Alternative wideband front-end architectures for multi-standard software radios

One of the recent increasing demands from wireless communications to IC designers is to design extremely flexible receivers that can support multiple standards. This paper addresses the design issues of front-end architectures for multi-standard wireless transceivers. It also presents two sampling front-ends known as direct subsampling and IF subsampling for multi-standard radios. These front-ends are well suited for software radios due to the limited dynamic range of ADC in today´s technology. They differ from conventional types by providing low power and high integration, and eliminating some existing problems such as DC offset, DC voltage drifts, and 1/f noise.