RFSoC Based LLRF System Design at ALS

Qiang Du; Shreeharshini Murthy; Victoria Moore; Angel Jurado Lopez; Michael Chin; Shree Subhasish Basak; David Nett; Benjamin Flugstad

arXiv · 2510.13192

RFSoC Based LLRF System Design at ALS

Qiang Du·Shreeharshini Murthy·Victoria Moore·Angel Jurado Lopez·Michael Chin·Shree Subhasish Basak·David Nett·Benjamin Flugstad

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Abstract

The Advanced Light Source (ALS) at LBNL is upgrading several LLRF systems for its Linac and Sub-Harmonic Bunchers, where it is desired to have a unified LLRF system design to support various RF frequencies (at 125MHz, 500MHz and 3GHz) and configurations. This paper demonstrates an open-source, direct sampling RFSoC based LLRF system design, featuring: sample-to-sample Multi-Tile Synchronization, deterministic latency, digital up/down conversion, arbitrary waveform generation and acquisition, in-pulse closed loop control, timing and EPICS integration, modular RF frontend and hardware designs. Measured RF characteristics show that the RFSoC based LLRF system is able to meet the system requirements.

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Qiang Du, Shreeharshini Murthy, Victoria Moore, Angel Jurado Lopez, Michael Chin, Shree Subhasish Basak, David Nett, Benjamin Flugstad. 2025-10-15. RFSoC Based LLRF System Design at ALS. https://arxiv.org/abs/2510.13192

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