Chapter IV. Technology Development
Army Science and Technology Master Plan (ASTMP 1997)

K. Electronic Warfare/Directed Energy Weapons

1. Scope

Electronic Warfare includes any military action involving the use of electromagnetic and directed energy to control the electromagnetic spectrum or attack an enemy. Electronic warfare comprises three major subdivisions: Electronic Attack—use of electromagnetic or directed energy to attack personnel, facilities, or equipment with the intent of degrading, neutralizing, or destroying enemy combat capability; Electronic Support—actions taken by, or under direct control of, an operational commander to search for, intercept, identify, and locate sources of radiated electromagnetic energy for immediate threat recognition in support of EW operations and other tactical actions such as threat avoidance, homing, and targeting; and Electronic Protection—actions taken to protect personnel, facilities, or equipment for any effects of friendly or enemy employment of electronic warfare that degrade, neutralize, or destroy friendly combat capability. Electronic warfare and directed warfare are leading technologies for solving Army problems in scenarios where non-lethal (i.e., no permanent injury) or less than lethal (i.e., could suffer serious injury) force is required.

Figure IV-K-1 illustrates DEW and jamming applications on the battlefield. Figure IV-K-2 depicts the electronic power relationships between electronic warfare jammers and RF-directed energy weapons.

Figure IV-K-1. Battlefield Applications of DEW and Jamming


Figure IV-K-2 Comparison of EW Jammer and RF-DEW Power Relationship


2. Rationale

As the roles, missions, and capabilities of today’s Army evolve into the 21st century, so then does the role of electronic warfare. Dominance of the electromagnetic spectrum based on the ability to use and deny its use by others at will is dependent on industry, academia, the other services, and a robust program to sustain the Army’s unique requirements on the electronic battlefield. As threat systems become more complex, the need to develop EW systems that can respond to changing environments is critical to superior battlefield surveillance and survivability. Technology to collect, recognize, and process complex wave forms and provide effective jamming are essential. Knowledge-based systems using artificial intelligence and adaptive parallel distributed processing can provide "smart" software control to maintain an edge on a dense signal battlefield.

3. Technology Subareas

a. Electronic Attack

Goals and Time Frames

Develop the technologies that provide the capability to intercept and bring under electronic attack advanced communications signals being used by adversarial command and control networks on the digital battlefield. Through electronic attack strategies demonstrated with prototype hardware and software, these digital communications signals will be disrupted, denied, and/or modified to render the communications system ineffective and unreliable to the threat command and control function. Near-term goals are to demonstrate electronic attack against a set of digital formats being implemented in commercial communications systems and data transmission systems. Mid-term goals are to demonstrate the ability to disrupt other commercial communication networks and wide bandwidth communications. Long-term goals include the ability to surgically attack specific users in a non-obtrusive means while maintaining the overall integrity of the targeted communications network.

Major Technical Challenges

The increasing use of common carrier commercial communications networks by potential adversaries presents the major technical challenge. We must be able to separate the threat-relevant communications from the pure commercial traffic and perform effective electronic warfare without disrupting the entire network. These targeted communication systems are characterized as adaptive sophisticated digital networks and modulation schemes that employ various layers of protocol and user protection.

Technology challenges include development of uncooled, low false alarm rate detectors with <1 degree AOA accuracy, development of multi-color IR focal plane arrays (Navy/Air Force Program), missile detection algorithms, and development of more efficient, low-cost, temperature stable IR/UV filters. The development of advanced high speed wideband digital receivers using GaAs microscan design approach, and the development of high power ultra-wide band jamming modulators and transmitter sources from A through M bands using MPM, MMIC, and fiber-optic remoting of sensors and transmitters. Precision AOA for situational awareness and targeting.

b. Electronic Support

Goals and Time Frames

As modern communication systems evolve, the overall goal is to develop the technology required to provide an ES/EA capability to intercept and counter these new priority threats and to provide the battlefield commander the tactical intelligence products that contribute to his ability to accomplish his mission. Near-term goals include the downsizing of existing bulky components to provide a rapidly deployable capability and the conversion from special purpose processors and software to a general purpose suite. The intent is also to provide the ability to specifically tailor and reprogram these systems quickly either locally or remotely to meet the current and changing threat. Mid-term goals include development of signal processing techniques that provide effective ES against common carrier, multiple access commercial communications in order to identify, locate, and exploit threat users. A second goal is the development of the tools required to display increasingly complex data to the soldier operators in support of the IEW mission. The long-term goal includes the continued development of adaptive sensor technologies that can perform the ES mission as the use of increasingly more complex communication systems continues to evolve.

