基于matlab的sigma-delta调制器的设计

基于matlab的sigma-delta调制器的设计(论文11000字)
摘要：Sigma Delta ADC（Analog to Digital Converter)主要由 Sigma Delta 调制器和数字滤波器两大部分组成。与其他类 ADC 相比，其优势在于较高的转换精度和较低的功耗。其中， Sigma Delta 调制器对工艺生产中的各种非理想因素具有不敏感性，它对模拟电路设计的指标要求较低，因此已被广泛应用于音频信号的处理之中。此外 过采样和噪声压缩等技术的应用使得Sigma-delta ADC能够实现高精度模数转换。
学者将Sigma-delta ADC与传统模数转换器比较发现，Sigma-delta ADC不仅对模拟电路的性能及器件匹配性要求较低，而且和其它数字电路更容易实现片上集成。因此，Sigma-delta ADC也伴随着片上系统（SOC）的迅猛发展而得到广泛应用。本文从 sigma-delta 调制器的工作原理出发，翔实地论述了以时钟抖动，开关非线性电阻，开关热噪声等非理想因素给调制器性能带来的影响。然后本文根据上述非理想因素推导出对调制器性能影响的时域数学模型，以该模型为基础，借助 MATLAB软件下的 simulink ，分别对一阶、二阶sigma-delta 调制器、进行非理想建模，利用仿真分析的方法，得出各非理想因素对调制器信噪比影响的大小。最后，本文提出了全局优化设计的思想，即为了达到调制器最佳性能，应如何设计调制器电路参数。
关键字：Sigma Delta 调制器；精度；功耗；过采样技术；噪声整形技术
 
Design of sigma-delta modulator based on MATLAB
Abstract：Sigma Delta ADC (Analog to Digital Converter) is mainly composed of two parts: Sigma Delta modulator and digital filter. Compared with other types of ADCs, its advantages are higher conversion accuracy and lower power consumption. Among them, Sigma Delta Modulator has insensitivity to various non-ideal factors in process production, and it has lower requirements for analog circuit design, so it has been widely used in audio signal processing. In addition, the use of techniques such as oversampling and noise compression enables the Sigma-delta ADC to achieve high-precision analog-to-digital conversion.
Scholars comparing Sigma-delta ADCs with conventional analog-to-digital converters has found that sigma-delta ADCs not only have lower requirements for analog circuit performance and device matching, but are also easier to implement on-chip integration with other digital circuits. Therefore, the sigma-delta ADC has also been widely used along with the rapid development of the system-on-chip (SOC). This paper starts from the working principle of the sigma-delta modulator and discusses in detail the impact of non-ideal factors such as clock jitter, switching nonlinear resistance, and switching thermal noise on the performance of the modulator. Then, based on the above non-ideal factors, this paper deduces the time domain mathematical model of the modulator's performance. Based on this model, using simulink under MATLAB software, non-ideal construction of first-order and second-order sigma-delta modulators is performed. Using the method of simulation analysis, the module obtains the influence of non-ideal factors on the SNR of the modulator. Finally, this paper proposes the idea of global optimization design, that is, how to design the modulator circuit parameters in order to achieve the best performance of the modulator.
Key words：Sigma Delta Modulator; Precision; Power Consumption; Oversampling Technology; Noise Shaping Technology
 

第一章    绪论    5
1.1    研究背景与意义    5
1.2    国内外研究现状    5
1.3本文主要研究内容和结构    8
第二章    sigma-delta的基本原理    9
2.1奈奎斯特ADC    9
2.1.1采样过程原理    9
2.1.2量化过程原理    10
2.1.3 奈奎斯特 ADC 的主要类型介绍    11
2.2 过采样    12
2.3 噪音整形    12
2.4 ADC的性能指标    13
2.5本章小结    13
第三章    一阶Sigma Delta调制器设计    14
3.1一阶Sigma Delta 调制器时域分析    14
3.2一阶Sigma Delta 调制器频域分析    14
3.3一阶Sigma Delta 调制器系统模型图及仿真分析    15
3.3.1 一阶Sigma Delta 调制器系统模型图    15
3.3.2 一阶Sigma Delta 调制器的仿真分析    15
3.4 总结    17
第四章    二阶Sigma Delta调制器设计    18
4.1二阶Sigma Delta调制器频域分析    18
4.2二阶Sigma Delta 调制器系统模型图及仿真分析    18
4.2.1 二阶Sigma Delta 调制器系统模型图    18
4.2.2二阶Sigma Delta 调制器的仿真分析    19
4.3 总结    29
第五章    总结与展望    30
参考文献    31
致谢    32