Status of RF synchronization and fast trigger distribution

Reported by H. Damerau (CERN)

Acknowledgements: J. Moody, P. Muggli (MPP), D. Barrientos, T. Bohl, A. Butterworth, S. Doebert, W. Hofle, J. Molendijk, S. Rey,

D. Stellfeld, U. Wehrle (CERN)

19 August 2015

Simplified overview of AWAKE synchronization and RF distribution

Laser PLL

Fiber receiver/trans

mitter

3 GHz master

GPS receiver

Fiber receiver/trans

mitter

SPS synchro

crate

88.2 MHz (laser)2997.9 MHz(reference)

10 MHz (reference)

9.97 Hz, 8.68 kHz, 400.4 MHz, 10 MHz

Fractional divider

SPS

Main RF divider

400.4 MHz

Fast pulse triggers

Buffer amplifiers

ElectronLLRF

Various frequencies distributed (many!)

Fast pulse triggers (~20 adjustable)

Laser

Buffer amplifiers

Fast pulse triggers

176.3 MHz

Timing

Tim

ing200.2 MHz Proton LLRF

Extraction and bunch rotation triggers

BA4

TSG40 BA3/Faraday Cage

2

3

Laser phase locked loop and RF reference

1. Laser phase-locked loop2. 3 GHz low-noise reference oscillator3. GPS receiver for 10 MHz frequency reference

® Engineering specification draft prepared– https://

edms.cern.ch/file/1516886/1/2015-03-02_AWAKE_EngSpecTemplate_v0.0_LaserLockedLoop_draft2.pdf

– Feedback from potential supplier expected by end of this week

® GPS reference part of package, but could be acquired separately® Most probably also separate optical transmission from BA4 TSG40

with transmitter/receiver provided by CERN

4

New electronic designs

1. Receivers and transmitters for compensated fibre transmission (Diego, John, BE/RF/CS), LHC-type VME form factor

® Conceptual design and choices of components completed® Detailed electronics design progressing well

2. Main divider and fractional divider boards (Stephane, HD, BE/RF/FB), LHC-type VME form factor

® Conceptual design essentially frozen– https://edms.cern.ch/file/1516886/1/FrequenciesTimings3GHzReferencePhaseD

iscriminator_2015-04-24.pdf

® Electronics development can only start in September– Critical hardware, critical path for first prototype in early 2016

5

Synchronization with SPS

1. Synchronization crate (as for LHC) in BA3/Faraday Cage (Thomas, Urs, BE/RF/BR and BE/RF/FB)

® Decision to keep separate RF synchronization® Detailed layout of synchronization extraction process

– https://edms.cern.ch/file/1516892/1/ExtractionTimingsSPS-AWAKE_2012-07-13.pdf

– https://edms.cern.ch/document/1516892/1

® No new electronics development required– Status of spare modules to be checked and made operational– Possibly production run of some hardware

® Installation and commissioning expected this year (if boards available)

6

Cabling, crates, racks

1. Two special racks TSG40 (EN/EL and BE/RF FSU team)® Installed by EN/EL and BE/RF FSU team

2. RF distribution cabling® Completed (fully?) under supervision of Guillaume (EN/EL) many

thanks!

3. Optical fibers (TSG40 to BA3 and BA4)® Request submitted to Jeremy (EN/EL)® Separate fibers for GPS reference from BA4 during 2015/16 YETS

4. Special LHC-type VME crates (Donat, BE/RF/FB)® Crate in BA3/Faraday Cage installed® New production run including crates for AWAKE launched

7

RF distribution and fast trigger pulses

1. RF distribution® No new electronics development required

– Most probably production run of existing distribution buffers

2. Fast trigger pulse generation® One board per channel (~20 channels)® No new electronics development required

– Production run of existing VTU (or CTU) boards

® Compile detailed ‘shopping list’ of boards to be tested or reproduced (HD)