Novel superconducting cyclotron tuning system

Abstract

The invention discloses a novel superconducting cyclotron tuning system. An analog IQ (in-phase and quadrature) phase detection module is used for modulating sine I and cosine Q of phase differences of LO (local oscillation) and RF (radio frequency) signals, and the modulated signals are used as input signals for an analog IQ phase detection calibration module; the analog IQ phase detection calibration module is used for calibrating measurement errors of the analog IQ phase detection module and provides real-time detection for the analog IQ phase detection module; after completing calibration,the analog IQ phase detection module is automatically turned off, and the influence of the analog IQ phase detection calibration module on analog IQ phase detection results is avoided. The combination technique of an analog signal processing system and a digital signal system is used herein, providing improved tuning precision and noise tolerance for the system and reduced time delay for a feedback system that is caused by signal processing; the analog IQ phase detection calibration module in the system of the invention provides improved self-adjusting capacity and extended applicable range for the analog IQ phase detection module.

Description

technical field [0001] The invention belongs to the technical field of cyclotrons, and in particular relates to a novel superconducting cyclotron tuning system. Background technique [0002] Superconducting cyclotrons are more and more widely used in medical fields such as PET (positron emission tomography) diagnosis, isotope production and proton therapy due to their unique compactness and low power consumption. Among them, the resonant cavity is one of the important parts of the superconducting cyclotron, and the resonant cavity mainly provides the electric field for ion acceleration. The working state of the resonator directly affects the beam quality. However, due to the electromagnetic thermal effect, mechanical vibration, beam load effect and other factors during the operation of the resonator, the resonator cannot operate stably in the specified working state, resulting in excessive reflected power of the power source and damage to the transmission system and power. ...

AI Technical Summary

Problems solved by technology

The analog tuning system was first applied to the tuning system control of the accelerator resonator, but due to the non-ideal factors of the analog device, the system has DC offset, phase imbalance and amplitude imbalance, so the pure analog tuning system is difficult. Meet higher control needs and precision

As DSP and FPGA have been widely used in control systems, more and more tuning control systems use digital signal processing systems. Digital signal processing systems can solve the problems of analog systems very well, but the delay of digital systems For the tuning control system with high control precision and low delay requirement, the digital system cannot meet the requirements, so there is a half-digital and half-analog tuning system, which can not only reduce the delay of the digital system, but also overcome the delay of the analog system. Disadvantages such as susceptibility to noise interference

The existing half-digital and half-analog tuning system can greatly improve the DC offset, phase imbalance, and amplitude imbalance of the analog tuning system to a certain extent. Noise, high precision, wide dynamic range and other demanding requirements, traditional calibration methods cannot meet the requirements

Images