ivan procházka josef blažej, jan kodet presented at : elt meeting ctu in prague, december 8, 2010...
Post on 08-Jan-2018
217 Views
Preview:
DESCRIPTION
TRANSCRIPT
Ivan ProcházkaJosef Blažej, Jan Kodet
presented at :
ELT meeting CTU in Prague, December 8, 2010
Czech Technical University in Prague, Czech Republic
Status of the European Laser Timing ELT Detector package
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Principal participants and contributors Luigi Cacciapuoti, ESTEC, The Netherlands
ESA coordination
Urs Hugentobler, Tech. Univ. Munich, Germanyspace geodesy
Pierre Lauber, TU Munich, GermanySatellite Laser Station Wettzell
Ivan Prochazka, Czech Tech.University in PragueInstrument Science coordinator
Wolfgang Schaefer, TimeTech, Germanytiming devices
Ulrich Schreiber, Tech.Univ.Munich & BKG GermanyData Analysis Coordinator
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
ACTIVITIES in SPACE RELATED PROJECTS Czech Technical University in Prague
new ESA member since 2008
Satellite Laser Ranging since 1972
Picosecond Detector Technology since 1984
Planetary altimetry & LIDAR since 1989
Picosecond Event Timing since 1996
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Satellite Laser Ranging Since 1972, world 3rd country
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Satellite Laser Ranging operation principle
pulsed optical radar
range precision1 .. 3 / mm / shot
operational range0 - 30 ooo km
25 installations onon 5 continents
Graz, Austria
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Single Photon Detectors made by CTU
Si ,200 um,TE3 cooled, vacuum GaAs messa GaAsP, 350 um
Detector for LTT China Complete detector packages
130 mm
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Detectors for Space Applications
CTU Prague & IKI Moscow
MARS 92 (USSR / Russia, 1992-96) Photon counting laser rangefinderMars baloon altimetry
NASA Mars Polar Lander, (USA, 1998) Photon counting LIDAR,Mars surface atmospheric studies
S.P.Pershin et all, IKI Russia
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Laser Time Transfer in Space
LTT – China since April 2007China Compass-M1 / Beidou
T2L2 CNES - France since June 2008 JASON-2
Time and frequency transferusing ps laser pulses in space
Relying on available technologyand ground segment Satellite Laser Ranging
Superb precision and accuracy
Navigation, deep-space, fundamental physics…
E.Samain
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
“H maser in space”, ’94, France + Russia + Praguecanceled
LTT China + PragueCompass M1 Beidou, (operational since Aug. 2007)
T2L2 E. Samain et alACES -> Miriade -> Jason 2 (operational sine June 2008)
ELT proposed by CTU Prague and TU Munich, June 2008I.Prochazka, U.Schreiber
Investigators Working Group established Dec. 2008
Ground tests (Prague, Munich) started Dec. 2008
European Laser Time Transfer ELTHistory review
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
“H maser in space” single photon detection, 100 um SPAD, gated
LTT China single photon detection, 25 um SPAD, not gated + very simple design and construction - modest precision and accuracy ~30 ps - synchronous operation needed /solved/
T2L2 multiphoton, time walk corrected, asynchronous + extremely high precision, asynchronous operation - very high complexity, systematic errors issue
ELT single photon det.,100 um SPAD, gated, temp. comp. + high precision AND accuracy, simple, compact
+/- synchronous operation needed /solved/
Laser Time Transfer - Concepts
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
ELT space optical part conceptLaser retro array, GFZ concept
existing, approved
Detector input aperture
Photon detection chip
Detector optics
NO optical components alignment Very simple and rugged
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Specific accomodation requirements # 1 Field of view of the optical assembly (retro + receiver)
+ / - 60 degrees from nadir un-obscured view
Detector temperature range - IDEAL case any temperature -50..+30 C, stable +/- 2 C- the WORST case range -50…+50 C
Cooling of optical receiver- total heat generated 0.15 W to 5 W depends on configuration- amount of heat depends on detector temperature range (the excess heat is used to temp.stabilize the receiver, if needed)
= > KEY PROBLEM AREA – THERMAL CHANGES of ELT assempbly
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Wettzell ground demonstration experimentDecember 2008 – May 2009
Ground demonstration of the entire timing performance via a space target and SLR combined
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Wettzell ground demonstration experimentDecember 2008 – May 2009
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Wettzell ground demonstration experiment
The experiment feasibility was demonstrated in a completeground experiment
The final precision was impaired by in-appropriate WLRS laser pulse length problem. ( about 230ps instead of 80 ps).
