Abstract: A field programmable gate array (FPGA)-based method is proposed to generate B₀ signals, with high accuracy, on magnetic resonance imaging (MRI) spectrometers. The FPGA reads the waveform data and external parameters, and stores them in the dual-port random access memory (RAM) and parameter registers, respectively. The B₀ signals are then generated using the pre-emphasis algorithm, and different time or amplitude parameters give different B₀ signals. The B₀ signals are collected by high speed acquisition card, and the least squares fitting algorithm is used to test the accuracy of the B₀ signals generated. The performance of this method was validated by experiments.

Key words: magnetic resonance imaging (MRI), spectrometer, B₀ signals, field programmable gate array (FPGA), data acquisition card