Directed-energy weapons are among a handful of maturing disruptive or asymmetric technologies that could confer game-changing technological advantages both as a superior defensive capability and as an effective electronic attack option. US Navy’s 30-kilowatt Laser Weapon System (LaWS) on USS Ponce is the first laser weapon to have attained Initial Operating Capability (IOC) by virtue of being deployed in a combat theater. The US Air Force is pursuing laser weapons systems (LWS) along with high powered electromagnetics (HPEM) to enable operations in a possible future battlespace involving a technologically advanced adversary with the ability to prevent access to—or deny our ability to operate in—a given area. There is also increased interest in defending against Unmanned Aerial Systems (UAS) and hypersonic weapons.
US is not alone in working to perfecting laser weapons. Russia, China and other countries also have similar programs. US Navy report also confirmed Russia’s plans to develop laser weapons, “Russia plans to develop a high-energy laser weapon with anti-satellite and cruise missile defense capability, and is working on the weaponization of its laser energy systems.”
Directed Energy Weapons (DEW) are an umbrella term covering systems that emits highly focused energy / atomic or subatomic particles and transfers that energy to incapacitate, damage, disable or destroy enemy equipment, facilities and/or personnel. The energy can come in various forms: Electromagnetic radiation, including radio frequency, microwave, lasers and masers, Particles with mass, in particle-beam weapons, Sound, in sonic weapons.
Directed energy has the potential to yield cost effective weapons that can deliver precise, scalable effects – and at long ranges – with a large magazine capacity. Potential applications of this technology include anti-personnel weapon systems, potential missile defense system, and the disabling of lightly armored vehicles such as cars, drones, watercraft, and electronic devices such as mobile phones.
The use of lasers by military and security agencies has been rapidly growing; they have also become easier to buy on the internet. Laser directed energy weapons are being developed to neutralize rockets, UAVs and missiles. “It is anticipated that directed energy weapons will pose a radical and unprecedented threat to future military assets by the 2020-2025 timeframe. According to an October 2016 report by Washington-based analysts MarketsandMarkets, the global market for DEWs is projected to grow to $24.45 billion by 2021, at a compound annual growth rate of 28.9 per cent. The main factor driving this impressive growth is the increasing demand for effective defence against missiles and UAVs.
Therefore Militaries are preparing to face directed energy weapons, in future battles. Military is increasingly looking for technologies for protection of equipment, facilities and/or personnel. Australian Army has introduced an enhanced ballistic laser ocular protection system (BLOPS) as part of the new soldier combat ensemble that provides ballistic, environmental and laser protection to soldiers. However they provide protection against limited spectrum of common lasers (laser lenses).
In order to prepare for this threat, the military must be prepared with a set of effective counters and countermeasures to use against these weapons,” Says Beth Clement, Program Manager CDEW program.
Directed energy atmospheric lens could revolutionise future battlefields
Within the next fifty years, scientists at BAE Systems believe that battlefield commanders could deploy a new type of directed energy laser and lens system, called a Laser Developed Atmospheric Lens which is capable of enhancing commanders’ ability to observe adversaries’ activities over much greater distances than existing sensors.
At the same time, the lens could be used as a form of ‘deflector shield’ to protect friendly aircraft, ships, land vehicles and troops from incoming attacks by high power laser weapons that could also become a reality in the same time period.
The Laser Developed Atmospheric Lens (LDAL) concept, developed by technologists at the Company’s military aircraft facility in Warton, Lancashire, works by simulating naturally occurring phenomena and temporarily – and reversibly – changes the Earth’s atmosphere into lens-like structures to magnify or change the path of electromagnetic waves such as light and radio signals.
LDAL is a complex and innovative concept that copies two existing effects in nature; the reflective properties of the ionosphere and desert mirages. Ionosphere is high altitude layer in atmosphere which can bounce low frequency signals allowing them to travel very long distances through the air and over the Earth’s surface. The desert mirage provides the illusion of a distant lake in the hot desert. This is because the light from the blue sky is ‘bent’ or refracted by the hot air near the surface and into the vision of the person looking into the distance.
LDAL simulates both of these effects by using a high pulsed power laser system and exploiting a physics phenomena called the ‘Kerr Effect’ to temporarily ionise or heat a small region of atmosphere in a structured way. Mirrors, glass lenses, and structures like Fresnel zone plates could all be replicated using the atmosphere, allowing the physics of refraction, reflection, and diffraction to be exploited.
