Cdma2000 Base Station Transceiver Rf Front-end Analysis And Design,

Wireless communication plays an important role in modern communication system. It gets a rapid development from 1980s.The third generation wireless communication network has been used worldwide.The standards of 3^rd generation are CDMA2000, WCDMA and TD-SCDMA.They all base on CDMA(Code Division Multiple Access) technology.CDMA2000 is totally compatible with IS-95.So CDMA2000 has the biggest competitive advantage.The transceiver is one of the most important parts in base station system.The performance of the transceiver decides the air interface specifications directly.The key item of this work is design excellent transceiver RF front end according to recommended minimum performance standards by 3GPP2.We give an analysis of balanced low noise amplifier(LNA) which has good voltage standing wave ratio (VSWR) performance,higher linearity and good stability.A mathematic model of balanced LNA has been setup and an analysis of gain,noise figure(NF) and VSWR based on it is presented.According to analysis in time domain and simulation in advance deign system(ADS),the unbalance of gain,NF and VSWR will affect the performance of the balanced LNA module.It gets a zero reflection on condition that its two branches totally balanced.The primary work of this paper includes theory analysis,simulation,circuit design, PCB layout and system testing.The content architecture of this paper is shown as follows:1.Analysis of key devices of the transceiver,such as LNA,LO(local oscillator), ADC,sampling clock and so on.The relationship of specifications between key devices and CDMA2000 system are proposed too.2.Analysis and design of balanced LNA and LO module.A detailed analysis, simulation and design steps of balanced LNA and LO are proposed.3.Analysis and design of tranceiver RF chains.The specifications of transceiver meet the standards of 3GPP2,such as output power,EVM,frequency stability,emission spurious,ACPR,sensitivity,and single-tone desensization.The design methods and chain structure are proposed.4.The testing methods and results of LNA,LO,and transceiver are introduced in chapter 5.Conclusions are also proposed in this chapter.Acoording to precise theory analysis,simulation and design,we design a transceiver which has excellent performance,and can be used in all CDMA band classes. The testing results indicate the design is coincident to the standars of 3GPP2.