The EW World
Written by Peter Buxbaum
TISR 2011 Volume: 1 Issue: 4 (October)
Electronic warfare (EW) used to refer to the detection and jamming of radio frequencies, making communications by an adversary difficult. No longer.
Today’s electronic warfare is focused on any weapons system or device uses or creates signals in the electromagnetic spectrum from radios and radars to controls for improvised explosive devices. Electronic warfare countermeasures also protect vehicles and aircraft by identifying and evading munitions based on their electromagnetic signature. Electronic warfare refers to the use, and the denial of use, of the electromagnetic spectrum by a broad range of electronic technologies.
One growing challenge in the electronic warfare arena involves the protection of unmanned aerial vehicles, which are increasingly being deployed to gather tactical ISR. Advances in computing, which allow UAVs to exercise greater degrees of autonomy, are helping in this area. EW applications often must detect, tune to and locate a transmission in an extremely brief period of time. Specialized antennas and tuners as well as high-speed real-time computing capabilities also help protect lives and assets by identifying threats and deploying countermeasures within very narrow time frames.
“Everyone used to think that electronic warfare was tied to the jamming of radios signals,” said Roger Nadeau, vice president for land and C4I solutions at Elbit Systems of America. “That is not true anymore.”
Electronic warfare today has moved conceptually beyond the compromise or protection of communications and other assets. “Electronic warfare in a wider sense is about creating situational awareness,” said Steve Roberts, chief technical officer for electronic warfare at Selex Galileo. “It is about collecting information that can contribute to situational awareness, not just for the platform but also for the force the platform is supporting.”
“Electronic warfare now covers a variety of things that involve what you can do to influence an adversary and to protect your own systems against the influence of others,” added Nadeau. “Gone are the days where radios function on specific frequencies. There is no longer a push-to-talk mentality. You can’t design a radio system in which electronic warfare countermeasures are not designed into the system.”
Elbit Systems of America is a subsidiary of Elbit Systems Ltd. (ESL), a company based in Haifa, Israel. ESL divisions have supplied electronic warfare systems to a European country and have supplied electronic warfare equipment for a Canadian Navy frigate modernization program as a subcontractor of Lockheed Martin.
The technical challenges faced by today’s electronic warfare is often compounded by the need to rapidly develop and deploy new application capabilities, sometimes on small platforms operating in harsh environments. “We help address these challenges by developing innovative technologies, then integrating them together to create powerful, effective solutions,” said Tom Roberts, solutions marketing manager at Mercury Computer Systems.
The broadening of the scope of electronic warfare has been facilitated by developments in weapons systems. “Most weapons use some portion of the electromagnetic spectrum,” said Steve Roberts. “It could be radio transmissions or radar to control a missile, the ultraviolet flash of a missile launch, or ultraviolet or infrared activity from a gun.”
Selex Galileo’s AGP integrates a suite of sensors to provide an aircraft crew with a combined threat picture and countermeasures which recommend a tactical response.
“The AGP has been selected by Boeing for integration into the Block II and Block III AH64D Apache and a variant is used by the United Kingdom Ministry of Defence for front-line combat helicopters,” said Steve Roberts. “The box provides enhanced platform survivability and reduced crew workload by increasing situational awareness of the threat environment and the initiation of optimized countermeasure responses.”
Prioritized threats are shown on multifunction displays with coordinated audio warnings. “This box knows the capabilities of the platform and the available countermeasures,” said Roberts. “It knows what to do when it sees a particular threat.” The AGP evolved from the Helicopter Integrated Defensive Aids System (HIDAS), first deployed on the British variant of Apache.
The technology was first deployed 15 years ago aboard Royal Navy vessels. The size of the system has since been reduced to a box weighing less than eight pounds.
HIDAS protects rotary wing aircraft by identifying hostile weapon systems and initiating appropriate tactics and countermeasures. HIDAS utilizes multispectral sensors and preloaded intelligence to produce comprehensive pictures of the operating environment.
Components of HIDAS include radar and laser warning receivers and a missile warning system as well as infrared and radio frequency countermeasures. “HIDAS detects, identifies, prioritizes and counters threats to helicopters, without the need for crew intervention,” said Steve Roberts. “It is an advanced integrated defensive aids system tailored for helicopters. HIDAS utilizes mission-specific data entered by the user at the flight line.” After extensive testing and trials on airborne platforms, HIDAS has been very successful on operations.
An advanced countermeasure system which recently emerged from laboratory and toward flight tests is Selex Galileo’s Economic Compact Lightweight Pointer-tracker System (ECLIPSE), an infrared pointer tracker. Selex Galileo recently won the competition to supply its next generation ECLIPSE to a U.K. Ministry of Defence aircraft protection program.
