NuRadioReco.modules.LOFAR.beamforming_utilities module
- NuRadioReco.modules.LOFAR.beamforming_utilities.mini_beamformer(fft_data, frequencies, positions, direction)[source]
Beamforms the spectra given the arrival direction and antenna positions. This function is a wrapper around the beamformer() function, which beamforms the spectra given the timedelay. Here we first calculate the geometric delays in the far field, based on the arrival direction.
- Parameters:
- fft_datanp.ndarray
The Fourier transformed time traces of all antennae, shaped as (nr_of_ant, nr_of_freq_samples)
- frequenciesnp.ndarray
The values of the frequencies samples, shaped as (nr_of_freq_samples,)
- positionsnp.ndarray
The position of antenna, shaped as (nr_of_ant, 3)
- directionnp.ndarray
The arrival direction in the sky, in cartesian coordinates, shape (3,)
- Returns:
- beamformednp.ndarray
The beamformed (ie summed) frequency spectrum
Notes
Adapted from PyCrTools hBeamformBlock
- NuRadioReco.modules.LOFAR.beamforming_utilities.beamformer(fft_data, frequencies, delays)[source]
Beamform the spectra according to the given delays, by phase shifting them according to the time delays and summing up the resulting spectra.
- Parameters:
- fft_datanp.ndarray
The Fourier transformed time traces of all antennae, shaped as (nr_of_ant, nr_of_freq_samples)
- frequenciesnp.ndarray
The values of the frequencies samples, shaped as (nr_of_freq_samples,)
- delaysnp.ndarray
The delay per antenna, shaped as (nr_of_ant,)
- Returns:
- beamformednp.ndarray
The beamformed (ie summed) frequency spectrum
- NuRadioReco.modules.LOFAR.beamforming_utilities.geometric_delays_near_field(ant_pos, sky)[source]
Calculate the geometric delays of given antenna position, given a source location in the sky.
- Parameters:
- ant_posarray_like
Antenna positions
- skyarray_like
Source location in the sky
- Returns:
- delaysarray_like
The geometric delays for all antenna positions.
- NuRadioReco.modules.LOFAR.beamforming_utilities.geometric_delay_far_field(ant_positions, direction)[source]
Calculate the geometric delays in the far field approximation, by projecting the positions onto the arrival direction vector and dividing by the lightspeed.
If the direction vector points towards the incoming direction (as usually calculated using zenith and azimuth), then positive delays correspond to later times compared to the [0, 0, 0] location.
- Parameters:
- ant_positionsarray_like
The positions of the antennae, with shape (nr_of_ant, 3)
- directionarray_like
The arrival direction, in cartesian coordinates