:orphan: .. **************************************************************************** .. CUI .. .. The Advanced Framework for Simulation, Integration, and Modeling (AFSIM) .. .. The use, dissemination or disclosure of data in this file is subject to .. limitation or restriction. See accompanying README and LICENSE for details. .. **************************************************************************** radar_signature --------------- .. contents:: :local: .. command:: radar_signature ... end_radar_signature :block: .. parsed-literal:: radar_signature ** use_bisector_for_bistatic_ interpolate_tables_ interpolation_type_ [linear | logarithmic] state_ | default polarization_ [ horizontal | vertical | slant_45 | slant_135 | left_circular | right_circular | default ] frequency_limit_ ... :ref:`Azimuth-elevation_Table_Definition` ... frequency_limit_ ... :ref:`Azimuth-elevation_Table_Definition` ... polarization_ ... plt_file_ ... state_ ... end_radar_signature Overview ======== :command:`radar_signature` defines the radar signature for a platform type. The radar signature is used when a radar sensor attempts to detect a platform. The radar signature consists of one or more sets of tables where each set defines the signature (as a function of polarization and frequency) that applies when the platform is in a particular 'state.' A 'state' represents a condition such as 'bay-doors-open.' **** is the name to be given to the signature. If the name specifies the name of an existing definition then the new definition will replace the current one (i.e. the last occurrence will be used for the simulation.) Commands ======== .. command:: use_bisector_for_bistatic Specifies if a bistatic signature will be approximated for bistatic detection attempts. * If **true**, the RCS will be determined using the bisector of the target-to-transmitter and target-to-receiver aspect angles. * If **false**, the RCS will be determined using the target-to-receiver aspect angle. **Default** true .. command:: interpolate_tables Specifies whether to apply interpolation to the defined :ref:`Azimuth-elevation_Table_Definition`. The type of interpolation can be either linear or logarithmic (see interpolation_type_). **Default** true .. command:: interpolation_type Specifies whether to use linear or logarithmic interpolation when interpolating data in the azimuth elevation tables. **Default** linear .. command:: state [ | default ] Indicates that the following table definitions will be used when the platform is in the signature state **. If **default** is specified then the subsequent table(s) will be used if the platform is in a signature state that does not match any of the states defined in the signature. If a **state** command is not specified, then the signature has one set of tables that applies to all signature states. .. command:: polarization [ horizontal | vertical | slant_45 | slant_135 | left_circular | right_circular | default ] Indicates that the following table(s) (up to the next **polarization** or **state**) are to be used when the sensing radar is operating with the specified polarization. If **polarization** is omitted then the following table(s) (up to the next **state**) are applicable to any polarization. .. command:: frequency_limit Indicates the upper frequency bound to which the following table applies. These must occur in increasing order within a single state/polarization grouping. For a radar is operating with a particular polarization and frequency, the table selected will be the first one with the proper state and polarization where the frequency less than **frequency_limit**. If **frequency_limit** is omitted then the following table applies to all frequencies. .. command:: plt_file [default ] Loads a PLT file, in either 3- or 5-column format, that includes multiple Az/El table definitions indexed by polarization and frequency. Because the polarization and frequency are embedded within the file, any previous polarization_ or frequency_limit_ command will be ignored. Optionally, a polarization (horizontal or vertical) to be used as the default may be specified. However, since every state must have a **default** polarization, if this optional argument is omitted, one must be defined explicitly using the polarization_ command. .. note:: Only horizontal and vertical polarizations are currently accepted within the PLT file. .. note:: The frequencies specified in plt_files are center frequencies, not frequency limits. For an EM interaction at a specific frequency, the table will be chosen based on a frequency band about the center frequency, not based on frequency limits. For example,consider a a plt_file with frequency-indexed tables at 0.1, 1, and 10 GHz. In this case EM interactions between 0 and 0.55 GHz will use the first table, interactions between 0.55 and 5.5 GHz use the second table, and interactions at 5.5 GHz and above use the third table. Examples ======== Inline table:: radar_signature AIRPLANE_RADAR_SIG state default inline_table dbsm 20 2 -90.0 90.0 -180.0 0.0 0.0 -137.5 0.0 0.0 -135.0 20.0 20.0 -132.5 0.0 0.0 -92.5 0.0 0.0 -90.0 20.0 20.0 -87.5 0.0 0.0 -47.5 0.0 0.0 -45.0 20.0 20.0 -42.5 0.0 0.0 42.5 0.0 0.0 45.0 20.0 20.0 47.5 0.0 0.0 87.5 0.0 0.0 90.0 20.0 20.0 92.5 0.0 0.0 132.5 0.0 0.0 135.0 20.0 20.0 137.5 0.0 0.0 180.0 0.0 0.0 end_inline_table end_radar_signature .. include:: _radar_signature.wsf_mil.txt