Bandlimited waveform designs: improving gradient waveform fidelity and controlling acoustic response

Motivation: MRI gradient waveforms with high slew rates and short durations have broad spectral content, challenging the limited bandwidth of gradient amplifiers. They can also produce loud acoustics, potentially exciting resonances in the audible range. Goal(s): We seek to design waveforms with improved fidelity and controlled acoustics by tailoring their spectral content. Approach: We propose a dual domain optimization problem for periodic waveforms with controls as Fourier series coefficients, allowing us to tailor the frequency response and ensure bandlimited waveforms. Results: The proposed structure results in small, sparse optimization problems. We demonstrate this with EPI readouts, improving waveform fidelity and controlling acoustic response. Impact: Short, high slew rate gradient waveforms improve scan efficiency but are loud and not fully realizable due to their frequency content. We propose a simple optimization problem for designing periodic waveforms like EPI trains, ensuring bandlimited waveforms with good fidelity.