FPGA Controlled RF Pulse Generator for Teaching MRI
Abstract
Currently, many researchers in MRI are focused on creating low-cost MR setups using off-the-shelf components that are comparable in performance to existing MR systems. A problem these setups face is phase instability due to hardware components not synchronized perfectly. To overcome this, systems with pulse generation and echo digitization on a single hardware platform are gaining popularity.
With FPGAs gaining traction in recent years, it is unsurprising to find them being incorporated in low-cost MR setups today. This is because of their suitability in highly precise applications along with occupying smaller chip areas, consuming lesser power and keeping equipment cost lower than their analog counterparts. Given the current scenario of virtual and hybrid classes, FPGAs also make it possible to get hands-on experience in building working MR setups using off-the-shelf components at home, which promotes learning while being socially distant. Hardware platforms such as the Red Pitaya are well-suited for this purpose, which has an Artix-7 FPGA coupled with a dual-core ARM Cortex A9 processor, and DACs and ADCs all housed under the same chassis.
This thesis aims to build and test an RF pulse generator on an FPGA using a Red Pitaya board. The pulse generator is integrated into a tabletop MR setup and its phase stability determined using a Pentek high-speed digitizer. The entire process has been documented in a manual attached to this document along with all source codes used. Finally, a discussion has been initiated regarding the inclusion of a working digitizer within Pitaya itself, alongside the pulse generator.
Citation
Usmani, Mariam Nida (2021). FPGA Controlled RF Pulse Generator for Teaching MRI. Master's thesis, Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /196260.