MRI RF Design (sigpy.mri.rf)¶

This MRI submodule contains functions and classes for MRI pulse design.

It contains functions to design a variety of RF pulses for MRI, such as SLR, adiabatic, parallel transmit, multibanded, and others. The submodule also includes other functions to assist with pulse design, such as I/O functions, trajectory/gradient designers, and Bloch simulators.

Explore RF design tutorials at sigpy-rf-tutorials. These are primarily Jupyter Notebooks, and provide more detailed instruction on pulse design workflow and function use.

See in-progress features at sigpy-rf.

Adiabatic Pulse Design Functions¶

`sigpy.mri.rf.adiabatic.bir4`	Design a BIR-4 adiabatic pulse.
`sigpy.mri.rf.adiabatic.hypsec`	Design a hyperbolic secant adiabatic pulse.
`sigpy.mri.rf.adiabatic.wurst`	Design a WURST (wideband, uniform rate, smooth truncation) adiabatic
`sigpy.mri.rf.adiabatic.goia_wurst`	Design a GOIA (gradient offset independent adiabaticity) WURST
`sigpy.mri.rf.adiabatic.bloch_siegert_fm`	U-shaped FM waveform for adiabatic Bloch-Siegert \(B_1^{+}\) mapping and spatial encoding.

B1-Selective Pulse Design Functions¶

`sigpy.mri.rf.b1sel.dz_b1_rf`	Design a \(B_1^{+}\)-selective excitation pulse following Grissom JMR 2014
`sigpy.mri.rf.b1sel.dz_b1_gslider_rf`	Design a \(B_1^{+}\)-selective excitation gSlider pulse following
`sigpy.mri.rf.b1sel.dz_b1_hadamard_rf`	Design a \(B_1^{+}\)-selective Hadamard-encoded pulse following Grissom JMR 2014.

RF Linear Operators¶

sigpy.mri.rf.linop.PtxSpatialExplicit Explicit spatial-domain pulse design linear operator.

Pulse Multibanding Functions¶

`sigpy.mri.rf.multiband.mb_rf`	Multiband an input RF pulse.
`sigpy.mri.rf.multiband.dz_pins`	PINS multiband pulse design.

Optimal Control Design Functions¶

`sigpy.mri.rf.optcont.blochsim`	1D RF pulse simulation, with simultaneous RF + gradient rotations.
`sigpy.mri.rf.optcont.deriv`	1D RF pulse simulation, with simultaneous RF + gradient rotations.

Parallel Transmit Pulse Designers¶

`sigpy.mri.rf.ptx.stspa`	Small tip spatial domain method for multicoil parallel excitation.
`sigpy.mri.rf.ptx.stspk`	Small tip spokes parallel transmit pulse designer.

RF Shimming Functions¶

`sigpy.mri.rf.shim.calc_shims`	RF shim designer.
`sigpy.mri.rf.shim.init_optimal_spectral`	Function to return initial shim weights based on an optimal spectral method, an eigenvector-based method.
`sigpy.mri.rf.shim.init_circ_polar`	Function to return circularly polarized initial shim weights.

RF Pulse Simulation¶

`sigpy.mri.rf.sim.abrm`	1D RF pulse simulation, with simultaneous RF + gradient rotations.
`sigpy.mri.rf.sim.abrm_nd`	N-dim RF pulse simulation
`sigpy.mri.rf.sim.abrm_hp`	1D RF pulse simulation, with non-simultaneous RF + gradient rotations.
`sigpy.mri.rf.sim.abrm_ptx`	N-dim RF pulse simulation

SLR Pulse Design Functions¶

`sigpy.mri.rf.slr.dzrf`	Primary function for design of pulses using the SLR algorithm.
`sigpy.mri.rf.slr.root_flip`	Exhaustive root-flip pattern search for min-peak b1
`sigpy.mri.rf.slr.dz_gslider_rf`	Design a g-slider pulse rf
`sigpy.mri.rf.slr.dz_gslider_b`	Design a g-slider pulse b
`sigpy.mri.rf.slr.dz_hadamard_b`	Design a pulse with hadamard encoding
`sigpy.mri.rf.slr.dz_recursive_rf`	Recursive SLR pulse design.

Trajectory and Gradient Design Functions¶

`sigpy.mri.rf.trajgrad.min_trap_grad`	Minimal duration trapezoidal gradient designer.
`sigpy.mri.rf.trajgrad.trap_grad`	General trapezoidal gradient designer for total target area (for rewinders)
`sigpy.mri.rf.trajgrad.spiral_varden`	Variable density spiral designer.
`sigpy.mri.rf.trajgrad.spiral_arch`	Analytic Archimedean spiral designer.
`sigpy.mri.rf.trajgrad.epi`	Basic EPI single-shot trajectory designer.
`sigpy.mri.rf.trajgrad.rosette`	Basic rosette trajectory designer.
`sigpy.mri.rf.trajgrad.stack_of`	Function for creating a 3D stack of ____ trajectory from a 2D [Nt 2] trajectory.
`sigpy.mri.rf.trajgrad.spokes_grad`	Spokes gradient designer.
`sigpy.mri.rf.traj_complex_to_array`	Function to convert complex convention trajectory to [Nt 2] trajectory
`sigpy.mri.rf.traj_array_to_complex`	Function to convert [Nt 2] convention traj to complex convention
`sigpy.mri.rf.min_time_gradient`	Given a k-space trajectory c(n), gradient and slew constraints.

RF Utility¶

sigpy.mri.rf.util.dinf Calculate D infinity for a linear phase filter.

I/O¶

`sigpy.mri.rf.io.siemens_rf`	Write a .pta text file for Siemens PulseTool.
`sigpy.mri.rf.io.signa`	Write a binary waveform in the GE format.
`sigpy.mri.rf.io.ge_rf_params`	Calculate RF pulse parameters for deployment on a GE scanner.
`sigpy.mri.rf.io.philips_rf_params`	Calculate RF pulse parameters for deployment on a Philips scanner.