Multi-Mode Receiver Design for Wireless Terminals

The ongoing evolution from 2G to 3G and beyond confronts the cellular market with the challenges of a broad diversity of communication standards. Furthermore, increasing levels of integration with minimum external component count, advances in semiconductor process technology, and the requirement for multi-mode operation are pivotal demands of the RF-IC manufactures to achieve fast design cycles and low product cost. As a result, reconfiguration of the wireless terminal has become the key issue in the design of wireless terminals. This paper discusses the requirements for multi-mode reconfigurable wireless receivers with focus put onto mixed-signal and digital enhancements to traditional analog front-end designs. The flexibility a digital-front-end (DFE) introduces is studied with respect to the main cellular communication standards (GSM/EDGE, CDMA2000, W-CDMA/HSDPA, and LTE) and satellite navigation systems (GPS, Galileo), with considerations of impacts on the capability of an implementation of a software-defined-radio (SDR).