A low‐cost multi‐channel software‐defined radio‐based NMR spectrometer and ultra‐affordable digital pulse programmer

• Published in: Concepts in magnetic resonance. Part B, Magnetic resonance engineering Vol. 48B; no. 3
• Main Author: Michal, Carl A.
• Format: Journal Article
• Language: English
• Published: Hoboken John Wiley & Sons, Inc 01.07.2018
• Subjects: arduino; double‐resonance; Firmware; LimeSDR; Line spectra; Microcontrollers; NMR; Nuclear magnetic resonance; quadrature receiver; Software radio; Spectrum analysis; Synchronism; vector modulator
• ISSN: 1552-5031; 1552-504X
• DOI: 10.1002/cmr.b.21401

In recent years, a new generation of software‐defined radio (SDR) products has emerged that are well suited for adaptation for NMR instrumentation. The software and hardware of a new NMR spectrometer console based upon an inexpensive SDR product are described. This device is provided with open‐source firmware and drivers which have allowed the customization of its behavior and optimization for use in NMR. In particular, these low‐level modifications have allowed for straightforward synchronization of multiple SDR boards with each other and with other devices. Control of other devices is facilitated by a new digital pulse programmer constructed using an inexpensive open‐source, widely available microcontroller platform. The strategy used for precise, reproducible synchronization of the different components is described in detail. Representative spectra are presented demonstrating both high‐resolution and wide‐line spectroscopy with spectral widths up to 50 MHz.