Data provided by ATS ANSP

The data format supplied by ATS ANSPs can be one of the following ASTERIX types:

• ASTERIX CAT048
• ASTERIX CAT062

The EMADDC team has a strong preference to receive ASTERIX CAT048 over ASTERIX CAT062. The reason being the lower resolution of the MACH number in ASTERIX CAT62 which in turn reduces the quality of the derived Temperature. EMADDC can process both ASTERIX formats.

Since December 2024, EMADDC, through KNMI, has been connected to the European NewPENS network. Several ANSPs are providing real-time data to KNMI via NewPENS using UDP unicast. NewPENS is the preferred method for EMADDC to receive data from ANSPs.

If only ASTERIX CAT062 data can be provided, EMADDC requests that the Mach number is also supplied at a higher resolution (0.001) within CAT062 I062/380 subfield #4. Additionally, the EMADDC team would like to inquire about the interpolation method(s) used by the radar tracker and for wich parameters., as interpolation between raw observations can often result in reduced quality of the derived meteorological data. EMADDC also needs to eliminate redundant data when the Aircraft Derived Data (I062/380) does not contain new information, based on the data age indicators in I062/295. Consequently, CAT062 typically delivers approximately 30% of the valuable data compared to CAT048.

For both formats the fields below are normally filled by ATS and decoded by the EMADDC software.

To populate these fields, BDS 2.0 (Aircraft Registration), BDS 4.0, BDS 5.0, and BDS 6.0 must be queried accordingly. Due to limitations in Europe regarding overinterrogation, EMADDC recognizes that not all registers are interrogated during every radar cycle. Therefore, EMADDC requires at least one, preferably multiple, radar revolutions during which all necessary BDS registers are interrogated to ensure the highest quality meteorological observations with minimal delays between register interrogations. If available, BDS 4.4 MRAR reports are also requested and processed by EMADDC. Data should be provided in real-time via NewPENS starting from Q4 2024.

Before EMADDC can process ASTERIX data the EMADDC processing requires radar detail information to calculate the position of the aircraft observations. For that reason the EMADDC team requests data suppliers to provide a file containing the following information of each radar present in the data provided:

• Radar SAC (System Area Code)
• Radar SIC (System Identification Code)
• Radar Latitude
• Radar Longitude
• Radar Elevation (including radar height) above MSL

The tables below show the possible content of the data for CAT048 and CAT 062.