def _beam_map_single(self, bl_index, f_index):
p_stokes = [
0.5 * np.array([[1.0, 0.0], [0.0, 1.0]]),
0.5 * np.array([[1.0, 0.0], [0.0, -1.0]]),
0.5 * np.array([[0.0, 1.0], [1.0, 0.0]]),
0.5 * np.array([[0.0, -1.0J], [1.0J, 0.0]])
]
# Get beam maps for each feed.
feedi, feedj = self.uniquepairs[bl_index]
beami, beamj = self.beam(feedi, f_index), self.beam(feedj, f_index)
# Get baseline separation and fringe map.
uv = self.baselines[bl_index] / self.wavelengths[f_index]
fringe = visibility.fringe(self._angpos, self.zenith, uv)
pow_stokes = [
np.sum(beami * np.dot(beamj.conjugate(), polproj), axis=1) *
self._horizon for polproj in p_stokes
]
# Calculate the solid angle of each beam
pxarea = (4 * np.pi / beami.shape[0])
om_i = np.sum(np.abs(beami)**2 * self._horizon[:, np.newaxis]) * pxarea
om_j = np.sum(np.abs(beamj)**2 * self._horizon[:, np.newaxis]) * pxarea
omega_A = (om_i * om_j)**0.5
# Calculate the complex visibility transfer function
cv_stokes = [p * (2 * fringe / omega_A) for p in pow_stokes]
return cv_stokes
def _beam_map_single(self, bl_index, f_index):
p_stokes = [ 0.5 * np.array([[1.0, 0.0], [0.0, 1.0]]),
0.5 * np.array([[1.0, 0.0], [0.0, -1.0]]),
0.5 * np.array([[0.0, 1.0], [1.0, 0.0]]),
0.5 * np.array([[0.0, -1.0J], [1.0J, 0.0]]) ]
# Get beam maps for each feed.
feedi, feedj = self.uniquepairs[bl_index]
beami, beamj = self.beam(feedi, f_index), self.beam(feedj, f_index)
# Get baseline separation and fringe map.
uv = self.baselines[bl_index] / self.wavelengths[f_index]
fringe = visibility.fringe(self._angpos, self.zenith, uv)
pow_stokes = [ np.sum(beami * np.dot(beamj.conjugate(), polproj), axis=1) * self._horizon for polproj in p_stokes]
# Calculate the solid angle of each beam
pxarea = (4*np.pi / beami.shape[0])
om_i = np.sum(np.abs(beami)**2 * self._horizon[:, np.newaxis]) * pxarea
om_j = np.sum(np.abs(beamj)**2 * self._horizon[:, np.newaxis]) * pxarea
omega_A = (om_i * om_j)**0.5
# Calculate the complex visibility transfer function
cv_stokes = [ p * (2 * fringe / omega_A) for p in pow_stokes ]
return cv_stokes
def _beam_map_single(self, bl_index, f_index):
# Get beam maps for each feed.
feedi, feedj = self.uniquepairs[bl_index]
beami, beamj = self.beam(feedi, f_index), self.beam(feedj, f_index)
# Get baseline separation and fringe map.
uv = self.baselines[bl_index] / self.wavelengths[f_index]
fringe = visibility.fringe(self._angpos, self.zenith, uv)
pxarea = (4 * np.pi / beami.shape[0])
# Beam solid angle (integrate over beam^2 - equal area pixels)
om_i = np.sum(np.abs(beami)**2 * self._horizon) * pxarea
om_j = np.sum(np.abs(beamj)**2 * self._horizon) * pxarea
omega_A = (om_i * om_j)**0.5
# Calculate the complex visibility transfer function
cvis = self._horizon * fringe * beami * beamj.conjugate() / omega_A
return [ cvis ]
def _beam_map_single(self, bl_index, f_index):
# Get beam maps for each feed.
feedi, feedj = self.uniquepairs[bl_index]
beami, beamj = self.beam(feedi, f_index), self.beam(feedj, f_index)
# Get baseline separation and fringe map.
uv = self.baselines[bl_index] / self.wavelengths[f_index]
fringe = visibility.fringe(self._angpos, self.zenith, uv)
pxarea = (4 * np.pi / beami.shape[0])
# Beam solid angle (integrate over beam^2 - equal area pixels)
om_i = np.sum(np.abs(beami)**2 * self._horizon) * pxarea
om_j = np.sum(np.abs(beamj)**2 * self._horizon) * pxarea
omega_A = (om_i * om_j)**0.5
# Calculate the complex visibility transfer function
cvis = self._horizon * fringe * beami * beamj.conjugate() / omega_A
return [cvis]
