The transmission of live surveillance video beyond line of sight from Unmanned Aerial Systems (UAS) requires an onboard satellite transmission system.
Although larger UAS such as the IAI Heron or MQ-1 Predator can carry a large-size VSAT system (using Ku-, Ka-, or X-bands through military or commercial providers), most UAS do not have room for a 60 cm antenna or enough power to carry up to 20 kilograms of equipment.
Austrian company Scotty Group has developed a smaller L-Band system that can use the Inmarsat or Thuraya networks (Thuraya will be offering airborne systems in mid-2017).
“L-Band, although lower in bandwidth, can still offer live high quality video through the use of onboard compression and our system can compress video so well that it is both in real time and at HD quality,” Scotty Group director Manfred Schering said. “Furthermore, depending on how much information needs to be exchanged, there are many hardware configurations to choose from.”
Graham Elliott, general manager at Maser Defence, which locally supplies the Scotty system and others, said Cobham Ltd was also offering similar solutions.
They offer a system weighing six kilograms using an antenna with a footprint of only three square centimetres or weighing ten kilograms with an antenna kit the size of a soccer ball,” he said. “The larger system is good for transmitting high quality video, the smaller one can offer HD stills and lower quality live video.”
All of the L-Band systems are lighter, smaller, and less expensive than VSAT and they perform perfectly in adverse weather as rain does not interfere with the lower frequency L-band.
According to Elliott, another advantage of L-Band is that traffic is routed through the Internet.
“By adding AES 256 bit encryption (which Scotty offers), secure video can therefore be received anywhere in the world from an aircraft above any remote location.”