基于等效采样的TIADC通道失配校准方法

本文针对TIADC(时域交替模数转换器)的通道失配校准存在过程复杂、计算量大的问题,设计了一种高效的通道失配校准方法。基于等效采样原理,将单个ADC多个周期的采样数据重叠显示在一个周期内,通过比较各个ADC重叠波形的平均值、幅值范围和相位,即可实现同时校准偏移失配、增益失配和时间失配,免除了频域转换或正弦拟合等步骤。仿真和实际测试结果表明,本文方法能准确测量上述失配误差,在显著提升TIADC性能的同时,能有效降低校准的复杂性,减小运算量。

Correction method for channel mismatches errors in TIADC system based on the principle of equivalent sampling

This paper proposes an efficient channel mismatch correction method for TIADC (time interleaved analog to digital converter) system, in order to overcome the complexity and inefficiency of the conventional correction method. Based on the principle of equivalent sampling, the sampling data of a certain number of cycles is overlapped to one cycle high resolution data, from which all parameters needed to correct channel mismatch, such as average value, amplitude range and phase, can be acquired. According to these parameters, the proposed method can correct offset error, gain error and time skew directly, so avoid the great calculation of FFT or curve fitting. Simulation and application results show that the method can measure above mentioned errors rightly and enhance the performance of TIADC efficiently, at the same time, reduces the complexity and calculation.