ICALEPCS1991 - Classification: Timing and Synchronization

Paper	Title	Page
S10TS01	Realtime Aspects of Pulse-to-Pulse Modulation	345
	R. Steiner, C. Riedel, W. Rösch GSI, Darmstadt, Germany
	The pulse-to-pulse modulation of the SIS-ESR control system is described. Fast response to operator interaction and to changes in process conditions is emphasized as well as the essential part played by the timing system in pulse-to-pulse modulation. The benefits of pulse-to-pulse modulation in acceleration operating have been described as early as ’77 for the CERN’s PS complex. It is an effective way to increase the overall output of valuable beamtime of one or more accelerators. With beamsharing, rarely all users of the beam will be unable to accept the beam at the same time. If the PPM-handling quickly responds to changing conditions, there will be virtually no dead-time in the machine operating due to inevitable dead-times of experiments, e.g. during new experimental setups. In a multi-accelerator facility, PPM is almost imperative. Asynchronously running machines, every one of them operating as an injector for the next one, normally have time left between subsequent injections that can be used for experiments.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS01
About •	Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

S10TS02	Injection Timing System for PLS	349
	S.-S. Chang, S.J. Choi, M.S. Kim, W. Namkung, S.Y. Park, S.C. Won PAL, Pohang, Republic of Korea
	The ultimate goal of the PLS timing system is to successfully inject a electron bunch to a predesigned bucket in the Storage Ring. In the Linac, a pretrigger of 10².8 microseconds prior to the Gun trigger may be required to charge the pulsed divces properly and it should be precisely delayed to synchronize with beam pass at each accelerating column. To inject the electron bunch, which fully accelerated in the Linac, into a target bucket of SR, the injection kicker magnets must be energized to provide the appropriate magnetic field. For the sequential filling of the SR buckets, the appropriate timing delays throughout the entire timing system are programmable controlled by operator.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS02
About •	Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

S10TS03	Automated Control System Structure of the USSR Academy of Sciences Kaon Facility	352
	Yu.S. Ivanov, L.L. Filipchicov, V.A. Konovalov, B.P. Murin MRI, Moscow, Russia S.K. Esin, Y. Senichev RAS/INR, Moscow, Russia
	Up to date at Nuclear Research Institute of the USSR AS (Moscow-Troitsk) it is finished building of Moscow Meson Facility high intensity current proton Linear Accelerator (LA) (beam parameters: energy - 600 MeV, average current - 0.5 mA, pulse current - 50 mA). The LA is proposed to serve as Kaon Facility (KF) which is under working out. There are presented brief description of the KF system.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS03
About •	Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

S10TS04	The Development of RF Reference Lines and a Timing System for Japan Linear Collider	356
	J. Urakawa, S. Araki, T. Kawamoto, T. Mimashi, Y. Otake, Y. Satoh KEK, Ibaraki, Japan
	The main linac of Japan Linear Collider(JLC) will be operated at an X-band frequency of 11.424 GHz. The positioning of the X-band accelerating structures at JLG requires precise phase synchronisation over about 10 km. Temperature compensated fiber optic cables will be used for the transmission of the 11.424 GHz RF signal. The performance of this transmission line is described. Many timing signals will be also transmitted from the main control room, in which the master RF frequency generator will be situated, via this l.3 ¿m single mode fiber optic link. The outline of the timing system for JLC is given in this paper.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS04
About •	Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

S10TS05	A New VME Timing Module: TG8	360
	C.G. Beetham, G. Daems, J.H. Lewis, B. Puccio CERN, Geneva, Switzerland
	The two accelerator divisions of CERN, namely PS and SL, are defining a new common control system based on PC, VME and Workstations. This has provided an opportunity to review both central timing systems and to come up with common solutions. The result was, amongst others, the design of a unique timing module, called TG8. The TG8 is a multipurpose VME module, which receives messages distributed over a timing network. These messages include timing information, clock plus calendar and telegrams instructing the CERN accelerators on the characteristics of the next beam to be produced. The TG8 compares incoming messages with up to 256 programmed actions. An action consists of two parts, a trigger which matches an incoming message and what to do when the match occurs. The latter part may optionally create an output pulse on one of the eight output channels and/or a bus interrupt, both with programmable delay and telegram conditioning.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS05
About •	Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

S10TS06	Modular Pulse Sequencing in a Tokamak System	364
	A.C. Chew, S. Lee, S.H. Saw Plasma Research Laboratory, University of Malaya, Kuala Lumpur, Malaysia
	Pulse technique applied in the timing and sequencing of the various part of the MUT tokamak system are discussed. The modular architecture of the pulse generating device highlights the versatile application of the simple physical concepts in precise and complicated research experiment. In experimental studies of pulse plasma devices, timing and sequencing of the various events are an important part of the experiment and requires careful considerations. This is achieved in the MUT (University of Malaya Tokamak) tokamak system by employing modular architecture involving various modules of pulse generating devices.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS06
About •	Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

