Class ALcdASTERIXTransformationProvider

java.lang.Object
com.luciad.format.asterix.ALcdASTERIXTransformationProvider

public abstract class ALcdASTERIXTransformationProvider extends Object
Provides the transformations needed to convert ASTERIX coordinates to WGS_84 lon/lat coordinates. Some ASTERIX categories use a local coordinate system, locations are for example specified relative to the radar location, but that radar location is not present in the data. Furthermore the details of how these coordinates need to be interpreted (the exact definition of the grid reference) is radar dependent. This provider allows to implement a transformation specific per radar system and per data category.

Note that this class is not used for ASTERIX category 240 (radar video). To correctly georeference category 240 data, see ALcdASTERIXReferenceProvider.

  • Constructor Details

    • ALcdASTERIXTransformationProvider

      public ALcdASTERIXTransformationProvider()
  • Method Details

    • provideModelModelTransformation

      public abstract ILcdModelModelTransformation provideModelModelTransformation(int aSacSic, ILcdModel aModel, Object aObject)
      Returns the transformation used to convert ASTERIX coordinates to WGS_84 lon/lat coordinates. The source and destination references must be set to the ILcdModelModelTransformation return by the implementation of this method.

      The source reference of the returned ILcdModelModelTransformation should be the reference representing the ASTERIX coordinate system. This can be different per category:

      CategoryCoordinate system
      1Grid coordinates relative to the radar
      30Grid coordinates relative to the radar
      48Grid coordinates relative to the radar
      62Grid coordinates relative to the radar
      Please refer to the asterix specifications for details about the used coordinate systems (www.eurocontrol.int/asterix).

      Note that in a future version new categories might be added that use a different coordinate system.

      The destination reference of the provided ILcdModelModelTransformation should be WGS 84, e.g. new TLcdGeodeticReference( new TLcdGeodeticDatum() ).

      This method should perform very fast, as it is invoked frequently.

      Parameters:
      aSacSic - The System Area Code (SAC) and System Identification Code (SIC) defining which surveillance system (radar) is used. Bits 9 to 16 represent the SAC code, the geographical area. The lower 8 bits represent the SIC code, the identification of a surveillance system within the given SAC. An overview of available SAC codes can be retrieved from www.eurocontrol.int/asterix.
      aModel - The model. Can for example be used to retrieve the user application profile, using aModel.getModelDescriptor and casting to ALcdASTERIXModelDescriptor.
      aObject - The domain object, e.g. a trajectory, a track, ... Can be used to retrieve specific information needed to provide the transformation.
      Returns:
      The transformation for the given parameters. The value must not be null: a default value must be returned for unknown parameters.