Adaptive blind compensation of timing mismatches in four-channel time-interleaved ADCs

The time interleaved method is an efficient solution to breakthrough the interface speed bottlenecks in optical communication. But it´s sensitive to the mismatches between the interleaved channels. We introduce a blind adaptive method to correct the timing errors in a four-channel time-interleaved analog-to-digital converter (TIADC). The proposed error estimation method is based on the correlation ship between the output samples of every two adjacent sub-ADCs. The calibration method is based on the Taylor series expansions, we can eliminate the error component approximatively by subtracting the high order terms of the Taylor series expansions from the error module and remain the signal component. The calibration module employs filters of paralleled structure, which can reduce the processing speed of the hardware effectively. With the approach as just mentioned, we can improve the calibration system´s scalability. The experiment results with the real TIADC output data validates its good performance.