Linear phase microstrip radio frequency transmit coils

摘要

Systems, devices and methods provide an RF coil which produces a field having linear phase variation across an imaging volume. In one embodiment, a coil comprises multiple microstrip elements configured to have an increased effective electrical length. This increase in electrical length allows for a larger linear phase shifts over the length of the microstrip element which in turn increases linear phase variation capabilities. This may be accomplished by increasing the effective dielectric properties of the microstrip element. Increasing the effective dielectric may be accomplished by utilizing distributed capacitors along the length of a microstrip element (e.g. lumped element capacitors), by altering the materials used to fabricate the microstrip element, etc. Additionally, increasing the effective dielectric may be accomplished using a combination of these means. Embodiments may further enable linear phase variation along the imaging volume at high frequencies, such as frequencies utilized for 3 T and above MRI devices.

主权项

1. A system comprising:
a main magnetic element configured to produce a magnetic field within a target volume; a radio frequency (RF) transmission coil configured to provide an RF pulse to the target volume which acts on the magnetic field, the RF transmission coil comprising:
a plurality of microstrip elements, wherein the plurality of microstrip elements are configured to generate transverse magnetic fields having substantially uniform amplitude and linear phase variation across the target volume; anda receiving coil separate from the transmission coil, the receiving coil configured to receive signals propagating from the target volume, wherein the plurality of microstrip elements are configured to provide a non-resonant travelling wave medium.