The Defense Advanced Research Projects Agency (DARPA) plans to refurbish a fleet of obsolete unmanned aerial vehicles or aerial drones to help the US military carry out operations in remote locations without Internet connectivity.

As part of its new "Mobile Hotspots Program," DARPA will retrofit a fleet of aging "RQ-7 Shadow" drones that were once deployed for battlefield missions by the US military in Iraq. The RQ-7 Shadow was used by the US Army and Marine Corps for reconnaissance, surveillance, target acquisition and battle damage assessment.

It is launched from a trailer-mounted pneumatic catapult and recovered with the aid of an arresting gear similar to that on a jet that lands on an aircraft carrier. Its electro-optical/infrared camera relays video in real time via a C-band line-of-sight data link to the ground control station.

DARPA's hotspot program aims to provide a 1Gbps communications backbone to US military units deployed in the field. Each drone will be equipped with a lightweight, low-power pod holding low-noise amplifiers to establish a secure connection from ground stations without requiring large antennas.

DARPA says this equipment can boost signals while minimizing background noise. The drones can fly for nine-hours and will provide continual coverage as needed.

Dick Ridgway, DARPA program manager, said missions in remote, forward operating locations often suffer from a lack of connectivity to tactical operation centers and access to valuable intelligence surveillance and reconnaissance data.

"The assets needed for long-range, high-bandwidth communications capabilities are often unavailable. DARPA's mobile hotspots program aims to help overcome this challenge by developing a reliable, on-demand capability for establishing long-range, high-capacity reachback that is organic to tactical units," he said.

Ridgway noted that the Phase 1 field tests were very successful. He said the pointing, acquisition and tracking algorithms were very fast, with some showing millimeter-wave link alignment in just a few seconds.

This will enable the formation of a high-capacity backhaul network between aerial and ground platforms.