Military Embedded Systems

U.S. Navy's electronic warfare modernization effort centers on COTS


September 03, 2015

Sally Cole

Senior Editor

Military Embedded Systems

"Block 2" of the U.S. Navy's Surface Electronic Warfare Improvement Program is the first commercial off-the-shelf (COTS) electronic warfare system to be built.

The U.S. Navy’s Surface Electronic Warfare Improvement Program (SEWIP) is a series of evolutionary development “block” upgrades for Raytheon’s (Waltham, Massachusetts; legacy AN/SLQ-32(V) electronic warfare system, designed to provide incremental capability enhancements to enable its ships to continue to outpace threats.

Introduced in the late 1970s, the original AN/SLQ-32 electronic warfare system’s mission was to provide early detection, signal analysis, threat warning, and protection from anti-ship missiles. The integrated shipboard combat system is equipped with a full suite of electronic warfare capabilities that can be managed and controlled manually from a console either semi-manually or automatically by the host combat management system, according to the Navy.

In 2013, 258 electronic warfare systems, in seven variants, were deployed worldwide. The current SEWIP upgrade effort features four blocks – with a significant focus on obsolescence mitigation – for these electronic warfare systems.

The evolving electronic warfare threats the Navy is facing now involve such aspects as wider frequency bands, low power signals, frequency diversity, complex emitters, electromagnetic capability/electromagnetic interference, and flight profiles.

SEWIP Block 1

Block 1 focused on enhancing electronic warfare capabilities of existing and new ship combat systems to improve anti-ship missile defense together with countertargeting and countersurveillance capabilities. Obsolescence mitigation was addressed for Block 1 by incorporating electronic surveillance enhancements and improved control and display.

SEWIP Block 2

Block 2 upgrades are currently underway and are designed to provide enhanced electronic support capability by upgrading the electronic support antenna and receiver, as well creating an open combat system interface for the AN/SLQ-32.

The Navy awarded Lockheed Martin (Bethesda, Maryland; a $154 million contract to upgrade the fleet’s electronic warfare defenses against evolving threats.

Under this Block 2 contract, Lockheed Martin is providing additional systems to upgrade the AN/SLQ-32 systems on U.S. aircraft carriers, cruisers, destroyers, and other warships with key capabilities to determine whether or not the electronic sensors of potential foes are tracking the ship.

As another part of this deal, Mercury Systems Inc. (Chelmsford, Massachusetts; was awarded a $7.1 million contract by the U.S. Naval Warfare Center’s Crane Division to supply advanced radio frequency tuners, digital receivers, and related equipment to Lockheed Martin to be used as spares during the installation of the AN/SLQ-32(V)6 electronic countermeasures system on U.S. Navy and Coast Guard ships.

“The Navy’s electronic warfare focus is on electromagnetic dominance,” says Joe Ottaviano, Electronic Warfare program director for Lockheed Martin Mission Systems and Training.

In other words, it’s necessary to be able to detect threats working in signals ranging from low-frequency RF to those within the visible light and infrared parts of the spectrum. “This is a push not only by the Navy but also the entire Department of Defense. Technology is enabling threats to become more complex, so the systems that deal with threats are also increasingly complex,” Ottaviano notes.

Responding to threats with a hardware change is no longer considered acceptable, for example. “Threats need to be dealt with through on-the-fly system upgrades rather than waiting for a new hardware piece to become available,” Ottaviano explains. “So we’re seeing a shift toward DC-to-daylight systems to outpace threats.”

Electronic warfare is a much different type of challenge than radar, because while a radar knows when a signal was sent, what sent it, what it looks like, its intent, and roughly when it will return and what it will look like, typical electronic warfare systems – whether RF-based or based on visual electro-optics – can’t determine any of these properties. “But the purpose of electronic warfare is to determine a signal’s intent quickly to assess whether or not it’s a threat to ongoing operations,” points out Ottaviano.

Block 2 creates open, reprogrammable architecture

In terms of Lockheed Martin’s involvement in the Navy’s SEWIP Block 2, the goal is to help keep pace with expanding threats – bandwidths becoming wider – by upgrading the antenna, receiver, and processing systems. This capability began with Block 1. “Block 2 is the first step toward creating an open architecture with a reprogrammable on-the-fly-type electronic warfare system for the Surface Naval platforms,” Ottaviano says. “The blocks of SEWIP all build off each other – each one brings more capability,” he says.

Block 2, in particular, zeroes in on detection. It encompasses an open “agnostic sensor” combat-management system interface, which is the first of its kind to be deployed on Navy ships because it simply publishes data anyone can pick up. This makes it unnecessary to “redo” interfaces, according to Ottaviano.

The main achievement of Block 2 was the creation of an open architecture with open signal processing. “We’ve moved away from custom processing, which was common in many military systems during the ‘80s, ‘90s, and 2000s,” Ottaviano says. “Now, the government and industry are embracing open architectures. The programmability it enables allows us to deal with threats – whether it’s an FPGA or signals intelligence work. So we’re seeing a shift from custom processors to off-the-shelf processors, which gives us the next level of flexibility to literally be able to reprogram on-the-fly in real time during engagement.”

