High Power RF Pulse Shaping Tests with NG-LLRF and Cool Copper Collider Prototype Structure

TL;DR

This paper demonstrates high-power RF pulse shaping using a digital NG-LLRF system with a prototype collider structure, achieving precise control up to 5.4 MW and 1 microsecond pulses, enabling advanced accelerator applications.

Contribution

It introduces a fully digital RF pulse shaping method with the NG-LLRF platform, eliminating the need for additional analog components in high-power RF systems.

Findings

Achieved RF pulse shaping up to 5.4 MW peak power

Demonstrated pulse widths of about 1 microsecond

Validated the effectiveness of digital pulse shaping in high-power RF applications

Abstract

RF pulse modulation techniques are widely applied to shape RF pulses for various types of RF stations of particle accelerators. The amplitude and phase modulations are typically implemented with additional RF components that require drive or control electronics. For the RF system-on-chip (RFSoC) based next generation LLRF (NG-LLRF) platform, which we have developed in the last several years, RF modulation and demodulation are fully implemented in the digital domain. Therefore, arbitrary RF pulse shaping can be realized without any additional analogue components. We performed a range of high-power experiments with the NG-LLRF and a prototype Cool Copper Collider (C3) structure. In this paper, the RF field measured at different stages with different pulse shapes and peak power levels up to 5.4 MW and pulse width about 1 microsecond will be demonstrated and analyzed. The high precision pulse shaping schemes of the NG-LLRF can be applied to realize the phase modulation for a linear accelerator injector, the phase reversal for a pulse compressor, or the modulation required to compensate for the beam loading effect.