Major Technical Challenges

The increasing use of common carrier commercial communications networks by potential adversaries presents the major technical challenge. This infers the need for advanced front end receiver architectures and signal processing techniques capable of providing ES mission functions against increasingly complex signal modulation methods and structures coupled to higher data rates and user protection schemes.

c. RF-Directed Energy Weapons

Directed Energy Weapons (DEW) include laser, high power radio frequency (HPRF), and particle beam technologies. HPRF technology is frequently called high power microwave (HPM) or RF-Directed Energy.

Electronic equipment can be defeated or impaired by irradiation from Directed Energy (DE) sources. Degradation can range from: (1) temporary "upsets" in electronics subsystems, (2) permanent circuit deterioration, or (3) permanent destruction due to burnout or electrical overload. As modern systems and their components become ever more reliant on sophisticated electronics, they also become more vulnerable to DE radiation. The Army’s DE program priority is to assess potential vulnerability of U.S. systems to unintentional irradiation "fratricide" by our DE capable systems as well as intentional irradiation by enemy DE systems. DE hardening technology is being developed to mitigate both of these threats. In addition, the Army S&T program provides sources and components to (1) support the susceptibility assessment program, (2) support possible future applications, and (3) avoid technological surprise from an adversary’s breakthrough.

Goals and Time Frames

Near-term goals for RF-DE weapons are (1) the demonstration of the interference modulation HPM source concept for use in susceptibility testing and in field tests, and (2) RF-DE weapons hardening for MMIC circuits used in Army systems. A mid-term goal is the development of High-Gain, broadband antennas. Long-term goals include development of silicon carbide hardening devices and use of chaos theory research results to achieve greater control of RF-DE weapon sources.

Major Technical Challenges

High power RF generators need to be smaller, lighter, and more fuel efficient. Projected targets require intensive susceptibility studies to determine the best attack methods. These technical challenges will be overcome by concentrating technology development efforts on improving modulators, RF sources, and antennas. Improvements to reduce size, weight, and power requirements must also be accomplished by enhancements to radiate beam control.

d. Lasers

Compact, high efficiency lasers are critical for electro-optical countermeasures (EOCM), infrared countermeasures (IRCM), and directed energy (DEW) applications. The maturation of diode pumped lasers, nonlinear frequency conversion techniques, and advanced laser design has made feasible the incorporation of these devices into tactical vehicles and aircraft for self-protection and missile defense. The challenge is to demonstrate the required power levels in a compact package for Army applications and to scale the power to higher levels for future needs.

Goals and Time Frames

One FY96 goal was to demonstrate compact mid-infrared lasers to meet an Army ATD requirement. This was accomplished under a DARPA/Tri-Service program that increased power by an order of magnitude. Optically and electronically pumped solid-state lasers that will transition to EMD by FY00 should have significantly lower cost, size, and power consumption. These lasers are being developed under a management agreement between DARPA and the Services. An Active Tracker System was developed under another DARPA program for IRCM/EOCM applications to provide precision pointing and atmospheric compensation. This technology was demonstrated in FY96. The DARPA/Army 10 Joule/100 Hz diode pumped laser (DAPKL) was demonstrated in the lab in FY95 and is scheduled to be packaged for delivery in FY97.

Major Technical Challenges

The major challenge to scaling the mid-infrared lasers is the development of an OPO (Optical Parametric Oscillator) which can handle the higher average powers without damage. Other issues are the packaging of lasers for use on aircraft and the cost reduction of laser diode arrays. A longer term challenge will be the scaling of compact solid-state lasers to higher powers for standoff directed energy applications.

Specific challenges include:

4. Roadmap of Technology Objectives

The roadmap of technology objectives for Electronic Warfare/Directed Energy Weapons is shown in Table IV-K-1, below.


Table IV-K-1. Technical Objectives for Electronic Warfare/Directed Energy Weapons

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