measurement_sensorGaussianFrequencyGrid

Workspace.measurement_sensorGaussianFrequencyGrid(self, measurement_sensor: pyarts.arts.ArrayOfSensorObsel | None = None, frequency_grid: pyarts.arts.AscendingGrid | None = None, f0_fwhm: pyarts.arts.ArrayOfVector2 | None = None, weight_cutoff: pyarts.arts.Numeric | None = None, pos: pyarts.arts.Vector3 | None = None, los: pyarts.arts.Vector2 | None = None, pol: pyarts.arts.Stokvec | None = None) → None

Sets a sensor with a Gaussian channel opening on a fixed frequency grid

Each element has a frequency grid, a single polarization and a single pair of positions and line-of-sight. The frequency grid may only consist of elements that are in the input frequency grid.

The Gaussian distribution by each element is defined by the f0_fwhm list of Vector2 values. In each Vector2, the first value is the frequency center (\(f_0\)) and the second value is the full width at half maximum (\(\sigma\)). The frequency center must be positive. The half maximum width must be non-negative, where a zero value means that the channel is just the dirac delta function at the frequency center, which then must be in frequency_grid.

The freqeuncy grid of each channel is cut when \(\exp\left(-0.5 \left[\frac{f - f_0}{\sigma}\right]^2\right)\) is less than the value of weight_cutoff. Note that this means channels might end of with zero frequency points.

The resulting vector of sensor elements can be considered exhaustive by future calculations if an only if the weight cutoff is non-positive and all half width half maximums are positive. Otherwise the vector is not exhaustive.

Author(s): Richard Larsson

Parameters:

  • measurement_sensor (ArrayOfSensorObsel, optional) – A list of sensor elements. See measurement_sensor, defaults to self.measurement_sensor [OUT]

  • frequency_grid (AscendingGrid, optional) – The discrete frequency grid. See frequency_grid, defaults to self.frequency_grid [IN]

  • f0_fwhm (ArrayOfVector2) – List of [f0, fwhm]. [IN]

  • weight_cutoff (Numeric, optional) – The weight cutoff. Defaults to 0.001 [IN]

  • pos (Vector3) – A position [alt, lat, lon]. [IN]

  • los (Vector2) – A line of sight [zenith, azimuth]. [IN]

  • pol (Stokvec, optional) – The polarization whos dot-product with the spectral radiance becomes the measurement. Defaults to 1 0 0 0 [IN]