Phase: Phase II Amount: $1,165,930 Agency: Department of Defense Recipient: SCIENTIFIC APPLICATIONS & RESEARCH ASSOCIATES, INC. Award Date: July 2022 Project Summary: A portable system that appears to use laser-triggered switches to generate simulated electromagnetic pulses, potentially allowing the military to test whether critical electronics can survive nuclear detonation or directed energy weapon attacks. This project develops a mobile testing system that simulates the electromagnetic pulse (EMP) released by a nuclear explosion high in the atmosphere. The system works by using specially designed laser triggers to fire gallium arsenide switches—semiconductor devices (specialized electrical components made from materials that respond to light) that can handle extremely high voltages—which then drive antenna arrays that broadcast powerful electromagnetic fields at a test target. The key innovation appears to be making this technology compact and portable. Rather than requiring a massive fixed facility, the team developed a 100,000-volt pulse charger and a laser trigger system that may fire multiple switches nearly simultaneously with extremely precise timing (less than 300 picoseconds of variation, or about a trillionth of a second). This allows them to create a 3x3 antenna array that could approximate the early-stage electromagnetic effects of a nuclear EMP, potentially giving military engineers a way to test whether their equipment would survive such an attack. Currently, testing electronics against EMP threats generally requires either expensive fixed laboratory facilities or relies on theoretical models that may not perfectly match real-world conditions. The military needs practical, realistic testing to help ensure mission-critical systems won't fail during an actual EMP event, but existing simulators tend to be either too large to move or too expensive to build. This project appears to address that gap by creating a modular, portable system that could be transported to different locations and set up to test equipment in realistic field conditions. The precision laser trigger system seems novel in that it can potentially fire many switches in close synchronization, which may be essential for creating uniform electromagnetic fields that approximate actual EMP signatures. Military bases might use this system to test whether radar systems, communications equipment, and command-and-control electronics could withstand an EMP attack before deploying them in the field. Defense contractors designing new military hardware could potentially use it to certify their products meet EMP hardening standards, helping avoid costly failures in actual combat scenarios. Government agencies responsible for critical infrastructure—like power grid operators or telecommunications networks—could conceivably use the portable simulator to test whether their backup systems would survive a directed-energy weapon attack or nuclear detonation. For Taxpayers: This system could reduce the cost of EMP testing by potentially eliminating the need to build multiple fixed test facilities across different military installations. It may accelerate the development of hardened electronics by allowing faster, iterative testing during design phases, which could catch vulnerabilities early before expensive production mistakes occur. The portable design suggests the same equipment might serve multiple bases and agencies, potentially maximizing the return on the government's research investment. For Science: The work appears to advance the field of pulsed-power electronics by demonstrating practical techniques for synchronizing multiple high-voltage switches with nanosecond-level precision (billionths of a second). Other researchers could potentially build on the laser trigger design and antenna array architecture to develop improved EMP simulators or apply similar switching techniques to other high-power applications like medical imaging or materials processing. For Humanity: Helping ensure that military and civilian critical infrastructure can survive electromagnetic attacks may reduce the risk of widespread system failures that could harm public safety and national security. This work could indirectly support civilian infrastructure protection, since the same hardening principles explored here would likely apply to power grids, hospitals, and emergency response systems that depend on reliable electronics. Scientific Applications & Research Associates (SARA), Inc. is a 100% employee-owned small business based in Cypress, California, founded in 1989. The company specializes in technology solutions in areas such as RF, EMP, Pulsed Power, Acoustics, and Threat Warning, primarily serving the defense and aerospace sectors. With a workforce of approximately 157-206 employees, SARA focuses on developing customized technologies for U.S. military and commercial applications, emphasizing innovation and rapid development. SARA designs and manufactures a range of products, including measurement and analysis systems, RF shielding solutions, and advanced threat detection systems. Their offerings include the Artificial Perception and Threat Awareness (APTA) Group, which provides compact systems for RF geolocation and acoustic-based threat detection. The company supports various government agencies, including the Defense Threat Reduction Agency (DTRA) and the Department of Defense (DOD), in testing and standards development. SARA is committed to delivering cost-effective solutions and maintaining high standards in research, design, and production. Key Info: - Founded: 1989 - Employees: 210 - Revenue: 27.2M - Address: 6300 Gateway Drive, Cypress, CA 90630, US - Website: sara.com Status: Closed (100.0% Complete) Period of Performance: 7/7/22 to 7/6/24 Award Year: 2022 Contract: HDTRA118C0056 Agency Tracking #: T2S-0006 Solicitation #: 16.A Topic Code: DTRA16A-004 DUNS: 614108918 Branch: Defense Threat Reduction Agency For effective protection against radiated threats, produced by high altitude electromagnetic pulse (HEMP) caused by nuclear detonations and high-power microwave (HPM) Directed Energy (DE) weapons it is important to understand not only the physics of the threats, but also to quantify the effects on mission-critical electrical systems. EMP/HPM simulators enable threat level testing of MCS and provide stakeholders valuable quantitative information pertaining to such threats so that engineering principals, risk mitigation designs/protocols, and countermeasures can be implemented. The protection of MCS is necessary to ensure the integrity and survivability of government and economic assets from HEMP and HMP events. HEMP vulnerability and susceptibility testing requires the delivery of high peak power and high peak electric fields to targets. The most practical solution to simulate such environments on mission -critical systems is to develop a modular, portable, optically isolated MV-antenna array. This proposal presents an inexpensive 100 kV Pulse Charger and a low-jitter Laser Trigger System capable of simultaneously driving many gallium arsenide (GaAs) photoconductive semiconductor switches (PCSS) to drive largescale antenna arrays with <300 ps of timing jitter. The goal is to fabricate a mobile EMP simulator capable of generating the early time E1 portion of a HEMP event. To prevent damaging the GaAs PCSS, the primary charge storage capacitor and GaAs PCSS must be pulse charged to ± 50 kV in less than 10 us, therefore limiting the voltage seen by the switch. The developed pulse charger architecture has achieved ≈ 100 kV differential output in < 4 ms. The developed Q-switched laser system has operating wavelength of 840 nm, optical pulse rise time (10 to 90 %) of 3-4 ns, pulse width (FWHM) of 10 - 15 ns. The pulse energy delivered to each GaAs PCSS is >1500 mJ and spread over about 3 cm2 (500 mJ/cm2) and provides prompt triggering with peak power exceeding 100 kW. The primarily focus of the proposed effort will be on designing an improved and novel antenna radiator which minimizes impedance mismatches, demonstrating the 3x3 array to be a viable E1 EMP simulator test option, comparing acquired electric field data to openly available published data on existing E1 standards, and electric field characterization of the improved single horn antenna and array.