S10TS07	The Timing System of the RFX Nuclear Fusion Experiment	367
	V. Schmidt, G. Flor, G. Manduchi, I. Piacentini Consorzio RFX, Associazione Euratom-ENEA sulla Fusione, Padova, Italy V. Schmidt HMI, Berlin, Germany
	The RFX Nuclear Fusion Experiment in Padova, Italy, employs a distributed system to produce precision trigger signals for the fast control of the experiment and for the experiment-wide synchronization of data acquisition channels. The hardware of the system is based on a set of CAMAC modules. The modules have been integrated into a hardware/software system which provides the following features: # generation of pre-programmed timing events, # distribution of asynchronous (not pre-programmed) timing events, # gating of timing event generation by Machine Protection System, # automatic stop of timing sequence in case of highway damage, # dual-speed timebase for transient recorders, # system-wide precision of ¿3 ¿s, time resolution ¿ l0 ¿s. The operation of the timing system is fully integrated into the RFX data acquisition system software. The Timing System Software consists of three layers: the lowest one corresponds directly to the CAMAC modules, the intermediate one provides pseudo-devices which essentially correspond to specific features of the modules (e.g. a dual frequency clock source for transient recorders), the highest level provides system set-up support. The system is fully operational and was first used during the commissioning of the RFX Power Supplies in spring ’91.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS07
About •	Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

S10TS08	An Optical Fiber Phase Lock Network of a Radio Interferometer	371
	M. Nishio, S. Kawashima, H. Nakajima, C. Torii NAO-NRO, Minamisaku, Nagano, Japan N. Futagawa, K. Nishikawa, T. Takabayashi Space and Laser Communication Development Division, NEC Corporation, Yokohama, Japan S. Tanaka Sumitomo Electric Industries Ltd., Yokohama Laboratory, Yakohama, Japan
	A new phase-lock network using fiber-optic system was developed as a local signal distribution system for 84 antennas of the Nobeyama Radioheliograph. This network is an open loop system and consists of a master oscillator with an E/O converter, an 1-to-84 optical divider, phase stable optical fiber cables and phase stable phase-locked oscillators with O/E converters. Phase stability of the network and phase noise generated at the O/E converter are discussed. This phase-lock network insures the required phase stability of 3°/6 hours. The phase noise increases the coherent loss of 0.1 % at the correlator output, which is very low. This is the first large application of fiber optic devices to an open loop phase-lock network. Our system is very simple and phase-stable. Therefore, it is suitable to the connected array with large number of antennas.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS08
About •	Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Realtime Aspects of Pulse-to-Pulse Modulation

345

R. Steiner, C. Riedel, W. Rösch
GSI, Darmstadt, Germany

The pulse-to-pulse modulation of the SIS-ESR control system is described. Fast response to operator interaction and to changes in process conditions is emphasized as well as the essential part played by the timing system in pulse-to-pulse modulation. The benefits of pulse-to-pulse modulation in acceleration operating have been described as early as ’77 for the CERN’s PS complex. It is an effective way to increase the overall output of valuable beamtime of one or more accelerators. With beamsharing, rarely all users of the beam will be unable to accept the beam at the same time. If the PPM-handling quickly responds to changing conditions, there will be virtually no dead-time in the machine operating due to inevitable dead-times of experiments, e.g. during new experimental setups. In a multi-accelerator facility, PPM is almost imperative. Asynchronously running machines, every one of them operating as an injector for the next one, normally have time left between subsequent injections that can be used for experiments.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS01

About •

Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

S10TS02

Injection Timing System for PLS

349

S.-S. Chang, S.J. Choi, M.S. Kim, W. Namkung, S.Y. Park, S.C. Won
PAL, Pohang, Republic of Korea

The ultimate goal of the PLS timing system is to successfully inject a electron bunch to a predesigned bucket in the Storage Ring. In the Linac, a pretrigger of 10².8 microseconds prior to the Gun trigger may be required to charge the pulsed divces properly and it should be precisely delayed to synchronize with beam pass at each accelerating column. To inject the electron bunch, which fully accelerated in the Linac, into a target bucket of SR, the injection kicker magnets must be energized to provide the appropriate magnetic field. For the sequential filling of the SR buckets, the appropriate timing delays throughout the entire timing system are programmable controlled by operator.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS02

About •

Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

S10TS03

Automated Control System Structure of the USSR Academy of Sciences Kaon Facility

352

Yu.S. Ivanov, L.L. Filipchicov, V.A. Konovalov, B.P. Murin
MRI, Moscow, Russia
S.K. Esin, Y. Senichev
RAS/INR, Moscow, Russia

Up to date at Nuclear Research Institute of the USSR AS (Moscow-Troitsk) it is finished building of Moscow Meson Facility high intensity current proton Linear Accelerator (LA) (beam parameters: energy - 600 MeV, average current - 0.5 mA, pulse current - 50 mA). The LA is proposed to serve as Kaon Facility (KF) which is under working out. There are presented brief description of the KF system.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS03

