The future of the battlefield will be closely tied in with the advance of electronics computers, robots and sensors will become more common on the future battlefield. Infantrymen are being equipped with digital radios and computers. Night vision devices have been around for some time. Tanks have highly sophisticated targeting computers, radar and imaging devices. All these devices are electronic in nature.
As these devices become more and more common they will be integrated into helmets, weapons, and battle suits. Vehicles will become highly automated and detection of the enemy will become easier. As weapons become more lethal it will become more important to have an advantage over the enemy. However, electronics are not invulnerable.
In the past, the threat of mutually assured destruction provided a lasting deterrent against the exchange of multiple high-yield nuclear warheads. However, now a single, specially-designed low-yield nuclear explosion high over a battlefield can produce an EMP effect that results in a widespread loss of electronics, but no direct fatalities.
The possible vulnerability of commercial electronics and military battlefield equipment to the effects of EMP may create a new incentive for many emerging countries in the world to develop or acquire a nuclear capability.
High Power Electromagnetic Pulse generation techniques and High Power Microwave technology have matured to the point where practical E-bombs are becoming technically feasible, with new applications in both strategic and tactical information warfare. The development of conventional E-bomb devices allows their use in non-nuclear confrontations.
The United States most likely has EMP weapons in its arsenal, but it’s not clear in what form. Much of the United States’ EMP research has involved high power microwaves (HPMs).
Most likely, the United States’ HPM e-bombs aren’t really bombs at all. They’re probably more like super powerful microwave ovens that can generate a concentrated beam of microwave energy. One possibility is the HPM device would be mounted to a cruise missile, disrupting ground targets from above.
This technology is advanced and expensive and so would be inaccessible to military forces without considerable resources. But that’s only one piece of the e-bomb story. Using inexpensive supplies and rudimentary engineering knowledge, a terrorist organization could easily construct a dangerous e-bomb device. It is estimated that a limited-range suitcase-sized HPM weapon could be constructed for much less than $2,000, and is within the capability of almost any nation, and perhaps many terrorist organizations. Additionally, the explosives used in a smaller or suitcase-sized HPM device could simultaneously be used to disperse radioactive materials, making it a so-called “dirty bomb”. This combination would offer a possible two-for-one effect, where the dispersed radioactive materials could generate immediate near-panic, while the HPM-damaged computers might not be noticed until days later. This potential double effect could improve the attractiveness of using an HPM device as a terrorist weapon.
An electromagnetic pulse (EMP), characterized as an energy weapon potentially threatening to national security, usually is created by two methods. High-Altitude Electromagnetic Pulse (HEMP) is an electromagnetic energy field produced in the atmosphere by the power and radiation of a nuclear explosion, and that is damaging to electronic equipment over a very wide area, depending on the design of the nuclear device and altitude of the burst. High-Power Microwave (HPM) is an electromagnetic pulse produced with special equipment that transforms power from batteries, or from a chemical explosion, into intense microwaves that are very damaging to electronics within a much smaller area.
In addition, while HEMP weapons are large in scale and require a nuclear capability along with technology to launch high altitude missiles, HPM weapons are smaller in scale, involve a much lower level of technology, and may be within the capability of many non-state organizations.
Electromagnetic pulse and High Powered Microwave weapons offer a significant capability against electronic equipment susceptible to damage by transient power surges. The conventional Electromagnetic pulse and High Powered Microwave weapons can disable non-shielded electronic devices including practically any modern electronic device within the effective range of the weapon.
There are two kinds of damage electromagnetic pulse can cause to electrical or electronic systems. First is the actual physical damage caused by electrical components shorting out or burning out such as capacitors, resistors, and transistors, thus causing the repair or replacement of the component. The second is of lesser concern because it causes only temporary operational upsets such as instabilities; causing the system to shut itself down, upset computers so they must be started again. Both these effects increase in direct proportion to the amount of digital technology and the large scale integrated circuitry designed into our systems.
It is significant that modern military platforms are densely packed with electronic equipment, and unless these platforms are well hardened, an electromagnetic pulse device can substantially reduce their function or render them unusable.
EMP weapons come in a variety of forms, differing in cost, complexity, and lethality to electronic systems. Regardless of the type, they offer the user many significant advantages. Firstly, EMP weapons do not rely on in-depth knowledge of the systems they strike, attacking all electronic systems without prejudice. Secondly, they are effective in all weather. Thirdly, they are area weapons, with scalable footprints. Fourthly, they produce persistent and lasting effects through destruction of circuits. Fifthly, to counter EMP, entire systems must be hardened from end-to-end, a costly defense effort. Lastly, and perhaps most importantly, EMP weapons don’t hurt people directly.
EMP weapons can be classified as nuclear, high power microwave (HPM), or electromagnetic bomb (e-bomb). Each has its own characteristics, but all are constrained by the fact that they need a clear line-of-sight to the target to be effective.
The concept behind the e-bomb arose from nuclear weaponry research in the 1950s. The Russians were the first to understand the implications of EMP as a weapon. Soviet physicist Andrei Sakharov proposed using this principle in a bomb in the 1950s. On October 22, 1962, during one of their ABM tests, the Russians detonated a 300 kiloton hydrogen warhead (20 times more powerful than Hiroshima) at an altitude of 300 km over Kazakhstan.
