Readily available, first-rate wireless links are essential for building and running safe UAV systems. David Weight, principal electronics engineer at Waittcircuit, recently shared his thoughts on the importance developing and maintaining high-quality wireless links as the UAV industry expands.
One of the major challenges that is emerging in the UAV industry is maintaining wireless links with high availability. As UAVs start to share airspace with other vehicles, we need to demonstrate that a control link can be maintained in a wide variety of environments, including interference and non-line of sight. We are starting to see software defined radio used to build radios which are frequency agile and capable of using multiple modulation techniques. For example, being able to use direct links in open spaces where these are most effective, but being able to change to 4G type signals when entering more built-up areas as these areas can pose issues for direct links, but have good coverage for existing commercial telecoms. Being able to change the frequency and modulation also means that, where interference or poor signal paths are found, frequencies can be changed to avoid interference, or in extreme cases, be reduced to lower bands which allow control links to be maintained. This may mean that not all the data can be transmitted back, but it will keep the link alive and continue to transmit sufficient information to allow the pilot to control the UAV safely.