University of California, Santa Cruz
Fundamentals of Timing and Synchronization with Applications to Accelerators
Russell Wilcox, Lawrence Berkeley National Laboratory and John D. Fox, SLAC/Stanford University
Purpose and Audience
This course is intended for accelerator physicists, operators and electrical engineers who are interested in the design of timing systems and synchronization techniques for particle accelerators. The course will focus on measurement and control of electromagnetic waves in transmission lines or waveguides, whether RF/microwave or optical. These systems are important in the distribution of phase reference information in accelerating systems, and also must include diagnostic techniques to measure beams with respect to RF signals.
Prerequisites
The course should be accessible to those with undergraduate exposure to electromagnetics, optics and electronics.
Objectives
This course will consist of two parts: an introduction to measurement and control of EM wave propagation methods and technology, followed by examples of timing and synchronization systems and beam timing diagnostic systems for accelerator purposes. Students will learn concepts and techniques that apply equally to EM waves in the RF, microwave and optical domains, as well as differences in their technical implementation. The course will enable students to understand how precise timing signals are transmitted and used in state-of-the-art practical systems.
Instructional Method
The course will consist of lectures and lab exercises. There will be laboratory sessions with microwave and optical sources, transmission lines, measurement instruments and methods of control, including CW and modelocked lasers, fiber optics, optical modulators, high speed detectors, spectrum analyzers (both optical and RF), and network analyzers. The labs will provide the opportunity to learn about devices methods discussed in the lectures.
Course Content
Fundamental concepts relating to time in EM wave propagation will be developed, including group and phase velocity, polarization, and time and frequency domain descriptions. Processing and control techniques such as phase and amplitude modulation, heterodyning and amplification will be presented, with attention to uncertainty and noise leading to timing uncertainty. The course assumes some familiarity with circuit fundamentals, and will cover EM wave fundamentals, optical waves and waveguides, photodetection, interferometers, laser fundamentals, optical coherence, and key RF and fiber optic components (e.g. directional couplers, modulators, harmonic generation, polarization controllers, mixers, amplifiers, and filters). Phase-locked loop control circuits will be discussed, including hybrid microwave/optical loops. The course will stress the complementary time-domain and frequency-domain descriptions of these circuit elements and behavior.
The second portion of this class will examine the system implementations of timing distribution in accelerators and light sources. These will include RF phase distribution to accelerator cavities, synchronization of pulsed lasers in photoinjectors and experiments, and time references for beam diagnostics. Techniques to measure beam timing information will be discussed. Related applications in areas such as synchronization of communications channels (e.g. TDMA channels) and distribution of phase coherent microwave LO signals for interferometric radio astronomy will be discussed to illustrate multiple applications of these techniques.
Reading Requirements
A collection of papers from the optical, microwave and accelerator literature will be provided. Other references include “Lightwave Technology: Telecommunication Systems ” by Govind P. Agrawal, Wiley-Interscience Publishers (2005) and “Fields and Waves in Communication Electronics" by Simon Ramo, John R. Whinnery and Theodore Van Duzer, Wiley Publishers (1994).
Credit Requirements
Students will be evaluated on performance as follows: final exam (40%), homework (30%), lab sessions (30%).