|Country of origin||United States|
|Type||Solid-state active electronically scanned array (AESA)|
|Power||20 kW peak|
It is a solid-state, active electronically scanned array (AESA) radar. Composed of 1956 transmit/receive modules, each about the size of a gum stick, it can perform a near-instantaneous beam steering (in the order of tens of nanoseconds).
The APG-77 provides 120° field of view in azimuth and elevation, which is the highest possible value for a flat phased array antenna. As yet unconfirmed sources suggest that APG-77 has a 'typical' operating range of 193 km (120 mi) and is specified to achieve an 86% probability of intercept against a 1 m2 target at its maximum detection range using a single radar paint. Other source described only as being more than 100 mi (160 km). However, it's thought to be closer to 125–150 mi (201–241 km), or even 400 km for newer GaaS modules on the APG-77v1, which is much farther than the standard F-15's original APG-63(v)1 56-mile (90 km) radar range 
More than one hundred APG-77 AESA radars have been produced to date by Northrop Grumman, and much of the technology developed for the APG-77 is being used in the APG-81 radar for the F-35 Lightning II.
The APG-77v1 was installed on F-22 Raptors from Lot 5 and on. This provided full air-to-ground functionality (high-resolution synthetic aperture radar mapping, ground moving target indication and track (GMTI/GMTT), automatic cueing and recognition, combat identification, and many other advanced features).
- Hfradar.pdf page 19 for number of modules[dead link][dead link]
- Physical limitation of the maximum swivel angle of an AESA
- Jane's Radar And Electronic Warfare Systems
- Aviation Week – Raptor Scores in Alaskan Exercise
- Northrop Successfully Completes F-22 Radar Flight-Test Certification