A communication device where many components that were traditionally implemented in hardware (e.g., mixers, filters, amplifiers, modulators/demodulators, detectors) are instead implemented by means of software on a personal computer, embedded system, or field-programmable gate array. This architecture allows for flexible and adaptable communication systems capable of operating across a wide range of frequencies and modulation schemes. As an example, consider a device that can function as both a conventional FM radio receiver and a digital television receiver through the modification of its software.
This approach offers significant advantages, including reduced hardware costs, increased flexibility, and the ability to update or modify functionalities without physical component changes. This technology has revolutionized the field of wireless communications, enabling advancements in areas such as cognitive radio, spectrum sensing, and dynamic spectrum access. The evolution of signal processing capabilities and advancements in processing power have driven the increasing adoption of this technology across diverse applications, from amateur radio to military communications.
