error of a time-interleaved ADC (TIADC)
system. The method for implementing joint
estimation comprises the steps of: sampling a single-tone
signal with input frequency of f0 to obtain a sampling sequence xk(n) of various channels of the
system, wherein k=0, 1, L M-1; performing
fast Fourier transform (FFT) on sampling data x(n) which is reduced into a single-tone
signal after the split joint; and in an FFT result, selecting a value FAk at the position where the frequency is 1fs / M+ / -f0,1=0, 1L M-1 and selecting a value FBk at the position where the frequency is 1fs / M,1=0, 1L M-1 to perform inverse
fast Fourier transform (IFFT) to obtain M complex numbers, namely IAk and IBk, and finally, obtaining the joint
estimation on
time error delta tk,
gain error gk, and offset error ok, k=0, 1, L M-1 through
phase angle extraction and a modulus operation
algorithm module. The method for implementing real-time correction comprises the step of: utilizing a comprehensive correction mechanism formed by a
subtractor, a divider and a
fractional delay filter to correct the offset error, the
gain error and the
time error existing in the sampling data of the channels respectively. By the method, joint estimation is performed on the three errors, SFDR of the sampling sequence is improved through the real-time correction, and a filter coefficient is not required to be updated or a correction module is not required to be redesigned even if channel errors are changed, so the aim of the real-time correction is fulfilled.