基于频域稀疏性的时间交替模数转换器时间相位失配盲测量算法  

A Blind Timing Skews Estimation Algorithm of Time-interleaved Analog-to-digital Converters Based on Spectra Sparsity

作　　者：徐祥俊[1] 邹月娴[1] 

机构地区：[1]北京大学深圳研究生院现代数字信号处理实验室

出　　处：《电子与信息学报》2012年第9期2241-2246,共6页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(60775003)资助课题

摘　　要：该文研究时间交替模数转换器(TIADC)的通道间时间相位失配参数的盲测量问题。基于TIADC系统架构、输入模拟信号的频域稀疏性和非混叠频率点,以采样定理和欠采样理论为基础,探索TIADC系统输入信号、输出信号以及与子ADC输出信号之间的频谱关系,推导出了一种新的基于非混叠频率点的相对频谱的离散傅里叶逆变换序列的相位信息的TIADC通道间时间相位失配参数的盲测量算法。仿真实验表明该文所提出的盲测量算法具有可以与正弦拟合算法相比拟的参数测量精度,并且具有对噪声不敏感,对输入信号频率无限制,对TIADC系统通道数无限制,不需要对输入信号过采样等突出优点。TIADC系统真实捕获数据测试进一步验证了该算法的准确性和有效性。The blind Timing Skews Estimation （TSE） issue for the Time-Interleaved Analog-to-Digital Converters （TIADC） is investigated in this paper. Accordingly to the TIADC configuration, the spectra sparsity of the analog input signal, and the non-overlapping frequency points, the spectra relations among the input signal of the TIADC, the output of the TIADC and the output of the sub-ADCs are explored based on the sampling theorem and the undersampling theory. A novel blind timing skews estimation Mgorithm is developed by using the phase information of the resultant sequence of the Inverse Discrete Fourier Transform （IDFT） of the relative output spectrum ratio at the non-overlapping frequency point. The simulation results show that the proposed TSE algorithm has the comparable parameter estimation performance of the sin-fit algorithm. Moreover, the proposed algorithm offers some desired properties, such as robustness to the additive noise, no limitation to the frequency of the input signal, no constrains on the channel number of the TIADC and no requirement on oversampling of the input signal. The experimental result using the captured data of a developed TIADC prototype validates further the high accuracy and effectiveness of the proposed TSE algorithm.

关 键 词：时间交替模数转换器 时间相位失配 盲测量 欠采样 频域稀疏性 

分 类 号：TN792[电子电信—电路与系统] TN911.72