【摘要】 时间失配误差是时间交替并行采集系统的失配误差中最主要且影响最大的误差。针对该问题,提出了一种基于Farrow结构分数延迟滤波器结合自适应估计对时间失配误差进行数字校正的方法。分数延迟滤波器可以在有限带宽信号采样点之间进行插值。该方法可以对奈奎斯特频率以内的输入信号进行补偿校正,同时适用于任意通道数的时间交替ADC。仿真结果表明,该方法能够对时间失配误差进行精确估计,同时能够有效地抑制杂散分量,校正效果良好。最后,在实际的时间交替采集系统中验证了该方法的有效性。更多还原

【Abstract】 Timing-mismatch error is the most important error and has great influence in the mismatch errors of timeinterleaved parallel acquisition systems,which can greatly degrade the dynamic range of time-interleaved analog-todigital converters( TIADCs). In this paper,a novel digital calibration method for the inter-channel timing-mismatch error is proposed,which is based on Farrow structure fractional delay filter combined with adaptive estimation technique. For the purpose of online correction,the timing mismatch errors are obtained adaptively. The mismatch errors are corrected with the fractional delay filter developed in the form of Farrow structure. The proposed method could calibrate the band-limited signals in the first Nyquist zone,and could be used in the TIADC with any number of channels. The simulation experiment results show that the proposed method can estimate the timing-mismatch error accurately,effectively restrain the spurious spurs and has good calibration effect. The effectiveness of the proposed method was verified in an actual time-interleaved acquisition system.更多还原