You can save ASTERIX data to a file with the TLcdASTERIXFinalModelEncoder. This class is an implementation of ILcdModelEncoder. The model encoding documentation describes how you can use an ILcdModelEncoder.

This article outlines the possibilities and constraints of ASTERIX encoding.

Models accepted for ASTERIX encoding

The TLcdASTERIXFinalModelEncoder can only encode and save model lists or models produced by the TLcdASTERIXModelDecoder. This means that you cannot convert other formats, such as ESRI Shape files, to ASTERIX files.

These are examples of the encoding possibilities for decoded ASTERIX models:

  • You can decode an ASTERIX file that contains multiple categories. As a result, the TLcdASTERIXModelDecoder creates a model list with a model per category. You can then encode a model of a single category to a separate file.

  • You can set a TLcdASTERIXSacSicRecordFilter on the TLcdASTERIXModelDecoder, so that it only decodes the messages from one specific radar. When you encode the resulting model, the file will only contain the messages from the radar you specified.

Data changes saved by the ASTERIX encoder

Any changes that you make to the properties of tracks or trajectories are saved by the TLcdASTERIXFinalModelEncoder. This allows you to fill in information that was missing from the ASTERIX data. For instance, you can fill in the callsign of a trajectory for category 30. The encoder will save the changed callsign to the file it writes. The ASTERIX data decoding guide contains more information about the properties that can be changed, and about how you can change them. Keep in mind that you cannot change weather picture properties.

In addition, you can remove unwanted trajectories, plots, or weather pictures from the ILcdModel that you are encoding. The encoder will only save the information of the trajectories, plots and weather pictures that are present in the model.

As explained in the ASTERIX data decoding guide, the geometry and timing information of trajectories, plots, and weather pictures cannot be changed. This means that you cannot save a new ASTERIX file in which trajectories start or end at different times, or are positioned at a different location, for instance.

Data is saved in the ASTERIX final format

The ASTERIX data is encoded in the ASTERIX final format if the destination file ends with astfin. Otherwise the data is encoded in the raw ASTERIX format.

The ASTERIX final format is described in The ASTERIX Final format.