一种多通道采样系统增益误差估计方法

摘要

The multichannel sampling system can solve the contradiction between the conversion rate and quantitative preci⁃sion of analog⁃to⁃digital converter(ADC),thereby the high sampling precision can be ensured while the sampling rate is raised. However, the mismatch error among channels will seriously degrade the performance of system. The early research mainly focused on the time error(static jitter)estimation. The gain mismatch is caused by the different technological process of each DA convertor during the manufacturing process. Similar to the time base error,the gain mismatch can also lead to non⁃linear distortion of sampled signal. A method is proposed to estimate the gain mismatch error by using the second order statistical property of received data vector. The method needs less calculations and is easy to realize. The processing result of the simulation data proved the effectiveness of the method.%　　多通道采样系统可以有效解决单片模数转换器 ADC 转换速率与量化精度的矛盾，从而能够在提高采样率的同时保证采样高精度。但是多通道间的失配误差将严重降低系统性能，早期的研究主要集中于时间误差（静态抖动）的估计，增益失配是由于制造过程中各数模转换器的工艺流程不同引起的。与时基误差类似，增益失配同样将导致采样信号的非线性失真。提出了一种利用接收数据矢量的二阶统计特性来估计增益失配误差的方法，该方法计算量小，易于实现。仿真数据的处理结果验证了该方法的有效性。