HELIOS Satellite

The , also know as the Heliosat, is a multipurpose UNSC Satellite for providing battlefield support to ground forces. The primary role of the HELIOS is that of a spy satellite. Using it's powerful optical telescope, infra-red telescope and weather piercing ground reading Synthetic Aperture RADAR, based on a adaptable and steerable AESA system, the HEIOS can observe a wide ground area with a high degree of accuracy. Through its onboard CPU, it can determine the type of unit on the ground, observe it's movement and relay it's information onto the War Net. It can even detect and discern the armament and equipment of the unit and detect units with optical camouflage. 
It's secondary purpose is as a GPS satellite, providing a global position system over the battlefield, allowing units to use GPS guidance for movement, for plotting courses and deploying ordnance. To this end, it also works as a communications satellite, allowing ground units to converse with units far out of their range by bouncing signals off the satellite. 
The HELIOS is driven by a powerful logic engine, that can put some older generation A.I.s to shame and has full cyber protection, through a advanced array of attack and dummy barriers, shared by most UNSC satellites.