Sea-SLQ-32
The US Navy’s AN/SLQ-32 is being cycled through several upgrades being performed by a number of firms which will ensure that this 20th century hardware can meet the challenge posed by 21st century threats.

What do seminal Mancunian post-punk doyens Joy Division and the US Navy’s Raytheon AN/SLQ-32 naval electronic warfare system have in common?

They both debuted in 1979. Joy Division released their ‘Unknown Pleasures’ album; a genre-defining tour-de-force in stripped-down rock while the ‘Slick-32’, as the system is nicknamed by the US Navy and which sounds like one of the band’s song titles, began its installation on the fleet’s surface ships.

US Navy’s Raytheon AN/SLQ-32

The intervening 40 years saw Joy Division morph into electro pioneers New Order following the death of their lead singer Ian Curtis on 15 May 1980. The AN/SLQ-32 is similarly going strong but like its musical counterpart, in a noticeably different form from its original design.

The baseline AN/SLQ-32(V)1 covered wavebands between five gigahertz/MHz and 20 gigahertz/GHz in terms of signals detection. This was later expanded downwards to 250MHz for the AN/SLQ-32(V)2/3/4 incarnations regarding signals interception.

In its original form the AN/SLQ-32 generated decoy waveforms designed to fool the radar seeker of an incoming Anti-Ship Missile (AShM) vis-à-vis the location of the ship under attack. The AN/SLQ-32 is also linked to a ship’s soft-kill countermeasures launcher to dispatch chaff and RF (Radio Frequency) decoys.

AN/SLQ-32 configurations

The AN/SLQ-32 has been cycled through several distinct configurations over the years. For example, the AN/SLQ-32(V)2 contains additional antennas and electronics to detect threats emitting across Very/Ultra High Frequency (V/UHF) wavebands of 250MHz to three gigahertz and can provide early warning as well as the identification of incoming threats.

The AN/SLQ-32(V)3 configuration added the jamming capability to engage threats transmitting across a 5GHz to 20GHz waveband. The AN/SLQ-32(V)3 which followed was an AN/SLQ-32(V)4 configuration designed for aircraft carriers, while the AN/SLQ-32(V)5 was a jamming module added to the AN/SLQ-32(V)1/2 to enable these systems to perform electronic attack.

SEWIP

An overarching modernisation known as the Surface Electronic Warfare Improvement Programme (SEWIP) for the US Navy’s AN/SLQ-32(V) systems commenced in 2002, with an initial contract (Block-1) for the upgrade awarded to General Dynamics one year later.

This effort mainly addressed obsolescence issues in the legacy hardware and software of deployed AN/SLQ-32(V)s. Lockheed Martin was then awarded an initial contract to outfit the AN/SLQ-32(V) with a high gain, high sensitivity antenna under the SEWIP Block-1B3 initiative. This improves the amount of jamming power that the AN/SLQ-32(V) can direct against a target, and its sensitivity to incoming radar signals.

Lockheed Martin won a second SEWIP contract (SEWIP Block-2) in 2009 which transitioned existing AN/SLQ-32(V) systems to the AN/SLQ-32(V)6 status when teamed with the SEWIP Block-1B3 modification.

The firm is continuing the Full Rate Production (FRP) of the AN/SLQ-32(V)6 covering 71 systems which it expects to complete in 2020, a Lockheed Martin spokesperson told Armada Analysis. A further five years of AN/SLQ-32(V)6 production is on the horizon, the spokesperson continued, following the signature of a second FRP contract with the company on 27 January. This will see AN/SLQ-32(V)6 production continuing until 2024, the spokesperson added.

SEWIP Block-3 contract

The SEWIP Block-3 contract was awarded to Northrop Grumman in 2015 with the intention of widening the waveband covered by the equipment.

As noted above, the AN/SLQ-32(V) in its original form covered frequencies of 250MHhz/5GHz to 20GHz. Although no details have been released, this may have now increased to circa 40GHz.

This would be vital in allowing the system to detect, and possibly attack, radar-guided AShMs transmitting in Millimetre Wave (MMW) frequencies of 30GHz and above.

MMW is increasingly popular as such short wavelengths allow a radar to discern a target with a high level of detail. This improves accuracy and countermeasures rejection as the radar can separate the target from chaff or active RF decoys.

The Islamic Republic of Iran’s Kowsar AShM series is thought to use a MMW radar seeker transmitting in Ka-band (33.4GHz to 36GHz). This missile type may have been fired from the coast of Lebanon by cadres from the Hezbollah Shia Islamist movement against the Israeli Navy’s ‘Sa’ar-5’ class corvette INS Hanit causing the death of four sailors on 14 July 2006.

AN/SLQ-32(V) systems upgraded to Block-3 will be re-designated AN/SLQ-32(V)7. Over the long term, a Block-4 enhancement is planned which could see optronics and infrared technology being added to the AN/SLQ-32(V) architecture to further improve AShM detection and tracking.

by Dr. Thomas Withington