一种新型的高精度Sigma_Delta调制器结构  

A new high-precision Sigma_Delta modulator structure

作　　者：王阁藩 李恺 刘博 王金婵 张金灿 Wang Gefan;Li Kai;Liu Bo;Wang Jinchan;Zhang Jincan(Electrical Engineering College,Henan University of Science and Technology,Luoyang 471023,China)

机构地区：[1]河南科技大学电气工程学院,洛阳471023

出　　处：《电子测量技术》2022年第12期1-5,共5页Electronic Measurement Technology

基　　金：国家自然科学基金(61704049,61804046);河南省科技厅科技计划项目(192102210087,202102210322);河南科技大学研究生质量提升工程项目(2020ZYL-008)资助。

摘　　要：为实现低失真高动态范围的模数转换,提出了一种新型高精度Sigma_Delta调制器系统。首先,设计了一种新型的二阶单环一位量化结构,结构中增加两支前馈路径,并调整了核心积分器和信号加算模块的逻辑关系。同时,为实现量化噪声的二阶整形以及输入信号的无延迟传输,进一步适配和改进了积分器的传输函数。最终,所提出的调制器实现了更高的信噪比和更宽的动态输出范围。基于MATLAB的系统级仿真结果表明,在信号带宽1 kHz、采样信号频率1 024 kHz的条件下,所提出调制器的信噪比为106.6 dB,有效位数为17.41 bit,二次谐波失真为-82.7 dB,动态范围为104.76 dB,整体指标性能良好,为高阶MASH结构Sigma Delta调制器的研发提供了新方向。In order to realize analog-to-digital conversion with low distortion and high dynamic range, a new high-precision Sigma Delta modulator system is proposed. The Sigma-Delta modulator firstly adopts a new type of second-order single-loop one-bit quantization structure, where adds two feedforward paths and adjusts the logical relationship between the core integrator and the adder module. At the same time, in order to realize the second-order shaping of quantization noise and the delay-free transmission of input signals, the transmission function of the integrator is further adapted and improved. MATLAB based system-level simulation results show that, the signal-to-noise ratio(SNR) of the proposed modulator is 106.6 dB, the effective number of bit(ENOB) is 17.41 bit, the second harmonic distortion is-82.7 dB and the dynamic range is 104.76 dB under the conditions of sampling signal frequency of 1 024 kHz and input signal bandwidth of 1 kHz, which provides a new direction for the research and development of Sigma-Delta modulator with high-order MASH structure.

关 键 词：模数转换器 二阶Sigma-Delta调制器 传输函数 低失真 高动态范围 

分 类 号：TN713[电子电信—电路与系统] TN761