As communications technology continues its rapid transition from analog to digital, more functions of contemporary radio systems are implemented in software - leading toward the software radio. A software radio is a radio whose channel modulation waveforms are defined in software. 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 receiver, similarly, employs a wideband Analog to Digital Converter (ADC) that captures all of the channels of the software radio node. The receiver then extracts, downconverts and demodulates the channel waveform using software on a general purpose processor. Software radios employ a combination of techniques that include multi-band antennas and RF conversion; wideband ADC and Digital to Analog conversion (DAC); and the implementation of IF, baseband and bitstream processing functions in general purpose programmable processors. The resulting software-defined radio (or "software radio") in part extends the evolution of programmable hardware, increasing flexibility via increased programmability. And in part it represents an ideal that may never be fully implemented but that nevertheless simplifies and illuminates tradeoffs in radio architectures that seek to balance standards compatibility, technology insertion and the compelling economics of today's highly competitive marketplaces. Interested? Click here ...