Introduction to the Principle of Software-Defined Radio (SDR)
The core concept of Software-Defined Radio (SDR) is to build a universal hardware platform characterized by openness, standardization, and modularity. Various functions - such as operating frequency bands, modulation and demodulation types, data formats, encryption modes, and communication protocols - are implemented through software. Additionally, wideband analog-to-digital (A/D) and digital-to-analog (D/A) converters are placed as close to the antenna as possible. This approach enables the development of a new generation of highly flexible and open wireless communication systems.
Essentially, this platform can be controlled and reconfigured via software. By selecting different software modules, different functions can be achieved, and the software itself can be upgraded and updated. Similarly, the hardware can be continually updated and upgraded, much like a computer.
Since all functions of an SDR system are realized through software, adding new services or modulation methods simply requires integrating a new software module. Moreover, due to its ability to generate various modulation waveforms and communication protocols, it can communicate with legacy radio systems, significantly extending the lifecycle of existing equipment and reducing costs.