“Working with some of the best scientific minds in the UK, we’re able to incorporate emerging and disruptive technologies and evolve the landscape of potential military technologies in ways that, five or ten years ago, many would never have dreamed possible,” said Professor Nick Colosimo, BAE Systems’ Futurist and Technologist.
One of way to protect against lasers is to cover the targets like drones etc with mirrors. Ryan Hoffman, Counter-Directed Energy program manager, says that mirrors protect well against low-power lasers. “However, reflective surfaces are not 100 percent reflective,” he says. “The small amount of laser energy that’s absorbed will heat the mirror and cause damage.”
To avoid this, drones will require a superior mirror. Dielectric or Bragg mirrors are composed of many layers of dielectric material (a type of insulator), with precise spacing between each one. By adjusting the layers, engineers can create a mirror with a reflectivity of up to 99.99 percent. That reflectivity, however, only works for a specific, narrow range of wavelengths.
“Protecting against all wavelengths would be ideal, but difficult,” Hoffman says.
Instead of layers of dielectric mirrors, the same effect may also be be produced with specific nanocoatings. Reportedly US Air Force has funded research into making such coatings from engineered nanoparticles.
Apart from daunting technical challenges, lasers can only be used in certain weather conditions. In turbulent atmospheric conditions, like dust and humidity, the laser must propagate efficiently and stay accurately focused on the target. Moreover, they can’t, for example, be used in cloudy and humid conditions.
Subrata Ghoshroy of MIT’s Science, Technology and Global Security Working Group wrote in the Bulletin of Atomic Scientists: Any weapon that relies upon light traveling through the atmosphere runs into the problems of dust, humidity, and fog—features which absorb and scatter the laser energy. In addition, atmospheric distortions such as turbulence can deflect a beam of light. And at the same time that the photons in a laser’s beam must overcome all of these obstacles, they must also stay focused in a tight column and keep advancing forward without diminishing in power. Meanwhile, the user of the laser weapon must account for the movement of the target, the movement of the firing platform, and any decoys, dummies, or multiple war warheads that the enemy throws up.
Dmitry Litovkin, writes for RIR “For this reason the LaWS were tested in the Persian Gulf, which usually has sunny weather, and not in Alaska with its fog, rain and snow.” Sea air is full of moisture, which can weaken and distort the laser beam. Higher altitude air is clearer, but airborne lasers still require sophisticated corrective optics to stay focused on their target.
China plans to defeat American lasers with smoke
According to an article published on China.com, a site that appears to be ultimately owned by the Chinese government, the People’s Liberation Army is looking at using smokescreens to protect against lasers. So China’s army is looking into quick ways to put smoke up where they need it. From Popular Mechanics:
The PLA is experimenting with creating smoke in two ways: creating sulfur trioxide smoke through burning materials (spraying oil on a hot diesel engine is one way to do it) or creating an oily fog. The PLA Chemical Corps plans to use a new multiple canister launcher (pictured) to rapidly lay down protective smoke screens for nearby friendly forces.
If smoke beats lasers, and for a few years it certainly might, there’s an even older force that can completely undermine smoke: wind. As futuristic as modern war is, weather still gets a says Kelsey D. Atherton.
Smog over Beijing, Moscow may inhibit laser weapons, Chinese official claims
According to Navy Rear Admiral Zhang Zhoazong, the smog in Beijing and other large Chinese cities contains “tiny metallic particles” that would make it difficult for American lasers to penetrate, should a conflict between the powers ever emerge.
“Under conditions where there is no smog, a laser weapon can fire [at a range of] 10 kilometers,” Zhang said on state-run TV. “When there’s smog, it’s only 1 kilometer. What’s the point of making this kind of weapon?”
Zhang explained that he wasn’t endorsing pollution, merely explaining its effects. “I just stated a laser weapon’s weakness,” he said. “I don’t support smog.”
It sounds absurd, but — incredibly enough — Zhang could be right. The drops of polluted water in smog actually could deter laser weapons, said McCall Paxon, a former Army Ranger who is now an analyst with Rook Security
“For now,” notes Kozyulin, “the laser system’s numerous tests are nothing but the study of the technology for the future.
ONR’s Counter Directed Energy Weapons Program
ONR’s Counter-Directed Energy Weapons (CDEW) Program explores innovative research and solutions aimed at delivering a new means for adapting to, defending against, and negating the effects of hostile high-energy lasers, high-power microwaves, and other directed energy weapons in the maritime domain.
The Office of Naval Research (ONR), together with the Naval Postgraduate School, the U.S. Naval Academy, the Naval Research Laboratory, and naval air, space and surface warfare centers are investigating basic research topics related to countering the threats that come from directed energy weapons systems, such as high-energy lasers or highpower microwaves.
