Alerting system for interrogator code conflicts: Romanian air navigation service provider deploys DFS technology

The Romanian Air Traffic Services Administration (ROMATSA) has put the Mode S Interrogator Code Conflict Alerter (MICCA) into operation. The application was developed by the German air navigation service provider (ANSP) DFS Deutsche Flugsicherung to identify interrogator code conflicts of Mode S radar stations. Such conflicts may result in aircraft not being fully detected by one or more Mode S sensors.

MICCA allows system monitoring staff to simultaneously overview interrogator code conflicts at all Mode S facilities, to quickly identify affected sensors and to analyse the conflicts. Reconfiguring the affected radar station is one of the possible solutions to such a problem.

This alerting system can process live radar data from up to 32 Mode S radar stations and displays target acquisition problems graphically in real time. For example, the number of conflicts for each Mode S sensor can be represented on a time axis. Another feature is the ability to show where aircraft experienced a delay in radar detection or where they were not detected at all. As soon as specific adjustable thresholds are reached, the system sets off a visual and audible alert.

DFS has been using this in-house development to monitor Mode S facilities since 2010. The Latvian ANSP Latvijas Gaisa Satiksme (LGS) has employed this DFS tool since 2013.

A European Commission regulation has been in place since 2009 that requires Mode S operators to implement monitoring means to detect interrogator code conflicts (Regulation 262/2009, Article 7).