Block 2 brings processing capability improvements

Processing capabilities are improving and enabling operations in real time that weren’t possible three years ago.

“Now, we can reprogram the front end of a system in real time, and we’re seeing the ability to inject RF into FPGAs directly,” Ottaviano explains. “This is an exciting capability that opens up all kinds of new options. The amount of processing power we can bring to bear continues to improve, and the tools are finally catching up. As the tools improve, we’re able to better manage its development.” This is a huge step forward, because everyone jumped into open architectures before the tools were really ready.

There’s also “a big effort going into general-purpose (GP) computation on GPUs, which are even more programmable and open in some ways than FPGAs,” he adds. “It now takes mere seconds to upgrade a system, as opposed to 30 seconds.”

Biggest Block 2 challenges

The front-end analog-to-digital conversion market was the biggest challenge, according to Ottaviano.

“As threats widened, it became the focal point. We keep moving the ‘choke point’ of the system closer to the front end,” he explains. “Ultimately, the front-end analog-to-digital conversion is the next thing we’re working to conquer.”

Why? It’s the “limiting factor to how open the front end can be, how wide the system can be at any one given point in time,” Ottaviano says. “So we’re working toward widening bandwidths, while maintaining the signal quality that everyone needs. Until recently, the challenge was that the commercial market drove the analog-to-digital devices.”

Overcoming obsolescence concerns with Block 2

As you can imagine, obsolescence of parts and components is a major concern during these types of upgrades. “It’s the beautiful double-edged sword of COTS,” notes Ottaviano. “A typical refresh cycle can be as short as 12 months, so shifting to COTS does present a challenge. While we’ve experienced obsolete parts, we haven’t missed a beat.”

Lockheed Martin saw the COTS challenges coming and has worked to manage it because of the savings COTS can bring. “But there’s a lot of downstream work to manage obsolescence, in terms of needing tighter integration with your supply base,” Ottaviano says.

Significantly, Block 2 is the first COTS electronic warfare system to be built. “It was a growing pain when we first started moving electronic warfare into COTS four to five years ago,” he admits. “But it’s a uniquely COTS system with key ingredients to hold it together.”

While COTS components may not exactly be known for being as reliable as custom ones, SEWIP is “performing very well out at sea in a harsh environment, proving that Blocks 1 and 2 can indeed be achieved using COTS components,” Ottaviano points out. One of the key requirements was a “processing board with 25-year reliability to ensure operation within uncooled environments,” he says. “This makes it crucial to work with suppliers who deliver high-reliability parts; you can’t deliver a fragile system.”

Testing SEWIP

The U.S. Navy is testing out a version of the Surface Electronic Warfare Improvement Project (SEWIP) on its littoral combat ship USS Freedom (Figure 1).


Figure 1: Testing of SEWIP is being done on the USS Freedom littoral combat ship. Photo courtesy of Lockheed Martin.

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The electronic warfare system enables USS Freedom and other naval ships to detect, classify, and prevent electromagnetic interference to thwart hostile forces from jamming the ship’s ability to use radar, communications, or weapons.

Lockheed Martin scaled the SEWIP – within eight months – to operate on both the Freedom and Independence class littoral combat ships to improve their defensive capabilities by enabling the ships to detect targets not seen by other sensors.

Blocks 3 and 4

Block 3 involves electronic-attack capability improvements and, as you’d suspect, is mostly classified. Earlier this year, Northrop Grumman (Falls Church, Virginia; was awarded a $267 million contract by the Navy to develop and manufacture the next-generation surface electronic warfare system.

The goal of Block 3 is to enhance Raytheon’s AN/SLQ-32 electronic warfare attack system through a series of upgrades that add new technologies and capabilities for early detection, signal analysis, threat warning, and protection from anti-ship missiles (Figure 2).


Figure 2: Lockheed Martin and Raytheon experts demonstrated an early Block 3 version of SEWIP during the multinational Rim of the Pacific (RIMPAC) maritime exercise near Hawaii in 2012. Photo courtesy of Lockheed Martin.

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It will feature “active and passive arrays” to perform electronic warfare and communications functions with continuous 360-degree coverage, according to Northrop Grumman. The solution is designed to interface with the ship’s combat management system, while multimission technology provides “unprecedented situational awareness” to effectively detect, track, and engage threats in high-clutter environments.

Block 4 is a future upgrade that will roll in an electro-optic or infrared approach to the spectrum, because threats are expanding to encompass more of the spectrum.

“Blocks 3 and 4 will both build upon Block 2 capabilities to provide more sensor data to that type of interface,” Ottaviano says. “Once these are fully rocked out, they’ll continue to be future-proofed against all of the threats that are emerging now, including the RF and infrared spectrum. This requires a solid understanding of the RF and signal environment and how to work within it better than your adversaries.”

Say, for example, that a new threat comes online; the sensors are easily upgraded. “The only thing you’d need to do is a simple software update, perhaps, and most of it is dealt with through quick parameter changes, so it’s software-defined and done in real time,” he adds. “The system sees new threats and figures out how to deal with them.” Perhaps best of all, it can be reprogrammed on the fly to help keep the fleet or planes out of harm’s way.


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