时间交替数据采集系统中存在偏置、增益和时间误差，这严重影响了采集系统的信纳比（SINAD）和有效位数（ENOB）。本文提出频域内的误差校正方法，针对增益误差和时间误差的校正。由存在误差时频域的幅度和相位值得到误差的估计值，推得相应的校正值后进行增益和时间误差的校正。通过对比校正前后信号的频谱来证明该校正方法的有效性。实验结果表明，该算法简单容易实现，将采集系统的信纳比提高到了41.02 dB，有效位数提高到了6.52 bit，校正效果不差于正弦拟合的方法。
The offset error, gain error and time error greatly degrade the Signal to Noise and Distortion Ratio (SINAD) and effective number of bits (ENOB) in time-interleaved data acquisition system. This paper discussed spectrum analysis calibration method for Time-interleaved data acquisition system, which is used for calibration of gain error and time error. The magnitude and phase in special frequency point can be used for estimation of gain error and time error, then the calibration can be achieved. The difference before and after calibration proves the effectiveness of the calibration method. As a result, this method can be achieved easily, the SINAD can reach 41.02 dB, ENOB can reach 6.52 bit. Moreover，the result is no worse than the sine fitting method.
2018,40(11): 139-143 收稿日期：2018-02-05
DOI：10.3404/j.issn.1672-7649.2018.11.028
分类号：TN957.52;TH85
作者简介：余跃听(1971-),男,高级工程师,主要从事舰船综合电力系统的研究与设计
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