TIADC系统误差联合测量及补偿方法

A Joint Measurement and Compensation Method for Errors of TIADC System

针对时间交替并行采样系统通道间存在增益误差和时钟失配误差问题,提出一种误差联合测量方法。该方法利用了测试信号的特性,同时测量2种误差。与已有算法相比,算法结构简单,精度较高。同时根据时钟失配误差产生原理,设计了基于Farrow结构的分数延迟滤波器补偿算法,针对Farrow结构局限于Nyquist带宽的问题,设计了多通道的补偿结构。仿真实验表明,系统的无杂散动态范围得到明显抑制,输出的信纳比至少提高了25dB。

To solve the problem of gain error and timing-skew mismatches among channels of time-inter- leaved analog-to-digital converter（TIADC） system, a joint measurement method of mismatches error is proposed. By making full use of the characteristic of the test signal, this method can measure two kinds of errors simultaneously. Compared with the existing algorithm, the measurement algorithm is simple and more effective. According to the principle of timing-skew, the compensation method of fractional delayed filter based on Farrow structure is designed. Because of the problem of limited Nyquist bandwidth of Far- row structure, a multi-channel compensation structure is designed. After compensation, the output SINAD of the system is increased by at least 25dB.