The equipment needed for long-range high-bandwidth wi-fi is often unavailable to troops in the field.

Engineers hope this will be remedied with airborne wi-fi hotspots that can remain close to isolated troops.

Getting access to a secure, stable and fast internet connection might become easier for remote US troops if the Defense Advanced Research Projects Agency's (Darpa) latest wi-fi hotspot programme successfully launches.

Engineers at Darpa recently completed the first of three test phases, which saw the development of key technologies to be integrated into a complete system.

"We're pleased with the technical achievements we've seen so far in steerable millimetre-wave antennas and millimetre-wave amplifier technology," said Dick Ridgway, Darpa programme manager.

"These successes - and the novel networking approaches needed to maintain these high-capacity links - are key to providing forward deployed units with the same high-capacity connectivity we all enjoy over our 4G cell-phone networks."

The accomplishments of the initial phases include: smaller, steerable antennas; signal boosters; increased power efficiency and a light pod to carry the device on the unmanned aerial vehicle (UAV) itself. The network is said to be potentially capable of a 1 gigabit per-second (Gb/s) capacity.