What is a software defined radio?
A software defined radio is one where the RF signal is converted to a digital bit stream and all of the modulation and demodulation of the signal is done with digital signal processors (DSPs). An SDR performs significant amounts of signal processing in a general purpose computer, or a reconfigurable piece of digital electronics. The goal of this design is to produce a radio that can receive and transmit a new form of radio protocol just by running new software. The SDR concept which led to the development of the first SDR experimenter’s kit for ham radio was first described by FlexRadio Systems CEO Gerald Youngblood (K5SDR) in QEX during the summer of 2002. Gerald’s four part article on the concepts and techniques used to develop the worlds first SDR for ham radio operators is still the quintessential primer on SDRs for ham operators. • Part 1 introduces DSP and how it is applied to SDRs along with describing a transceiver architecture. • Part 2 describes the initial software engineeri