The United States military realized EMP’s potential as a weapon the same year, in the Starfish Prime test of a much larger 1.44 megaton warhead at a height of 400 km over the Pacific Ocean. The pulse knocked out street lights and damaged telephones in Hawaii. Four days after the explosion the UK satellite Ariel was unable to generate sufficient electricity to function properly and radio equipment was affected as far as away as Australia. Although at the time these effects were considered incidental, since that time researchers have sought a means of focusing that energy.
The EMP effect was first observed during the early testing of high altitude airburst nuclear weapons. The effect is characterized by the production of a very short (hundreds of nanoseconds) but intense electromagnetic pulse, which propagates away from its source with ever diminishing intensity, governed by the theory of electromagnetism.
The Electro Magnetic Pulse is in effect an electromagnetic shock wave. This pulse of energy produces a powerful electromagnetic field, particularly within the vicinity of the weapon burst. The field can be sufficiently strong to produce short lived transient voltages of thousands of Volts (ie kiloVolts) on exposed electrical conductors, such as wires, or conductive tracks on printed circuit boards, where exposed.
It is this aspect of the EMP effect which is of military significance, as it can result in irreversible damage to a wide range of electrical and electronic equipment, particularly computers and radio or radar receivers. Subject to the electromagnetic hardness of the electronics, a measure of the equipment’s resilience to this effect, and the intensity of the field produced by the weapon, the equipment can be irreversibly damaged or in effect electrically destroyed. The damage inflicted is not unlike that experienced through exposure to close proximity lightning strikes, and may require complete replacement of the equipment, or at least substantial portions thereof.
Computers used in data processing systems, communications systems, displays, industrial control applications, including road and rail signaling, and those embedded in military equipment, such as signal processors, electronic flight controls and digital engine control systems, are all potentially vulnerable to the EMP effect.
Other electronic devices and electrical equipment may also be destroyed by the EMP effect. Telecommunications equipment can be highly vulnerable, due to the presence of lengthy copper cables between devices. Receivers of all varieties are particularly sensitive to EMP, as the highly sensitive miniature high frequency transistors and diodes in such equipment are easily destroyed by exposure to high voltage electrical transients. Therefore radar and electronic warfare equipment, satellite, microwave, UHF, VHF, HF and low band communications equipment and television equipment are all potentially vulnerable to the EMP effect.
It is significant that modern military platforms are densely packed with electronic equipment, and unless these platforms are well hardened, an EMP device can substantially reduce their function or render them unusable.
A major advantage of using electromagnetic bombs is that they may be delivered by any tactical aircraft capable of delivering GPS guided munitions. Because of the simplicity of electromagnetic bombs in comparison with weapons such as Anti Radiation Missiles (ARM), it is not unreasonable to expect that these should be both cheaper to manufacture, and easier to support in the field, thus allowing for more substantial weapon stocks.
Protection and limitation
It is easy to say one can protect electronic equipment against electromagnetic pulse in principle but it is very difficult to implement and even more difficult to maintain. There are two basic methods of providing electromagnetic pulse protection. The first is to design and build the equipment so that the circuit can resist the electromagnetic pulse. The second is to provide a shield, which will not allow the electromagnetic pulse to enter. Often the most cost effective way is to use a combination of both methods to defeat the electromagnetic pulse
Alternate effort against electromagnetic bombs is to prevent their delivery by destroying the launch platform or delivery vehicle, as is the case with nuclear weapons. This however may not always be possible, and therefore systems which can be expected to suffer exposure to the electromagnetic weapons effects must be electromagnetically hardened.
The most effective method is to wholly contain the equipment in an electrically conductive enclosure, termed a Faraday cage, which prevents the electromagnetic field from gaining access to the protected equipment. However, most such equipment must communicate with and be fed with power from the outside world, and this can provide entry points via which electrical transients may enter the enclosure and effect damage. While optical fibres address this requirement for transferring data in and out, electrical power feeds remain an ongoing vulnerability.
A range of devices exist, however care must be taken in determining their parameters to ensure that they can deal with the rise time and strength of electrical transients produced by electromagnetic devices. Reports from the US indicate that hardening measures attuned to the behavior of nuclear EMP bombs do not perform well when dealing with some conventional microwave electromagnetic device designs.
It is significant that hardening of systems must be carried out at a system level, as electromagnetic damage to any single element of a complex system could inhibit the function of the whole system.
Shielding the environment is a cost-effective solution for EMP protection when a large number of essential electronic devices are collocated.
Communications networks for voice, data and services should employ topologies with sufficient redundancy and failover mechanisms to allow operation with multiple nodes and links inoperative. This will deny a user of electromagnetic bombs the option of disabling large portions if not the whole of the network by taking down one or more key nodes or links with a single or small number of attacks.
The limitations of electromagnetic weapons are determined by weapon implementation and means of delivery. Weapon implementation will determine the electromagnetic field strength achievable at a given radius, and its spectral distribution. Means of delivery will constrain the accuracy with which the weapon can be positioned in relation to the intended target.
