Study And Realization On Multi-modulation Receiver Based On Software Radio

With the development of communication, the issuance of new standards andprotocols many problems arise from modulation schemes among differentcommunication systems existing in modem wireless communication systems. All kindof wireless communication system are limited within certain geographical areas, andthey are not compatible with each other. On the other hand, because the developmentcircle of many kinds of technical and digital processor and large scale integratedcircuit are shortened thedevelopment cost increase, and the upgrade cost does as well.In this case, the software radio technology arises at the historic moment, and becauseits benefits of flexibility, the modular structure, the strong versatility and so on thecharacteristics make it great useful in commercial and military field.Based on consulting extensively modem materials, this paper is written toresearch and develop the conception of software radio, Introduce the developmentcondition of software radio, elaborate in the software radio research content, the basicprinciple. United of its correlation technology and the components, and analyze thekey technologies. And then on the basis of architectural analysis of the commonreceiver, and combining with software radio characteristics, the structure design ofmulti-modulation receiver based on software radio has been given. Meantime, fromseveral aspects such as arithmetic speed, flexibility, we make a comparison withDSP,FPGA,ASIC, which are widely used in software radio, the proposal of the basisof alternative components are given.Because the signal of the multi-modulation receiver based on software radio is one ofAM,FM,4FSK, the principle of digital signal processing in the multi-modulationreceiver is as follows: according to amplitude of the received signal, AM signal isdistinguished with FM, 4FSK signals; comparing of the analog modulation anddigital modulation, FM is different from 4FSK. At the same time, the modulation ofAM,FM has been given: through directly modulation, realize the modulation of AM,FM is modulated by indirectly modulation. By extracting the quadrature and In-phasecomponent, realizes the demodulation of AM and FM. 4FSK signal is to have to demodulate by the frequency selection. Using matlab and thesystemview software to simulate the algorithm, the experimental report is given,finally...