Hardware Design And Realization Of Digital IF Processing Platform Based On Software Radio

Software radio(SR) has caused serious concerns ,since it newly emerged ,because it is a new communication technology to solve the problem of intercommunication and incapatibility between different communicatin systems,depending on its digitalization,flexibility and opening. It is generally accepted that SR is the third technical revolution following from fixed to mobile communication and from analog to digital communication,as well as the development orientation of radio communication in the future. SR has a bright future for application in military,civil and personal communication.Therefore,it is important and meaningful to build a general and open hardware platform for SR. However,restricted by the performance of hardware,such as the poor processing speed of A/D,D/A convertor and DSP, most current software radio systems have to adopt middle course ,ie, IF digital software radio,which converts RF signal to IF signal by using digital convertor,and then completes the baseband signal processing.Although IF digital software radio differs from the ideal software radio,it is an available solution with less performance requirements for the semiconductor components.A digital IF processing hardware platform is designed and realized for SR following IF digital SR architecture,in this paper whose contribution includes studying IF digital SR,designing total solution,choicing chips and components,designing circuit schematics and PCB,welding electrical components ,debugging hardware platform and editing programs to test hardware modules.First,in this paper, an overview of SR is given and its theory is introduced in detail,especially IF digital technology including signal sampling and multi-rate signal processing.Meanwhile,a process of derivation for formulas and important conclutions is presented.Secondly,design and realization of hardware platform is completed.After comparing three current main-stream hardware solutions for SR including GPP,FPGA and DSP, DSP+FPGA solution is adopted .The whole hardware platform is divided into two parts: DSP baseband board and FPGA IF board.On DSP baseband board,TMS320DM6446 based on Davinci technology from TI is adopted as the core DSP chip,in which an ARM core and a DSP core are intergrated.While on the FPGA IF board,EP2C20Q240C8 in the family of Cyclone II FPGA from Altera is used as the core chip.In this design , Protel 99SE is used as the tool to design circuit schematics and PCB.Finally,hardware platform debugging is completed,and the conclution and prospect are given.During debugging, equipments are used to test hardware circuit,and programs are edited to test hardware modules.After debugging , pictures of hardware platform are given as reference.