RF and Digital Signal Processing for Software-Defined Radio

Chapter 9. ΔΣ Modulators for Data Conversion

In wireless communication, ΔΣ modulators are widely used as data converters to construct oversampled ADCs and DACs and they play an integral part in modern frequency synthesis. ΔΣ modulators operate at higher conversion or sampling rates than would be required by the Nyquist criterion. For this reason these types of data converters are known as oversampling converters. Despite their popularity, ΔΣ converters have yet to be adopted in SDR radios that employ IF sampling architecture. The obvious reasons are the required dynamic range and increased sampling rate required to support a multistandard multimode operation at IF. However, in wireless architectures that rely on quadrature demodulation such as ...