GNSS (Global Navigation Satellite Systems) play crucial geolocation, tracking, and navigation roles in defense. A GNSS is a radio-based system that employs satellite constellations to determine the position of an entity on earth accurately. One of the many uses of GNSS in the military is precise geolocation. These systems enable users to accurately locate enemy positions, friendly facilities, and other areas of interest. They also make it possible to identify the position of troops for operations such as search and rescue, providing backup or medical assistance, and mission planning. GNSS also serve in projectile and unmanned vehicle guidance. Another vital use of GNSS in the military is navigation. This includes land, sea, air, and subsea-based navigation. These systems are especially necessary when navigating through unfamiliar or hostile territory.