Automatic phase calibration for RF cavities using beam-loading signals
Precise calibration of the cavity phase signals is necessary for the operation of any particle accelerator. For many systems this requires human in the loop adjustments based on measurements of the beam parameters downstream. Some recent work has developed a scheme for the calibration of the cavity phase using beam measurements and beam-loading however this scheme is still a multi-step process that requires heavy automation or human in the loop. In this paper we analyze a new scheme that uses only RF signals reacting to beam-loading to calculate the phase of the beam relative to the cavity. This technique could be used in slow control loops to provide real-time adjustment of the cavity phase calibration without human intervention thereby increasing the stability and reliability of the accelerator.
Transient Beam Loading Based Calibration for Cavity Phase and Amplitude Setting
Traditional phase scan method for cavity phase and amplitude setting is offline and hard to track the variations of environment and operation points. An alternative beam loading based calibration method is investigated in this paper, which might become useful online/real time calibration method.
Development of FPGA-based Predistortion-type Linearization Algorithms for Klystrons within Digital LLRF Control Systems for ILC-like Electron Accelerators
The feedback gain is proportional to the klystron output amplitude characteristic. Close to operation the gain decreases and makes control difficult or even impossible. This situation can be overcome by the implementation of a klystron linearization, which linearizes the klystron output and keeps the control gain constant up to the point of saturation. In the following the development of predistortion-type FPGA-based linearization algorithms is described [3]. Introduction