MICA

Mode S interrogator code allocation

A coordinated network approach to interrogator code allocation for Mode S radar.

At EUROCONTROL, we ensure a coordinated network approach to interrogator code allocation for Mode S radars. This is necessary due to the limited number of Mode S interrogator codes (IC).

Legal basis

The requirements for the coordinated allocation and use of Mode S interrogator codes for the single European sky are laid down in European Commission Regulation (EC) No 262/2009. 

Tools

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 our Mode S interrogator code allocation web application (MICA). In addition, we have developed a System map generator and extractor tool (SMGET) to help you configure the surveillance and lockout coverage for a stand-alone Mode S interrogator or set of Mode S interrogators operating in a cluster. Learn more about our tools below.

SMGET

System map generator and extractor tool

MICA web

Mode S interrogator code allocation web application

Background

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

In order to avoid ambiguity in operating the system, it is essential that each Mode S radar be 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.

As the number of Interrogator Codes is limited, a centralised IC allocation system has been established for 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 managed by EUROCONTROL Network Manager’s SCC Unit on behalf of ICAO’s EUR regional office. We also support ICAO’s Middle East regional office in Mode S IC Allocation coordination for the ICAO Middle East Region. Interrogator code allocation requests for this region have to be submitted through the MID ICAO regional office. The stakeholder working arrangement is SGEG/MICOG.