Selex Galileo has also developed a product to defeat radar in the form of the Ariel towed radar decoy. The technology was first deployed during the first gulf war and then in Kosovo. “Variations of the towed decoy have been in service since 1990 and used on the Eurofighter Typhoon, Tornado and Nimrod aircraft,” said Steve Roberts. “The first generation of towed decoys was flown successfully in the Balkans and over Iraq enabling crews to operate with a higher degree of safety in hostile skies providing protection against numerous surface-to-air systems.”
The Ariel countermeasure is towed behind the aircraft to lure enemy missiles away from their targets by providing a larger radar cross section than the aircraft. The decoy also incorporates the latest jamming techniques. Ariel communicates with onboard systems to transmit specific deception techniques designed to defeat incoming missiles and hostile radars.
“Ariel has been proven to defeat radio frequency-guided weapons,” said Steve Roberts. “The decoy can be installed and operated from all types of fixed wing aircraft including high-performance supersonic combat aircraft.” The increased use of UAVs for tactical ISR calls for somewhat enhanced electronic warfare capabilities. “The threats are similar to those facing manned aircraft,” said Roberts. “The difference is that the aircraft requires some degree of autonomy to detect threats and take evasive action and countermeasures.” In other words, UAVs can use systems similar to those found on manned aircraft but without the crew making the final decision on evasion and countermeasures.
Electronic warfare capabilities have continually been scaled down in size in recent years so that even smaller UAVs can be equipped with sensor suites and decision-making capabilities similar to those found in larger aircraft, according to Roberts.
Within the guts of these electronic warfare systems are the high speed computing capabilities as well as the specialized antennas, tuners, converters and digital receivers required to absorb information and make decisions on the fly. Mercury Computer Systems does not produce electronic warfare systems but works with prime contractors who do, providing those kinds of components.
Mercury contributed its high-speed tuners to the Joint Counter Radio-Controlled Electronic Warfare (JCREW), said Tom Roberts. “IEDs are activated by a variety of devices such as cell phones and garage door openers,” he explained. “The system had to be able to tune quickly so that jamming can be put in to place before the circuit is completed. The components also had to fit on a small platform.” JCREW 3.3, the latest iteration, is being developed to be adaptable to a variety of applications such as mounted and dismounted soldiers as well as protection for fixed installations.
Last year, Lockheed Martin won the contract for the Block 2 upgrade of the Surface Electronic Warfare Improvement Program (SEWIP) using Mercury components. SEWIP is providing the Navy with a series of enhancements to its current EW system in an approach that incorporates commercial off-the-shelf electronics.
Mercury Computer recently introduced three new components for electronic warfare applications: the RFM-1802, a dual-channel wideband microwave tuner; an eight-channel digital receiver; and a small multichannel digital receiver. “When combined with powerful processing power, these innovations unleash new capabilities such as fast and sophisticated direction finding,” said Tom Roberts.
The new tuner is attractive to new EW programs based upon its fast tuning capability, said Roberts. “With ultra-fast tuning speed,” he explained, “a single channel views a very wide instantaneous bandwidth over an even larger frequency range. This window can be shifted, or retuned, nearly instantaneously, allowing systems to track sophisticated, modern-day waveforms. Fast tuning to help with direction finding is critical to the SEWIP.”
The RFM-1802 tuner has been complemented by a new 8-channel option added to Mercury’s digital receivers, which include the necessary resources for signal processing functions.
“Every electronic warfare program has its own needs,” said Tom Roberts. “With SEWIP one of the needs was very fast tuning. Threats are getting more sophisticated, employing frequency hopping and quick short signals making them hard to find.”
Mercury’s products are built to open standards, Roberts noted. “That makes it easier to refresh subsystems,” he said. “Newer, faster and more advanced components can be incorporated into systems quicker and at lower cost. Proprietary interfaces can lock customers in. The Department of Defense and industry participants have moved away from that.”
Future developments will see sensor and processing packages getting ever smaller, according to Roberts, allowing them to be mounted on platforms such as smaller UAVs. “These systems won’t be limited to use on platforms like the Global Hawk or Predator,” he said. “Aircraft like the Shadow will also be able to carry EW packages.”
For Steve Roberts, future innovations will likely revolve around the processing of data absorbed by EW sensors. “Different kinds of sensors will be able to pass messages among themselves and to the central system,” he said. “The decision making element won’t need to know much about what kind of sensor detected a potential threat or how the detection was made.”
Much as UAVs will require greater on-board autonomy to evade and counter threats, coming EW systems will also exercise discretion about what data and information to present to their human handlers. “Sensors remain important but the processing of the data is becoming increasing important,” said Roberts. “The processing will be focused on extracting information from pictures rather than presenting pictures to humans to for them to process. We have been working on reducing and simplifying the amounts of data presented to those showing changes or events or interest.” ♦