A software-defined radio (SDR) system is like a computer with a radio frequency (RF) front end. Functions that were previously hard-wired, such as modulation/demodulation and encoding/decoding, are not programmable. An advantage of SDR is the potential to reduce life-cycle costs, compared with conventional radios. If additional capability is needed once the radio had been shipped, that capability can in most cases be added via software, thus decreasing the need for changeout of physical hardware. SDR has seen implementation among ground-based radio systems for combat troops and is beginning to be employed in military avionics.
- SDR generate a lot of heat, and the availability of cooling on an aircraft is limited. Lessons learned from recent incidents involving high-energy-density batteries aboard aircraft must be brought to bear on SDR implementations.
- SDR avionics may require dedicated network monitoring software to prevent malware of highjacking or disabling of the avionics by unauthorized personnel.
- Controlled information available on the SDR network could be leaked if the network was tapped into. Careful design of the bandwidth of the network “pipes,” the accessibility of information among multiple nodes, and the kind of information carried within the network will require careful, upfront design work.
- SDR changes the role of systems suppliers. Providers of the hardware cards must build them to accommodate software written by others.
- Challenges in technology certification.
- SDR systems may have unique human-systems interaction considerations. The “what’s-it-doing-now” phenomenon? Will there be issues of interface design such as use of touch screens in a realistic flight environment (turbulence, vibration, etc.).