This underscores another limitation of electromagnetic weapons, which is the difficulty in kill assessment. Radiating targets such as radars or communications equipment may continue to radiate after an attack even though their receivers and data processing systems have been damaged or destroyed. This means that equipment which has been successfully attacked may still appear to operate. Conversely an opponent may shut down an emitter if attack is imminent and the absence of emissions means that the success or failure of the attack may not be immediately apparent.
Means of delivery will limit the lethality of an electromagnetic bomb by introducing limits to the weapon’s size and the accuracy of its delivery. Should the delivery error be of the order of the weapon’s lethal radius for a given detonation altitude, lethality will be significantly diminished. This is of particular importance when assessing the lethality of unguided electromagnetic bombs, as delivery errors will be more substantial than those experienced with guided weapons such as GPS guided bombs.
Numerous foreign governments have invested in hardening programs to provide some protection against nuclear EMP attack, indicating that this threat has broad international credibility. At least some of the new nuclear weapon states are concerned that their military command, control, and communications may be vulnerable to EMP attack.
According to a report prepared for the United States Congress, Russia and China are now capable of launching a crippling high EMP strike against the United States with a nuclear-tipped ballistic missile, and other nations, such as North Korea, could possibly have the capability by 2015. Other nations that could possibly develop a similar capability over the next few years include France, Israel, India, the UK and Pakistan.
According to a US DOD report, China is actively pursuing the development of electromagnetic pulse weapons, and is devoting significant resources to development of other electronic warfare systems and laser weapons. The report also notes that China’s leaders view offensive counter space weapons and other space-based defense systems as part of inevitable scenarios for future warfare.
Although India, Pakistan, and Israel are not rogue states, they all presently have missiles and nuclear weapons giving them the capability to make EMP attacks against their regional adversaries. United States perceives that an EMP attack by any of these states even if targeted at a regional adversary could collaterally damage US forces in the region, and would pose an especially grave threat to US satellites.
Many foreign analysts particularly in Iran, North Korea, China, and Russia view the United States as a potential aggressor that would be willing to use its entire panoply of weapons, including nuclear weapons, in a first strike. They perceive the United States as having contingency plans to make a nuclear EMP attack and as being willing to execute those plans under a broad range of circumstances.
However, India has declared that Defence Research and Development Organisation (DRDO) is developing an E-bomb which will emit electromagnetic shock waves that destroy electronic circuits and communication networks of enemy forces. The electromagnetic shock wave from the bomb will destroy electronic circuits and communication network “while paralyzing them in terms of radars, communication networking, information gathering sensors, controls and other electronic equipment. Work is in full swing at the Research Centre Imarat, the Hyderabad-based laboratory of DRDO, to build the new bomb which will be ready for operational deployment within a few years.
The E-bomb would give an option to the military as the bomb can target the enemy’s mobile targets, air defence systems, mobile or static radars, naval vessels with communication systems and even ill-shielded communication or electronic systems at a military base. The GPS-guided E-bombs would precede the conventional munitions for strategic air attacks and can cripple military units as weapons of electric destruction by releasing high voltage pulses. The E-bomb warheads can be delivered by combat aircraft equipped to deliver guided munitions and cruise missiles.
DRDO is also developing the next generation of smart bombs or guided bombs, which would have a longer range of upto 100 km and higher accuracy. Smart bombs are basically precision guided munition equipped with electronic sensors, control system and adjustable flight fins for providing steering or gliding capacity to hit a designated target with much more accuracy.
But to create an effective e-bomb, developers must not only generate an extremely high-powered pulse of energy, but must also find a way to control both the energy – which can behave in unpredictable ways – and the heat generated as its byproduct. Furthermore, for non-nuclear e-bombs, the range is limited.
EMP poses a massive threat to militaries around the world through its potential to isolate forces and deny access to regions. Even more ominous is the fact that the means to produce EMP effects, both nuclear and non-nuclear, are proliferating. Countries must face the looming EMP threat immediately and develop measures that will reduce the likelihood of an EMP strike, maintain the military advantage in the event of theater attack, and increase the nation’s chance for surviving a homeland attack. Through diplomacy, hardening of critical systems, training, and the establishment of industry standards to ensure future procurement of EMP-resilient systems, nations can prevail against one of the most serious near-term threats.
As training nowadays is a critical component of militaries, countries need to start integrating EMP scenarios into training exercises. One of the immediate effects of an attack would be loss of communications and situational awareness, which could lead to paralyzing confusion if not planned for and practiced.
In the near term, training should emphasize response options for current fielded forces, forces develop standard procedures to immediately restore communications, use UHF instead of VHF radios, shut down and protect unneeded radios for later use as backups, use small antennas, keep cable runs short, run cables on the ground, shield critical components, ground all equipment, and avoid use of commercial power to decrease vulnerability to EMP.
However, E-bombs can be an affordable force multiplier for military forces which are under post Cold War pressures to reduce force sizes, increasing both their combat potential and political utility in resolving disputes. But it is important that governments and defence industry should consider the implications of the proliferation of this technology, and take measures to safeguard their vital assets from possible future attack.