Raytheon forges ahead with AESA GAN upgrade for Patriot radar

Officials from Raytheon briefed MONch on the ongoing programme to upgrade the firm’s AN/MPQ-65A C-band (5.25 gigahertz/GHz to 5.925GHz) combined ground-based air surveillance and fire control radar with Gallium Nitride Active Electronically Scanned Array (GAN AESA) technology.

GAN offers significant benefits for radars principally the comparatively higher operating temperatures it can tolerate compared to the Gallium Arsenide (GAS) materials used to equip earlier generations of AESA radar. The higher operating temperatures of GAN translates into enhanced performance for radars in terms of range, target discrimination and the reduction of the radar’s overall maintenance, repair and overhaul burden. The AN/MPQ-65A forms a key part of Raytheon’s MIM-104 family of semi-active radar homing surface-to-air missile ensemble.

Raytheon is using GAN AESA technology to developed a three-faced version of the single-faced legacy AN/MPQ-65A radar which will provide staring 360 degree surveillance dispensing with the need to have a rotating single antenna to provide such coverage. Raytheon officials told MONch that they feel the application of staring 360 degree surveillance using GAN AESA architecture will offer significant benefits in detecting and tracking potential and actual airborne threats, with these capabilities particularly applicable to tracking and engaging multiple targets. The 360 degree capability for the radar, which is undergoing development, will be available as both a retrofit package for existing AN/MPQ-65A operators, as well as being procurable as a new build system. The company added that, for all intents and purposes, the rest of the digital architecture rolled out across the AN/MPQ-65A radar as a result of the MIM-104F Patriot Advanced Capability-3 upgrade will remain the same. Company representatives continued that it has already secured a customer for the AN/MPQ-65A equipped with the 360 degree surveillance capability in the form of Poland, although they disclosed that the rest of the MIM-104 Patriot customer base all have either existential, or expected future, requirements for ground-based air surveillance radars equipped with such a capability. The US Army is also a prospective customer for the AN/MPQ-64 360 degree capability for the US Army’s Lower Tier Air and Missile Defence System (LTAMDS) radar programme. Raytheon, together with Lockheed Martin and Northrop Grumman is currently completing a 15-month concept definition contract for the force regarding this requirement. The LTAMDS is intended to yield a radar which will replace the ‘vanilla’ version of the AN/MPQ-65A radar currently in service with the force equipping its MIM-104 batteries. According to media reports, the US Army is expected to perform an LTAMDS preliminary design review in 2020. The army has stated that GAN AESA architecture is one of the LTAMDS requirements.

Raytheon stated that its development work on the 360 degree capability is at the US government’s Material Readiness Level-8/9 (MRL-8/9) and Technology Readiness Level-6 (TRL-6). What this means in practice is that the product is ready to commence low rate production, with the ability to commence low rate production also demonstrated (MRL-8/9) and that the product has been demonstrated as a prototype in a relevant environment (TRL-6). Raytheon expects that it could deliver the fully-functional 360 degree surveillance capability to a customer within 48 months or less.

Thomas Withington