基于Simulink的Sigma-DeltaA/D转换器调制器系统建模

Simulink System Model of Sigma-Delta Analog-Digital Converter Modulator

基于Sigma-Delta模数转换器结构,采用Simulink仿真工具提出了过采样Sigma-Delta调制器系统建模方法。结合调制器结构参数和电路噪声参数,建立了二阶低通型和二阶带通型过采样Sigma-Delta模数转换器调制器的非理想系统模型,并对调制器的功率谱密度图和信噪比进行仿真,验证了建模方法的正确性。

Based on the structure of Sigma-Delta analog-to-digital converter, a system modeling method for over-sampling sigma-delta modulator was proposed by Simulink which is a simulation tool. Considering the modulator structure and the noise of circuits, the non-ideal system model for second-order low-pass and band-pass sigma-delta modulator were founded. For verifying the modeling method, the PSD and SNR of the modulators models was simulated. The proposed modeling method for Sigma-Delta modulator is significant for Sigma-Delta analog-to-digital converter design.