Software Radio
Abstract
Software radio is the art and science of building radios using software.Given the constraints of todays technology,there is still some hardware involved,but the idea is to get the software as close to the antenna as possible.Ultimately we are turning hardware problems into software problems. A software radio is a radio whose channel modulation waveforms are defined in sofware.The fundamental characteristic is that software defines the transmitted waveforms and software demodulates the recieved waveforms. That is waveforms are generated as sampled digital signals,converted from digital to analog via a wideband DAC and then possibly upconverted from IF to RF.The reciever,similarly,employa a wideband ADC that captures all of the chnnels of the software radio node.The reciever then extracts,downconverts and demodulates the channel waveform using software on a general purpose computer.