ONR is considering all options including reflective coatings, ablative materials, and thermal transport to mitigate against or delay laser’s harmful effects. The coating of Ablative materials can absorb laser energy and vaprorise itself while protecting the target beneath it. The thermal transport delay tries to delay laser harmful effects by covering the target by layers of insulating materials and air gaps.
ONR has started basic research efforts with potential airborne, surface, ground and underwater applications that would provide operational effectiveness against various known and projected weapon systems. In the coming years, efforts will continue to expand in the commercial, university, and academic environments to broaden the scope of CDEW research topics and understanding.
Funding has already been provided to examine innovative technologies, techniques and tactics. This research examines both material and nonmaterial solutions, and their implications when related to the nullification of various directed energy weapon concepts.
The basic research tenet of CDEW strives to understand how energy transmission and conversion inefficiencies can be exploited as a countering technique. Lasers and high-power microwaves transmit energy through the electromagnetic spectrum, and the energy being deposited in the illuminated object causes it to heat up, melt, or burn. CDEW efforts possess the potential to dissipate, defocus, or reflect energy, resulting in reduced damage to the target.
Current studies include the modeling of effects to address concerns for human safety as well as total systems integration with existing naval platforms.
Specifically, high-energy lasers can be used in maritime operations under various ship-to ship engagements, but their utility may be limited due to atmospheric conditions. Typical ranges for most lasers are known to have their effectiveness limited due to high-clutter environments and the optical effects of water in the air caused by sea spray. ONR is pursuing a new understanding that will address the complexities of fighting at sea in an already complex naval warfighting construct.
Some aspects of the CDEW research can have potential civilian applications, such as laser eye protection.
Research Challenges and Opportunities include Laser and high-power microwave-hardened materials, Directed energy weapons modeling and simulation, Atmospheric and turbulence-induced scattering of lasers, Chaos theory and predictive methods of electronic circuit failure
Aerospace Systems Design Laboratory’s Counter Directed Energy Weapons
“In order to evaluate and recommend counters and countermeasures against DEWs, the weapons themselves must first be understood.” The CDEW team thoroughly researched different types of directed energy weapons, the physics of how they work, and proposed capabilities for the given timeframe. “Various scenarios were considered to explore the numerous engagement possibilities.
Once the team had a complete understanding of the threats, counters and countermeasures were researched. These included physical devices and material coatings, as well as operational procedures, such as evasive maneuvering.” Fully evaluating the effects of counters and countermeasures (CCMs) required consideration of weapon and CCM properties, asset behavior, and the fighting environment.
“A modeling and simulation environment was created based on HELEEOS and an in-house radio frequency propagation model. To model laser weapons and their effects, the team used HELEEOS, an Air Force laser propagation code. HELEEOS allows for end-to-end calculation of any figures of merit needed in this project regarding lasers. To model radio frequency weapons, an in-house tool was developed to perform direct calculation of beam attenuation from first principles and empirical trends” This environment allowed for evaluation of directed energy threats, ranking of counter and countermeasure packages for given scenarios and direct comparisons of counters and countermeasures in real time.”
These counters and countermeasures took advantage of the threat’s limitations or amplified non-ideal conditions that would negatively affect the weapon’s performance. In creating this set of counters and countermeasures, it was assumed that the asset being protected would have the capability of active threat assessment. This meant that it would be able to detect the enemy attack, and classify the threat based on power level or type of weapon.
The list of countermeasures was broken down, based on properties, into three sub-groups: materials, hardening, and obscurants. The materials were coatings or layers that could be applied to the surface of an asset that would reflect the harmful electromagnetic waves. This would offer thermal protection by ultimately reducing the amount of power that is absorbed by the asset. Hardening countermeasures mitigate the effect of external electromagnetic fields, by either reducing the number of conductive paths or reducing the probability of electromagnetic coupling. This would allow for uninterrupted communication for assets during radio frequency attacks.
Obscurants use water or smoke to create unfavorable atmospheric conditions for laser and radio frequency weapons. The remaining counters were defined as tactical procedures that result in the decreased effectiveness of a directed energy weapon. These counters made use of operating location, operating conditions, and maneuvers to negatively affect the weapon’s performance.
The rapid growth and maturity has started another race among militaries, on one hand they shall seek to exploit these technologies for their gains as well as develop countermeasures to protect their own forces. Keeping pace with rapidly advancing directed energy weapons requires a sophisticated and pragmatic countervailing response.
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