Coil

class pulserver.virtual.Coil

Bases: object

The RF coils of an exam, fixed in the physical frame: the coil pulses are transmitted on and the coil the signal is received by.

name is transmit/receive, or one coil’s name where it does both. Each side is BART’s coil model (HEAD_2D_8CH or HEAD_3D_64CH) and the number of its channels the coil takes, the first ones, as phantom -S selects them, or the file of the coil’s field maps coils() reads; a side without either is one channel of unit sensitivity everywhere, as a body coil is taken to be. A model is sampled by bartorch on first use, which the coils extra installs, over MODEL_FOV along the physical axes; HEAD_2D_8CH is constant along z. Either is interpolated linearly.

Receive sensitivities are scaled to a root sum of squares of 1 at the isocentre, and transmit sensitivities so that the default_shim plays a pulse at its nominal amplitude at the isocentre. A model’s transmit sensitivities are the complex conjugates of its receive sensitivities, the quasi-static limit of reciprocity.

Methods

limits	Return the VOP entries of the check limits a design is made under in this coil; none unless its transmit maps have VOPs beside them.
receive	Return each coil's receive sensitivity at (n, 3) physical points, in m: (n, coils); None for one uniform coil.
transmit	Return each channel's transmit sensitivity at (n, 3) physical points, in m: (n, channels); None for one uniform channel.

Attributes

default_shim	Unit channel weights that bring every transmit channel into phase at the isocentre; None for one channel.
receive_channels	Coils a readout is received by.
receive_model
transmit_channels	Channels a pulse is played on.
transmit_model
name