∑-Δ ADC在软件无线电移动终端中的应用

Application of ∑-Δ ADC in Software Radio Mobile Terminal

模数转换器是基于软件无线电的多模移动终端中的关键器件。∑-Δ模数转换器(∑-ΔADC)是利用∑-Δ调制技术和数字滤波技术实现的一种高精度模数转换器,主要由∑-Δ调制器和数字降采样滤波器构成。简要描述了移动通信信号特征,对闪烁型模数转换器(Flash-ADC)和∑-Δ模数转换器的性能进行了详细分析与比较,指出∑-Δ模数转换器可以更好地满足多模移动终端中对大动态范围A/D转换的要求。

Analog-to-digital converter is a key component in multi-mode mobile communication terminals based on software radio concept.Sigma-Delta（∑-Δ） ADC is a kind of high resolution ADC which employs ∑-Δ modulation and digital filtering techniques. It is composed of a modulator and a digital de-sampling filter. The article briefly describes the characteristics of mobile communication signal, and analyzes the performance of ∑-Δ converter compared with Flash-ADC. It is shown that ∑-Δconverter can better meet the requirement of analog-digital conversion in multi-mode mobile communication terminals.