WSF_CHAFF_WEAPON

weapon WSF_CHAFF_WEAPON

Script Class: WsfChaffWeapon

weapon <name> WSF_CHAFF_WEAPON
   ... Platform Part Commands ...
   ... Articulated Part Commands ...
   ... WSF_EXPLICIT_WEAPON Commands ...

   ejector <name>
      ... Chaff Ejector Commands ...
   end_ejector

   ... additional ejector definitions

   cloud_update_interval ...
   draw_cloud_approximations ...
   launched_platform_type ...

end_weapon

Overview

WSF_CHAFF_WEAPON represents a weapon that dispenses chaff parcels, consisting of a large number of shorted tuned dipole antennas cut to lengths designed to create a desired RCS response across a frequency range of interest. One or more dispensed chaff parcels combine to form a chaff cloud, which is generally used as a radar countermeasure in either corridor-laying or self-protection mode.

A chaff cloud is not a simulation entity, only an aggregation of parcels used to calculate a bistatic presented area to the interacting transmitter and receiver.

A chaff weapon is a WSF_EXPLICIT_WEAPON that creates parcels (each modeled as individual platforms) dispensed by a system of one or more ejectors. Each ejector is given a unique name and can be independently configured to specify quantity and type of parcels, location on the platform, and ejection velocity.

Commands

cloud_update_interval <time-value>

If non-zero, specifies a periodic time interval at which the simulation will update the state (position, velocity, size, etc.) of dispensed chaff parcels. If zero, parcels will only be updated when necessary to determine their state. See update_interval for movers.

Default: 0.0

draw_cloud_approximations <boolean-value>

If true, will use WsfDraw to draw an ellipsoid representing cloud approximations for debugging purposes. Can be used to visualize the presented area of the cloud used in RCS calculations.

Default: false

launched_platform_type <string-reference>

Although required in WSF_EXPLICIT_WEAPON this command is optional for WSF_CHAFF_WEAPON. Can be specified to add user-defined scripts to dispensed parcels, or other custom platform commands. However, it is an error to define a mover or radar_signature on this platform type, since these components are modeled internally to the simulation.

Default: If none is specified, a dummy WSF_PLATFORM type will be used.

Chaff Ejector Commands

quantity <integer-value>

Specifies the number of parcels that are initially available in the ejector.

Default: 10

parcel_type <string-reference>

Specifies the type of chaff parcel that this ejector dispenses. The specified value must represent a valid parcel type that must be defined when this ejector is initialized in the simulation.

Default: No default. Must be specified.

location <x length-value> <y length-value> <z length-value> <length-units>

Specifies the location of the ejector in the entity coordinate system of the dispensing platform.

Default: 0 0 0 meters

ejection_velocity <speed-value>
ejection_elevation <angle-value>
ejection_azimuth <angle-value>

Specifies the magnitude, azimuth, and elevation of the vector in the entity coordinate system that represents the additional velocity, relative to the dispensing platform, provided by the launching mechanism. Similar to launch_delta_v except specified in spherical rather than cartesian coordinates.

Default: 15.0 m/s, 0.0 deg, 0.0 deg