The Pentagon is planning to turn old drones into wi-fi hotspots.

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.

The move is similar to Facebook's initiative to bring the world online with blanket wi-fi, but some critics fear the drones will compromise security.

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, which is as fast as Google Fiber's.

Darpa's move is reminiscent of Mark Zuckerberg's recent announcement that he wishes to connect the two-thirds of the world that has no net access, using drones, satellites and lasers - albeit for different reasons.

However, Chris Cole editor of Drone Wars UK, has criticised Darpa, warning that the drones will ultimately provide less security.

"Again we see drones being used to enable the projection of lethal military force in remote locations.

"Regardless of whether drones are delivering weapons or wi-fi it seems that the growing use of unmanned systems simply means more war and less overall security in the future."