应用于高精度ADC频谱测试的改进加窗技术  

Improved windowing applied to high-precision ADC spectral test

作　　者：付江铎 伍民顺[1] 班诚 郭怡[1] 许江涛[1] Fu Jiangduo;Wu Minshun;Ban Cheng;Guo Yi;Xu Jiangtao(School of Microelectronics,Xi'an Jiaotong University,Xi'an 710049,China)

机构地区：[1]西安交通大学微电子学院,西安710049

出　　处：《电子测量与仪器学报》2020年第5期9-15,共7页Journal of Electronic Measurement and Instrumentation

基　　金：国家自然科学基金(批准号:61774126)资助项目。

摘　　要：在进行模数据转换器(ADC)频谱测试时,通常需要满足相干采样条件。但这一要求的实现较为困难,测试时如果不满足就会发生频谱泄漏现象。为了抑制泄漏,目前最常用的方法是使用加窗技术。但该方法的使用要求较为严格,无法胜任目前高精度ADC的测试,且需要使用者十分熟悉窗函数原理。通过对频谱泄漏和加窗技术进行详尽的理论推导,提出了一种选定合适窗函数类型以及扩展系数(span)的方法,使测试者不需要过多的先验知识。通过所提方法,在窗函数的第一旁瓣高于噪声基底时,仍然能完成高精度ADC的测试工作,扩大了常见窗函数的应用范围。使得常见窗函数如汉宁窗等,也能应用于18位的高精度ADC测试工作。仿真结果显示所提算法在任意非相干程度下仍可得到准确的测试结果,各项参数的最大误差均小于1 dB。同时,使用了一款商用18位ADC实验结果验证了所提算法的可行性。When testing the analog-to-digital converters(ADCs),coherent sampling is required.However,it is difficult to achieve,so spectrum leakage will occur.In order to suppress leakage,the most common method used is windowing.The method is so strict that it is not suitable for the current high-precision ADC test,and the user should be very familiar with the window function.In this paper,a method for selecting the appropriate window function type and the span is proposed.Through the proposed method,accurate test results can still be obtained when the first side lobes of the window function are higher than the noise floor and the application range of common window functions is expanded.This makes common window functions,like Hanning window,can also be applied to 18-bit high-precision ADC test work.The simulation results show that the proposed algorithm can still obtain accurate test results over any level of noncoherency,and the maximum error of each parameter is less than 1 dB.The experimental results of a commercial 18-bit ADC are used to verify the feasibility of the proposed algorithm.

关 键 词：相干采样 动态测试 频谱泄露 窗函数 高精度ADC 

分 类 号：TN407[电子电信—微电子学与固体电子学] TN792