Jianyu Zhao

2020

1. J. Zhao, A. Mohamed, and J. Anders, “An Active CMOS NMR Field Probe with Custom Transceiver and ΣΔ Modulator ASICs and an Optical Link,” in 2020 IEEE International Symposium on Circuits and Systems (ISCAS), in 2020 IEEE International Symposium on Circuits and Systems (ISCAS). Oct. 2020, pp. 1–5. doi: 10.1109/ISCAS45731.2020.9181026.
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   BibTeX

   @inproceedings{9181026, abstract = {In this paper, we present a CMOS-based miniaturized magnetic resonance (MR) system for magnetic field and trajectory mapping incorporating an electromagnetic interference (EMI) robust optical link. The system consists of a custom-designed, CMOS-based active NMR field probe, a custom-designed, single-bit ΣΔ modulator and a commercial optical link. The low-IF architecture of the transceiver ASIC, reduces the required bandwidth in the digitizer to a few hundred kilohertz, enabling the use of a single-bit ΣΔ modulator, whose high frequency, one bit data stream is ideally suited for feeding the following optical link. The custom ΣΔ modulator uses a third order loop filter and employs a 12-tap FIR DAC to increase its robustness against clock jitter. It is manufactured in a 0.18 μm CMOS technology and achieves an SNDR of 72.19 dB over a Nyquist bandwidth of 800 kHz. In the proposed setup, the 1-bit output stream of the ΣΔ modulator directly feeds the driver of a commercial optical fiber link to transmit the NMR data from inside the NMR magnet to the remotely located digital signal processing unit with a very high robustness against EMI. In-situ NMR experiments with a 1.45 T benchtop magnet using a silicone sample demonstrate the very good performance of the overall system, achieving a frequency resolution of 12.6 Hz or 200 ppb in the estimation of the sample's NMR resonance frequency. This corresponds to an effective magnetic field resolution of 290 nT.}, author = {{Zhao}, J. and {Mohamed}, A. and {Anders}, J.}, booktitle = {2020 IEEE International Symposium on Circuits and Systems (ISCAS)}, doi = {10.1109/ISCAS45731.2020.9181026}, issn = {2158-1525}, month = {10}, pages = {1-5}, title = {An Active CMOS NMR Field Probe with Custom Transceiver and ΣΔ Modulator ASICs and an Optical Link}, url = {https://ieeexplore.ieee.org/document/9181026/}, year = 2020 }

   Link

   https://ieeexplore.ieee.org/document/9181026/

   DOI

   10.1109/ISCAS45731.2020.9181026