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An Active Electronically Scanned Array (AESA), also known as active phased array radar is a revolutionary type of radar whose transmitter and receiver functions are composed of numerous small transmit/receive (T/R) modules. AESA radars feature short to instantaneous (millisecond) scanning rates and have a desirable low probability of intercept.
Being immobile, AESA radars have vastly simpler mechanical designs. They require no complex hydraulics for antenna movement nor hinge appendages that are prone to failure. The AESA radar occupies less space than typical radar, because of its lesser infrastructure requirements and of course its absent range of motion. The distributed transmit function also eliminates the most common single-point failure mode seen in a conventional radar. With these improvements, maintenance crews are far less severely taxed, and the radar is much more reliable.
Main advantages over mechanically scanned arrays are extremely fast scanning rate, much higher range, tremendous number of targets being tracked and engaged (multiple agile beams), low probability of intercept, ability to function as a radio/jammer, simultaneous air and ground modes, Synthetic Aperture Radar.
Mechanical steering may be added to AESA radars for increased radar field of view; The movement performance of the antenna would not need to be nearly as great as that of a traditional radar, as the radar sweep is not integral to the contact update rate.
The difference between AESA and PESA
In a passive electronically scanned array (PESA), the microwave feed network in the back of the antenna is powered by a single RF source (magnetron, klystron, TWT, etc.), sending its waves into phase shift modules (usually digitally-controlled), which, in turn, feed the numerous emitting elements.
An AESA, instead, has an individual RF source for each of its many transmit/receive elements, making them "active".
This provides for a graceful degradation, so that many T/R modules may fail and the radar would not stop functioning.
Furthermore, AESA radars do not have an RF source in the common meaning of the term (magnetron\klystron\TWT), which usually requires extremely high operating voltages (reaching 50 kVa). Instead of any of the aforementioned traditional RF sources, individual AESA elements create electromagnetic waves through such objects as gallium-arsenide modules which usually require no more than 40 to 60 volts.
List of AESA radars
Airborne systems
- Northrop Grumman/Raytheon AN/APG-77, for the F-22 Raptor
- Northrop Grumman/Raytheon AN/APG-80, for the F-16E/F Block 60 Fighting Falcon
- Northrop Grumman/Raytheon AN/APG-81, for the F-35 Joint Strike Fighter
- Northrop Grumman Multi-role AESA, for the Boeing Wedgetail (AEW&C)
- Raytheon AN/APG-63(V)2 and AN/APG-63(V)3, for the F-15C Eagle
- Raytheon AN/APG-79, for the F/A-18E/F Super Hornet
- Raytheon AN/APQ-181 (AESA upgrade currently in development), for the B-2 Spirit bomber
- AMSAR, from the European GTDAR consortium, for Eurofighter and Rafale fighters
- SELEX Seaspray 7000E, for helicopters
- IAI Phalcon AEW&C Elta radar system
- Mitsubishi Electric Corporation AESA for the Mitsubishi F-2 fighter
- Ericsson Erieye AEW&C and NORA AESA for JAS-39 Gripen
- Phazotron Zhuk-A
Ground and sea-based systems
- APAR multi-function radar, primary sensor of Dutch De Zeven Provinciën and German Sachsen class frigates
- Israel Aircraft Industries EL/M-2080 "Green Pine" ground-based early warning AESA radar
- AN/SPY-3 multi-function radar for U.S. DD(X), CG(X) and CVN-21 next-generation surface vessels
- Raytheon U.S. National Missile Defense X-Band Radar (XBR)
- SAMPSON multi-function radar for U.K. Type 45 destroyers
See also
External links
- Active Electronically Steered Arrays – A Maturing Technology
- FLUG REVUE December 1998: Modern fighter radar technology
Active Electronically Scanned Array | Фазированная антенная решётка | 電子掃描陣列雷達
"Active Electronically Scanned Array"