For decades, the idea of defeating enemy weapons with pure energy existed only in theory. Today, it is an operational reality. Around the world, militaries are investing in high-power microwave (HPM) systems, a form of directed-energy weapon that disables targets not with explosives or lasers, but with concentrated bursts of electromagnetic energy.

At its core, microwave defense technology converts electrical power into short, extremely intense pulses of electromagnetic radiation within the microwave frequency band, typically between 1 and 10 gigahertz. These pulses propagate outward at the speed of light, coupling into the circuitry of nearby drones, missiles, or sensors. When the microwave pulse strikes, it induces large voltage surges and thermal stress in electronic components, burning out processors, disrupting communication links, and rendering onboard systems inoperable.

Unlike radio-frequency jamming, which interferes only with control signals, or lasers, which require precision aim and continuous exposure, HPM systems can neutralize multiple targets in a single pulse. The wide beamwidth of a microwave emitter enables one-to-many engagements–a key advantage against the swarm tactics increasingly used by low-cost drones.

In the United States, two defense leaders are driving the field forward. Epirus, based in California, has developed the Leonidas system, a mobile HPM weapon designed for precision engagement and wide-area defense. In a U.S. Army live-fire event at Camp Atterbury, Indiana, Leonidas neutralized 61 drones across multiple flight profiles. The system’s solid-state emitters and software-defined architecture allow operators to shape the beam pattern and control energy output in real time. Its autonomous variant, Leonidas AR, integrates the same technology onto a robotic ground vehicle, providing mobility and adaptive positioning on the battlefield.

RTX’s Raytheon division has developed a complementary approach with its Phaser high-power microwave system. Mounted on a compact platform resembling a radar array, Phaser generates high-voltage pulses using a rapid power modulation system that drives a magnetron or solid-state source. Operators focus a broad, arcing beam on incoming drones, delivering a short, high-intensity burst that instantly burns out their electronics. During Air Force field tests, personnel learned to operate both Raytheon’s microwave and laser systems within a single day and successfully defeated drones in real-world conditions. The Air Force has since deployed Phaser overseas, marking the first operational use of a directed-energy weapon.

From an engineering standpoint, both systems solve several long-standing challenges of directed energy. Power generation is achieved through compact pulsed-power modules that store electrical energy in capacitors and release it within microseconds, creating a short but extremely powerful output. Advanced waveguides and phase-control circuits ensure beam stability and allow for dynamic retargeting between pulses. As microwaves do not rely on optical line-of-sight or precise atmospheric conditions, they remain effective in dust, rain, or fog, conditions where lasers might falter.

This technology also provides major logistical advantages. Unlike missile interceptors that must be reloaded or lasers that demand extensive cooling systems, microwave weapons can fire repeatedly as long as they have electrical power. Each “shot” costs only the energy consumed, making them a cost-effective countermeasure against inexpensive drone threats.

The strategic implications are significant. As modern battlefields become saturated with autonomous aerial systems, high-power microwave weapons offer scalable protection for forward bases, armored vehicles, and critical infrastructure. They can operate as standalone systems or be layered with radar, laser, and kinetic defenses to form a comprehensive shield against diverse aerial and electronic attacks.

Companies like Epirus and RTX are demonstrating how microwave defense has matured from theoretical research into deployable reality. Their work reflects a broader transformation within the defense sector, one that merges electrical engineering, software control, and battlefield integration. The result is a new generation of weapons defined not by speed of flight, but by speed of energy.