Mode S Section Supervisor - Joe Pagano - Phone: (609) 485-6238- Fax: (609) 485-6488

About the Mode S

The Mode S is a secondary surveillance and communication system which supports Air Traffic Control (ATC). Each Mode S transponder equipped aircraft is assigned a unique address code. Using this unique code, interrogations can be directed to a particular aircraft and replies can be unambiguously identified. Mode S limits its interrogations to specific targets, and proper timing of interrogations permits replies from closely spaced aircraft to be received without mutual interference. Mode S also provides monopulse detection for improved azimuth accuracy and includes RMM capabilities.

The Mode S also interrogates and receives aircraft position and altitude information from Air Traffic Control Radar Beacon System (ATCRBS) transponder equipped aircraft. As a back-up, the Mode S has the capability to operate as an Air Traffic Control Beacon Interrogator (ATCBI). As of the end of 1998, there are approximately 1 Mode-S sensors commissioned in the backup mode (IBI) with 141 of those fully commissioned in Mode-S.

The Beacon Video Reconstitutor (BVR) is an independent, self-contained unit designed to operate as part of the Mode S, ASR 7/8, ARTS IIA/IIE configuration. The BVR regenerates ATCRBS beacon video for ARTS IIA/IIE reply processing and Radar Alphanumeric Display Subsystem (RADS) presentation. The reconstituted beacon video is based on input from the Mode S.