About •

Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

S10TS04

The Development of RF Reference Lines and a Timing System for Japan Linear Collider

356

J. Urakawa, S. Araki, T. Kawamoto, T. Mimashi, Y. Otake, Y. Satoh
KEK, Ibaraki, Japan

The main linac of Japan Linear Collider(JLC) will be operated at an X-band frequency of 11.424 GHz. The positioning of the X-band accelerating structures at JLG requires precise phase synchronisation over about 10 km. Temperature compensated fiber optic cables will be used for the transmission of the 11.424 GHz RF signal. The performance of this transmission line is described. Many timing signals will be also transmitted from the main control room, in which the master RF frequency generator will be situated, via this l.3 ¿m single mode fiber optic link. The outline of the timing system for JLC is given in this paper.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS04

About •

Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

S10TS05

A New VME Timing Module: TG8

360

C.G. Beetham, G. Daems, J.H. Lewis, B. Puccio
CERN, Geneva, Switzerland

The two accelerator divisions of CERN, namely PS and SL, are defining a new common control system based on PC, VME and Workstations. This has provided an opportunity to review both central timing systems and to come up with common solutions. The result was, amongst others, the design of a unique timing module, called TG8. The TG8 is a multipurpose VME module, which receives messages distributed over a timing network. These messages include timing information, clock plus calendar and telegrams instructing the CERN accelerators on the characteristics of the next beam to be produced. The TG8 compares incoming messages with up to 256 programmed actions. An action consists of two parts, a trigger which matches an incoming message and what to do when the match occurs. The latter part may optionally create an output pulse on one of the eight output channels and/or a bus interrupt, both with programmable delay and telegram conditioning.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS05

About •

Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

S10TS06

Modular Pulse Sequencing in a Tokamak System

364

A.C. Chew, S. Lee, S.H. Saw
Plasma Research Laboratory, University of Malaya, Kuala Lumpur, Malaysia

Pulse technique applied in the timing and sequencing of the various part of the MUT tokamak system are discussed. The modular architecture of the pulse generating device highlights the versatile application of the simple physical concepts in precise and complicated research experiment. In experimental studies of pulse plasma devices, timing and sequencing of the various events are an important part of the experiment and requires careful considerations. This is achieved in the MUT (University of Malaya Tokamak) tokamak system by employing modular architecture involving various modules of pulse generating devices.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS06

About •

Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

S10TS07

The Timing System of the RFX Nuclear Fusion Experiment

367

V. Schmidt, G. Flor, G. Manduchi, I. Piacentini
Consorzio RFX, Associazione Euratom-ENEA sulla Fusione, Padova, Italy
V. Schmidt
HMI, Berlin, Germany

The RFX Nuclear Fusion Experiment in Padova, Italy, employs a distributed system to produce precision trigger signals for the fast control of the experiment and for the experiment-wide synchronization of data acquisition channels. The hardware of the system is based on a set of CAMAC modules. The modules have been integrated into a hardware/software system which provides the following features: # generation of pre-programmed timing events, # distribution of asynchronous (not pre-programmed) timing events, # gating of timing event generation by Machine Protection System, # automatic stop of timing sequence in case of highway damage, # dual-speed timebase for transient recorders, # system-wide precision of ¿3 ¿s, time resolution ¿ l0 ¿s. The operation of the timing system is fully integrated into the RFX data acquisition system software. The Timing System Software consists of three layers: the lowest one corresponds directly to the CAMAC modules, the intermediate one provides pseudo-devices which essentially correspond to specific features of the modules (e.g. a dual frequency clock source for transient recorders), the highest level provides system set-up support. The system is fully operational and was first used during the commissioning of the RFX Power Supplies in spring ’91.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS07

About •

Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

S10TS08

An Optical Fiber Phase Lock Network of a Radio Interferometer

371

M. Nishio, S. Kawashima, H. Nakajima, C. Torii
NAO-NRO, Minamisaku, Nagano, Japan
N. Futagawa, K. Nishikawa, T. Takabayashi
Space and Laser Communication Development Division, NEC Corporation, Yokohama, Japan
S. Tanaka
Sumitomo Electric Industries Ltd., Yokohama Laboratory, Yakohama, Japan

A new phase-lock network using fiber-optic system was developed as a local signal distribution system for 84 antennas of the Nobeyama Radioheliograph. This network is an open loop system and consists of a master oscillator with an E/O converter, an 1-to-84 optical divider, phase stable optical fiber cables and phase stable phase-locked oscillators with O/E converters. Phase stability of the network and phase noise generated at the O/E converter are discussed. This phase-lock network insures the required phase stability of 3°/6 hours. The phase noise increases the coherent loss of 0.1 % at the correlator output, which is very low. This is the first large application of fiber optic devices to an open loop phase-lock network. Our system is very simple and phase-stable. Therefore, it is suitable to the connected array with large number of antennas.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS08

About •

Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)