PointSpreadFunction¶

class
acoular.fbeamform.
PointSpreadFunction
¶ Bases:
traits.has_traits.HasPrivateTraits
The point spread function.
This class provides tools to calculate the PSF depending on the used microphone geometry, focus grid, flow environment, etc. The PSF is needed by several deconvolution algorithms to correct the aberrations when using simple delayandsum beamforming.

grid_indices
= CArray( dtype=int, value=array([]), desc="indices of grid points for psf") #value=array([]), value=self.grid.pos(),¶ Indices of grid points to calculate the PSF for.

mpos
= Trait(MicGeom, desc="microphone geometry")¶ MicGeom
object that provides the microphone locations.

env
= Trait(Environment(), Environment)¶ Environment
or derived object, which provides information about the sound propagation in the medium.

c
= Float(343., desc="speed of sound")¶ The speed of sound, defaults to 343 m/s

steer
= Trait('true level', 'true location', 'classic', 'inverse', desc="type of steering vectors used")¶ Type of steering vectors, see also Sarradj, 2012.

calcmode
= Trait('single', 'block', 'full', 'readonly', desc="mode of calculation / storage")¶ Flag that defines how to calculate and store the point spread function defaults to ‘single’.
 ‘full’: Calculate the full PSF (for all grid points) in one go (should be used if the PSF at all grid points is needed, as with
DAMAS
)  ‘single’: Calculate the PSF for the grid points defined by
grid_indices
, one by one (useful if not all PSFs are needed, as withCLEAN
)  ‘block’: Calculate the PSF for the grid points defined by
grid_indices
, in one go (useful if not all PSFs are needed, as withCLEAN
)  ‘readonly’: Do not attempt to calculate the PSF since it should already be cached (useful if multiple processes have to access the cache file)
 ‘full’: Calculate the full PSF (for all grid points) in one go (should be used if the PSF at all grid points is needed, as with

freq
= Float(1.0, desc="frequency")¶ Frequency to evaluate the PSF for; defaults to 1.0.

r0
= Property( desc="array center to grid distances")¶ Sound travel distances from microphone array center to grid points (readonly).

rm
= Property( desc="array to grid distances")¶ Sound travel distances from array microphones to grid points (readonly).

psf
= Property( desc="point spread function")¶ The actual point spread function.

precision
= Trait('float64', 'float32', desc="precision (32/64 Bit) of result, corresponding to numpy dtypes")¶ Floating point precision of property psf. Corresponding to numpy dtypes. Default = 64 Bit.
