Study On The Platform Of Broadband Software Radio

This paper discusses the hardware system architecture of broadband software radio experiment platform, designs hardware circuit system , studies the basic theory of software radio deeply, establishes the mathematical model.The platform is made up of A/D ( AD6640 12bit 65 MSPS ) , orthogonality transform , digital filtering and DSP, etc. The platform can demodulate PCM-AM/FM/PM/ASK/FSK/PSK/QPSK, PCM-CDMA-PSK, PCM-QPSK signal.This paper makes out the sampling frequency of bandpass sampling theorem, reduces the data rate after the sampling of broadband software radio ( signal bandwidth is 20 MHz) and raises information processing speed. The major characteristic of the software radio experiment platform is a piece of large-scale field programmable logic gate array( FPGA) used to realize sequential eontrol,orthogonality transform and digital filtering ,which makes hardware structure simplely and has strong ability of reconstruction; The simple development and strong flexibility is a characteristic of software programming way to design hardware circuit. Additionally, this paper also gives the realization method of software radio demodulation, the result of emulational analysis, the voluntarily identification technology of signal modulation way and the synchronous technology in software radio .