时间交替ADC系统的实现

时间交替ADC系统通过几片低速的ADC芯片进行并行交替采样,可以成倍地提高系统的采样频率,同时保持较高的分辨率1]。但是由于芯片及具体实现过程中一些实际因素的影响,不可避免地会引入通道失配误差2]。本文利用两片ADC芯片及外围电路来实现时间交替ADC系统,并通过Matlab软件对采样数据进行通道失配误差的估计和校正。Matlab仿真结果表明,该系统的采样率基本上达到了单片ADC的两倍,同时其通道失配误差通过算法校正后得到了有效地消除。

The realization of time-interleaved ADC system

The ADC sampling system constituted by a few slices of low-speed ADC chip can exponentially increase the sampling rate based on the time-interleaved algorithm, and basically remain the resolution invariably. But because of the chips itself and the influence of the practical factors during the design process, there will always be channel-mismatch errors in the system. In this paper, the time-interleaved ADC system is realized with two ADC chips and other peripheral equipments, and then the channel mismatch errors of the sampling data will be estimated and calibrated by Maltab software. The experimental results of Matlab simulation show that the sampling rate of the system mainly reaches twice of the one using monolithic ADC and its channel mismatch errors are eliminated effectively though the calibration algorithm.