What system does Mode S radar beacon support?

Mode S radar beacon primarily supports the Traffic Alert and Collision Avoidance System (TCAS). This system enhances flight safety by providing pilots with timely advisories about nearby aircraft that may pose a collision risk. Mode S technology enables TCAS to receive information directly from other Mode S equipped aircraft, enhancing situational awareness and improving the accuracy of the collision avoidance calculations.

This capability is crucial for maintaining safe distances between aircraft, especially in crowded airspace. Mode S beacons help identify the unique transponder codes of surrounding aircraft, allowing TCAS to process this information and generate alerts and advisories as necessary.

While other options like Automatic Dependent Surveillance-Broadcast (ADS-B) and various air traffic control communication systems exist and play essential roles in air traffic management, they do not rely specifically on the Mode S radar beacon for their primary functioning.