The indoor tests indicate, that for shorted laser pulses the desiredprecision might be reached.
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Precision and accuracy goalsELT detector assembly
Single photon signals only = > no biasesassured by useful data rate ( < 20%)
Detection delay jitter < 30 ps rmsresulting in 3 ps / 100 s
Detection delay stability +/- 3 ps
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Prague group activities - detector
Detector package for WLRS # 1 (delivered) # 2 (reference)
Development of the ELT package Version 1.0 CMOS, very low power OK 1.1 Bias voltage / temperature compensation OK 1.2. Temperature drift compensation in progress
Detection absolute delay determination promissing
Contribution to WLRS experiment
Long term stability tests / SLR Graz / OK
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Development of the ELT packageVersion 1.0 CMOS, low power
CMOS version, low power < 50 mW (detector) < 500 mW (power s.)
Ver. 1.1. Bias voltage / temperature compensation OKdetector bias controlled within the temp. range of -50… +50 C
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Development of the ELT packageVersion 1.1. CMOS, low power
Detection delay dependence~ 60 ps / V at 2.5 V ab
= > +/- 3 ps delay stability using bias stabilizing circuit
Timing jitter < 30 ps overallfor > 1.5 V above48 ps laser pulse
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Detection absolute delay determination
Analysis of the individual contributors Photon - > electron conversion ? << 1 ps Semiconductor propagation ? 1 ps Avalanche build up OK Electronic Detection mechanism OK
Avalanche build up 1.125 ns +/- ?? Electronic detection mech. 8 ps / 1 mV threshold det. Electronics propagation 5.300 ns +/- 7 ps
Independent comparison checks required
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Detector package operation in extreme background regime
Operational up to 200 Mc /s of background photon flux(up to 50 Mc/s are expected)
Gated 100 ns beforesimulation of ELT daylight operation
Timing jitter < 25 ps rms overall using 48 ps laser pulse
Detection delay stability +/- 4psover entire background dynamical range
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Timing stability of the photon counting chainGraz SLR station, SPAD detector
Graz Routine Calibrations 2009/050 - 2009/112Drift due to Stop Pulse / Coax Cable / Temp Coeff
129210129215129220129225129230129235129240129245129250129255129260
-5 0 5 10 15 20 25
Air Temperature [°C]
CA
L Va
lue
[ps]
Series1
NOTE system STABILITY ~ 2.5 ps r.m.s. Cable temp.drift ~ 1 ps / K
= > The /cables/ temperature issue is critical for timing stabilityCables ~ meters are expected to be locate outside .
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
Development of the ELT packageVersion 1.2. CMOS, temperature drift compensation
The new detector electronics is automatically compensating the temperature variations of the detector electronic circuit delayincluding the delay temperature drift of the (long) signal cables
The operation requires Gate ON pulses synchronously with the local time scale
I.Prochazka, ACES IWG Observatoire de Paris, Paris, July 9, 2009
WLRS experiment The experiment indicated the feasibility of the ELT The resulting precision/accuracy goal was has not been met yet due to
unexpected problems with Wettzell hardware (laser pulse) The experiment continues
The development of the ELT detector package in Prague Version 1.0 CMOS, low power OK 1.1 Bias voltage / temperature compensation OK 1.2. Temperature drift compensation in progress Long term detector stability tests / SLR Graz / OK
Actual status of SPAD detector development for ELT-ACES CONCLUSION
top related