设计了一个在信号带宽200kHz下,动态范围超过90dB的5阶单环单比特Σ-Δ调制器,该调制器能够很好的应用于中低频GSM接收机中。为了降低电路的复杂程度,提高系统抗噪性,该调制器采用了具有前反馈和负反馈分支的Σ-Δ结构。Matlab仿真结果...设计了一个在信号带宽200kHz下,动态范围超过90dB的5阶单环单比特Σ-Δ调制器,该调制器能够很好的应用于中低频GSM接收机中。为了降低电路的复杂程度,提高系统抗噪性,该调制器采用了具有前反馈和负反馈分支的Σ-Δ结构。Matlab仿真结果显示,在1.8V工作电压、0.18μ m CMOS工艺条件下,采样频率为21M Hz,SNDR为93.9dB,功耗为9.5mW,该系统具有较高实用价值。展开更多
The sinusoid curve fit is widely applied in the evaluation of digitized measurement equipment, such as data acquisition system, digital storage oscilloscope, waveform recorder and A/D converter,etc. Because of the di...The sinusoid curve fit is widely applied in the evaluation of digitized measurement equipment, such as data acquisition system, digital storage oscilloscope, waveform recorder and A/D converter,etc. Because of the distortion and noise of sinusoid signal generator, the digitizing and the non linearity errors in measurement, it is impossible to avoid the distortion and the noise in sinusoid sampling series. The distortion and the noise limit the accuracy of curve fit results. Therefore, it is desirable to find a filter that can filter out both distortion and noise of the sinusoid sampling series, and in the meantime, the filter doesn′t influence the amplitude, the frequency, the phase and DC bias of fitting curve of the sine wave. And then, the uncertainty of fitting parameter can be reduced. This filter is designed and realized. Its realization in time domain is described and its transfer function in frequency domain is presented.展开更多
文摘设计了一个在信号带宽200kHz下,动态范围超过90dB的5阶单环单比特Σ-Δ调制器,该调制器能够很好的应用于中低频GSM接收机中。为了降低电路的复杂程度,提高系统抗噪性,该调制器采用了具有前反馈和负反馈分支的Σ-Δ结构。Matlab仿真结果显示,在1.8V工作电压、0.18μ m CMOS工艺条件下,采样频率为21M Hz,SNDR为93.9dB,功耗为9.5mW,该系统具有较高实用价值。
文摘The sinusoid curve fit is widely applied in the evaluation of digitized measurement equipment, such as data acquisition system, digital storage oscilloscope, waveform recorder and A/D converter,etc. Because of the distortion and noise of sinusoid signal generator, the digitizing and the non linearity errors in measurement, it is impossible to avoid the distortion and the noise in sinusoid sampling series. The distortion and the noise limit the accuracy of curve fit results. Therefore, it is desirable to find a filter that can filter out both distortion and noise of the sinusoid sampling series, and in the meantime, the filter doesn′t influence the amplitude, the frequency, the phase and DC bias of fitting curve of the sine wave. And then, the uncertainty of fitting parameter can be reduced. This filter is designed and realized. Its realization in time domain is described and its transfer function in frequency domain is presented.
