EMP and HPM weapons disable electronic devices without causing physical damage. Here we explain how they work, which countries are leading the way, and how they are used in the field.
A definition of EMP and HPM weapons
Electromagnetic pulse (EMP) weapons and high-power microwave (HPM) weapons are part of the directed energy weapons category. They do not directly damage human bodies or structures, but neutralize electronic circuits and computer systems.
An EMP refers to an intense burst of electromagnetic energy, often produced by a high-altitude nuclear explosion (above 30 km), or by non-nuclear devices using fast-discharge capacitors. This pulse releases an electromagnetic field that extends over hundreds of kilometers. It can instantly disrupt or fry electronic systems, radars, power grids, and telecommunications.
HPMs work differently. They emit a focused beam of high-intensity radio waves in the microwave band (generally between 1 and 100 GHz). Unlike EMPs, HPM weapons target specific targets at short or medium range. They saturate or destroy sensitive electronic components such as processors, antennas, or motherboards.
These weapons do not cause conventional explosions or visible mechanical damage. They act on the invisible infrastructure of any modern army: sensors, networks, drones, satellites, command systems, aircraft, armored vehicles, and automated logistics bases.
EMPs were first theorized in the 1960s after US nuclear tests in space, notably the “Starfish Prime” test in 1962, which cut off electricity in Hawaii, more than 1,400 km away. Since then, non-nuclear versions have been at the center of military research programs.
How electromagnetic saturation works
The physical principle behind EMP weapons is based on the sudden displacement of electrical charges. A nuclear explosion at high altitude ionizes the atmosphere and generates fast-moving electrons that interact with the Earth’s magnetic field. This produces an extremely brief (nanosecond) but very powerful electrical pulse. The intensity can exceed 50,000 volts per meter.
In non-nuclear systems, flux compression generators or pulsed microwave systems are used. These compact devices can be installed in missiles or on mobile ground platforms. The weapon then emits a directed electromagnetic shock wave, targeting electrical networks and military equipment in a defined area.
HPMs use a millimeter wave transmitter powered by a concentrated energy source, such as a chemical explosive compressing a magnetic field or a battery-powered generator. They operate continuously or in bursts of a few milliseconds and can accurately target a satellite, drone, aircraft, or command center.
The range of a non-nuclear EMP system varies from a few hundred meters for portable weapons to several kilometers for ballistic missile-mounted devices. HPM weapons have a shorter range but greater accuracy, with effects localized within 1,000 meters.
Countries at the forefront of developing these weapons
Several military powers are actively working on EMPs and HPMs, in a context where electronic dominance has become a strategic priority. Three countries are at the forefront of development: the United States, China, and Russia.
The United States
The Pentagon has invested heavily in directed energy weapons programs. The US Air Force and DARPA have tested systems such as CHAMP (Counter-electronics High Power Microwave Advanced Missile Project), capable of flying over an area and neutralizing all electronic installations on the ground without noise or flash. In 2012, a test in Utah reportedly demonstrated CHAMP’s ability to disable multiple computer targets without causing collateral damage.
Ground-based prototypes are also under development, such as THOR (Tactical High-power Operational Responder), designed to shoot down swarms of drones. The budget allocated to HPM and laser systems reached €1 billion in 2023, according to a US Congressional report.
China
China has incorporated EMPs into its electronic warfare and “no-contact warfare” doctrines. The country has large-scale EMP simulation facilities and is working on non-nuclear directed-pulse warheads. The DF-21D missile could theoretically carry an EMP warhead designed to disable enemy aircraft carriers within a radius of several kilometers. In 2020, the Chinese military newspaper PLA Daily mentioned the integration of EMPs into anti-access/area denial (A2/AD) strategies.
Russia
Russia claims to have developed electromagnetic pulse weapons such as the “Alabuga” bomb, which can neutralize electronic systems within a radius of 3.5 km. Moscow considers these weapons to be a complementary tool in hybrid warfare. Several experts believe that the Russian army has been testing this type of weapon against Ukrainian infrastructure since 2022, particularly on radars and electrical networks.
Other countries such as South Korea, Israel, Iran, and India are developing similar projects, often aimed at neutralizing drones or defending sensitive infrastructure.
Strategic use on the battlefield
EMPs and HPMs are not intended to inflict human casualties, but to disrupt the enemy by depriving them of their command, communication, surveillance, and strike capabilities. These weapons are used as tools to launch or support more conventional operations.
On the modern battlefield, the digitization of systems makes armies highly vulnerable to this type of attack. Vehicles, aircraft, guided missiles, radars, and even ammunition are controlled by processors that are sensitive to electromagnetic pulses. An EMP can blind and deaf a mechanized battalion in seconds, destroying its navigation, coordination, and intelligence systems.
HPMs are particularly effective against drones. A targeted shot can disrupt their GPS link, disable their camera, or melt their onboard electronics. The US THOR system is designed for this purpose, as are the Israeli electromagnetic cannons used in urban testing.
On the defensive side, air bases and sensitive sites are gradually being equipped with electromagnetic shielding, Faraday cages, or redundant circuits to withstand such attacks. However, defenses remain imperfect and costly.
The use of these weapons in asymmetric conflicts, or against civilian infrastructure (power plants, transportation systems, satellites), also raises questions about the law of conflict and the limits of technological warfare.
EMP and HPM weapons are a discreet but powerful technological category capable of overturning the balance of power without conventional fire. Their effectiveness lies in their ability to paralyze electronic systems, which are now the lifeblood of any military operation. The United States, China, and Russia are making them a major focus of development, with concrete applications in modern theaters of operation. Their uses, which are still partially secret, are shaping the contours of a war in which control of electronics is becoming as strategic as superiority in conventional weapons.
War Wings Daily is an independant magazine.