一种 TIADC 系统误差自适应联合补偿算法

针对时间交替并行采样系统(time-interleaved analog-to-digital converter,TIADC)通道间存在直流偏置误差、增益误差和时钟失配误差的问题,提出一种基于自适应的误差联合补偿算法.该算法设计了新的系统时序和基于子通道的误差补偿模型,采用多输入的自适应结构,实现对3种误差的联合补偿.理论分析和仿真结果表明,新算法结构简单,运算量小,具有良好的抗噪声性能,同时算法对带通信号有良好的适用性.当ADC量化位数为16时,系统的信纳比能够提升约37 dB,无杂散动态范围能够提升约50 dB.

Joint adaptive algorithm for compensation of channel-mismatches in TIADC

In order to solve the problem of the offset, gain and timing-skew among the channels of time-interleaved analog-to-digital converter (TIADC), an adaptive method is proposed. The algorithm designs a new time sequence and a calibration model based on sub-channel using the multi-input adaptive structure and realizing joint calibration for the three errors.Through the theoretical analysis and simulation results show that the new algorithm has simple structure, small computation and good anti-noise performance. Moreover, the algorithm has good applicability for band-pass signal, when the ADCs outputs are quantized to 16 bits, the SNDR of the output can be raised around 37 dB, and the SFDR of the output can be raised around 50 dB.