The mobile wireless communication industry has seen explosive growth inthe last decade of the twentieth century. Migration to high frequencies and widerbands for radio access allowed increased capacity for more users. This coupledwith increaseddemand for high bandwidth wirelesscommunication has resultedin rapid commercial development of wirelessdevices.This rapid developmenthas generated cost effective solutions and wide spread usage among the public(405 million cell phones were sold in 2002) [1]. Higher levels of integrationwith technological advancements in CMOS have allowed the implementation ofcomplexdigital modulation schemes with reasonablepower consumption‚cost‚and size for higher data rates. This‚ in turn‚ has paved roads for today’s mod-ern mobile wireless systems (second and third generations: 2G and 3G) withhigh data rates at reasonable cost. This chapter outlines a scenario for fourthgeneration (4G) wireless systems and discusses the challenges for designingphase-lock loops (PLLs) and voltage-controlled oscillators (VCOs) needed for4G. Then‚ the chapter discusses the objectives and outlines the organization ofthe book.
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