# ARTS built-in documentation server

## Workspace Method antenna_responseGaussianConstant

### Description

Sets up a Gaussian antenna response, with no frequency variation.
The method assumes that the response is the same for all
frequencies and polarisations, and that it can be modelled
as Gaussian. The width of the Gaussian is specified by its
full width at half maximum (FWHM).
The grid generated has *grid_npoints* equidistant values, with
the first one at -grid_width/2 and the last one at grid_width/2.
If *grid_width* is set to <= 0, a default of twice the FWMH is
applied. This gives a coverage of about 98% of the response.
The default for *grid_npoints* is 21. When the grid width is 2*FWHM,
that default value gives an error < 0.001 of the integrated response
using trapezoidal integration. *grid_npoints* must be > 1.
If the 2D option is selected (*do_2d*), a circular antenna is
assumed. The same grid and FWHM is applied in both dimensions.
If the grid has a sufficiently high width the integral of the
response is 1. Otherwise the integral is smaller than 1. That
is, no normalisation is applied.

**Authors: **Patrick Eriksson

### Synopsis

antenna_responseGaussianConstant( | antenna_response, fwhm, grid_width, grid_npoints, do_2d ) |

### Variables

OUT | antenna_response | (GriddedField4) | The antenna pattern/response. |

GIN | fwhm | (Numeric) | Full width at half-maximum of the Gaussian function. |

GIN | grid_width | (Numeric, Default: -1.0) | Full width of grid (negative value gives 2*fwhm). |

GIN | grid_npoints | (Index, Default: 21) | Number of points to represent the grid, see above. |

GIN | do_2d | (Index, Default: 0) | Set to 1 to create a 2D antenna pattern. |