public abstract class ALcdASTERIXReferenceProvider
Provides the model references for ASTERIX categories which are not decoded
as WGS84 lon/lat coordinates. Some ASTERIX categories are for example specified
relative to the radar location, but that radar location is not present in the
data. Furthermore the details of how the data needs to be interpreted (the exact
definition of the grid reference) is radar dependent. This provider allows to
assign a model reference to such data.
At the moment, this class is only used for ASTERIX category 240 (radar video).
For other categories, see ALcdASTERIXTransformationProvider.
TLcdASTERIXReferenceProvider is a default implementation
of this class which can be used for static radar platforms.
Returns the model reference in which the ASTERIX data is expressed. The returned
reference should describe grid coordinates relative to the radar (e.g. using an
azimuthal equidistant projection with the origin on the radar's position). In
other words, the model reference implicitly defines the position and orientation
of the radar platform.
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.
aDescriptor - The model descriptor of the model for which a reference is being
requested. Can for example be used to retrieve the user application
aObject - Domain object contained in the model for which a reference is being requested.
a model reference that encapsulates the position and orientation of the radar platform