The Avionic system of the F-22 Raptor is highly different in comparison to the Avionics of other Fighter aircraft. The F-22 is equipped with highly integrated avionics, which all work unlike on conventional aircraft as one, to provide 360° situational awareness, this gives a pilot a clear edge over its adversaries.
The F-22 is capable of functioning as a "mini-AWACS." Though reduced in capability compared to dedicated airframes such as the E-3 Sentry, as with its threat identification capability, the F-22's forward presence is often of benefit. The system allows the F-22 to designate targets for cooperating F-15s and F-16s, and even determine if two friendly aircraft are targeting the same enemy aircraft, thus enabling one of them to choose a different target. It is often able to identify targets hundreds of times faster than accompanying dedicated AWACS.
The APG-77 by Northtrop Grumman is the Active Electronnically Scanned Array Radar monted on the F-22, it is used on the F-22 since the year 2000. One of it´s special features is the Low Probability of Being Intercepted mode (LPI) mode, to allow it to change frequencies 1000 times per second to reduce the chance of being intercepted by Radar Warning receivers, to maximise stealth. The APG-77v1 is made of over 2000 transmit/receive moduls and it´s range against a 1 m² target is up to 400 km . The capabilities and range of the APG-77 are unsurpassed by any other Radar.
The AN/ALR-94 is the passive receiver system, made by BAE systems, capable of detecting the radar signals in the environment. Composed of more than 30 antennae smoothly blended into the wings and fuselage, it is described by the former head of the F-22 program at Lockheed Martin Tom Burbage as "the most technically complex piece of equipment on the aircraft." With greater range (250+ nmi) than the APG-77 AESA radar, it enables the F-22 to limit its own radar emission which might otherwise compromise its stealth. As the target approaches, AN/ALR-94 can cue the AN/APG-77 radar to keep track of its motion with a narrow beam, which can be as focused as 2° by 2° in azimuth and elevation, furthermore the ALR-94 is able to comunicate with the APG-77, allowing the F-22 to lock on targets without using the radar, making it even stealthier.
The AN/AAR-56 is a defense system only monted on the F-22 Raptor, it allows the F-22 long range detection of airborne and surface launched threats. Lockheed Martin is still continuing to advance threat warning systems, developing high-resolution and multi-spectral sensor variants with expanded algorithm base that incorporates situational awareness and defensive infrared search and track against airborne targets, so that one day the F-22 will be able to use the AAR-56 as a IRST sensor against aerial targets.
The AN/ALE-52 is the F-22 Raptor´s countermeasure flare despenser, developed by BAE sytems. It uses conventional flares agianst IR-missiles like MJU-7 and MJU-10, as well as the especially for the F-22 developed MJU-39/40 countermeasures, against radar guided missiles RR-170 and RR-180 Chaff can be used. The Countermeasures can be launched by the pilot or by the AN/AAR-56 or ALR-94.