Mode S Interrogator Code (IC) Allocation Cell

Whilst traditional Mode A/C Secondary Surveillance Radar stations continuously interrogate all aircraft within their range, Mode S Secondary Surveillance Radar stations establish addressed interrogations with aircraft within their coverage.

In order to avoid ambiguity in the operation of the system it is essential that each Mode S radar is allocated an Interrogator Code (IC) which, in a coordinated operational environment, protects its operation from interference with other Mode S radars operating in overlapping or contiguous airspace.

Due to the limited number of Interrogator Codes, it is necessary to have a centralised IC allocation system to ensure an optimised coordinated approach to the allocation and implementation of the ICs used by Mode S radars.

In the ICAO European region, the centralised IC allocation system is conducted by EUROCONTROL on behalf of the European regional office of ICAO.

EUROCONTROL is also supporting the Middle East regional office of ICAO in Mode S IC Allocation coordination of the ICAO Middle East Region. IC allocation requests for this region must be submitted through MID ICAO regional office.

The Commission of the European Union has adopted Regulation (EC) No 262/2009 of 30 March 2009 laying down requirements for the coordinated allocation and use of Mode S interrogator codes for the single European sky.

The process applicable to the allocation of Mode S Interrogator Codes in the ICAO European region and to the Interrogator Code conflict management is supported by a specific tool identified as “MICA web”. This web application is the dedicated place to submit IC applications in order to request an IC for a Mode S radar, and to retrieve corresponding issued IC allocations. Once the user is registered, the MICA web is accessible from the Eurocontrol OneSkyOnline portal.

Registered users may access the MICA web via the following link:

MICA web application

IC applications have to be submitted through the MICA web. Should access to the MICA web be unavailable, then an IC application may be submitted by e-mail. The Mode S IC application form can be downloaded from the following link. A completed copy should be emailed to us.

The Surveillance library contains a number of documents describing the processes and principles behind Mode S Interrogator Codes, the allocation process and application form.

For more information on MICA activities please contact us via email or visit MICA - Mode S Interrogator Code Allocation.

MICA Support

Contact us for information on MICA activities and support.