New Budget Darling May Be Directed-Energy

After decades of promises, directed-energy weapons appear headed for near-term operational use and may be led there by electronic attack programs under development for the military.

The lightning rod for rapid fielding of directed-energy devices and advanced sensors will be the U.S. services’ next-generation jammers, which will likely feature active, electronically scanned arrays and high-power microwave (HPM) capabilities. In Pentagon discussions, HPM is now being called “anti-electronics weaponry.” Power surges created by pulses of HPM can damage or destroy electronic components and addle or erase computer memories. How HPM, high-power lasers and jammers might be integrated is still a work in progress. That directed energy and its associated technologies (such as intelligence gathering, surveillance, cyberattack and electronic warfare) may be focused and accelerated by some of the new electronic attack programs was suggested by David Honey. He is chief of policy and oversight for the Defense Department’s science and technology programs.

“HPM is under-appreciated and an area of great interest that requires robust investment,” Honey says. These non­kinetic weapons are needed to function as alternatives and adjuncts to explosive devices; however, he cautions that development of small, energetic, power sources and unique-waveform generation will require a “lot of work” in areas such as compact pulse power, solid-state power sources and advanced antenna design. But once the technology is operational, it will fit into “a number of key operational areas,” Honey says.

The HPM “e-bomb” will be fielded “later this decade,” as researchers learn to control the effects with directionality of the energy beam through antenna design. Honey predicts that the mobile, high-energy laser will be operational “in the short future.”

Variations of technologies used in the commercial world have been identified as projects that could prosper over the next decades in the defense world. They include camouflaged, foldable, lightweight and highly portable versions of electronically scanned array antennas. Also under discussion is a parachute canopy version of an advanced antenna that could be dropped from aircraft, says R. Alan Kehs, a former chief of the U.S. Army Research Laboratory’s directed-energy branch. The canopy serves a double function: It is a concave antenna that focuses HPM pulses at targets—probably radars or surface-to-air missiles—as it falls. It also serves as a parachute to carry a large power source.

Concerning the “novel uses and insights” of lasers, interest is focused on “the different effects [produced by lasers using] pulse format and continuous wave,” says Mark Neice, director of the High-Energy Laser Joint Technology Office. “Can we get the right [amount of unwanted electrical] coupling into advanced seekers to generate the desired effect?” he asks.

The U.S. Air Force in particular is worried about countering the capabilities of advanced anti-aircraft missiles against transport aircraft.

“Since infrared countermeasures are already integrated into many large airlifters, increasing the power of the laser source—which buys you longer range—should be relatively simple,” Neice says.

A problem area remains in how to protect aircraft that do not already have a protective IR system on which to build. Next-generation programs in this discipline may provide the answer.

“If you have a radar capability on those [vulnerable] platforms, how can we channel that?” he says. “If you can figure out a way to gain the same capability—from broad-spectrum tracking to a precision engagement [capability]—without adding the complexity of a handover to an alternate optical system, you gain tremendous benefit” in speed and precision for combating enemy anti-aircraft systems.

An associated phenomenon that the U.S. sees as an offensive boon and a defensive nightmare is the ever-decreasing amounts of electricity that it takes to power advanced electronics.

“It takes much less energy to destroy [electronic] devices now” because they operate “closer to the edge of upset,” Kehs says. “As you move down to the sub-volt [environment], it is easier to upset [a device].”

Upsetting a device is the preferred approach because it requires rebooting the system—which provides a window for attack—while burnout or destruction requires 2-3 orders of magnitude more power. Moreover, to gain approval for the launch of high-power attacks, it is necessary to understand how associated systems would be affected.