Potsdam
SLR System Configuration Definition
SYSTEM CONFIGURATION DEFINITION
===============================
SYSTEM NAME: GFZLAS (Potsdam)
PAD ID NO.: 78365801
ADDRESS: Telegrafenberg A 17, D-14473 Potsdam, Germany
CONTACT: Dr. R. Neubert, Dr. L. Grunwaldt
PHONE: (+49)-(0331)-288-1153, -1156
FAX: (+49)-(0331)-288-1111
E-MAIL: lasgrp@gfz-potsdam.de
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SECTION 1.0 - SYSTEM RANGING CAPABILITY
=======================================
SECTION 1.1 SYSTEM RANGING FEATURES
===================================
FEATURES /CURRENT RANGING / RANGING / DATE / FUTURE /
/CAPABILITY / PHOTOELECTRON / / RANGING /
/ CAPABILITY/
===============================================================================
Calibration:
Internal / test only / 0.1 - 10 /05-16-94/ *see below* /
External / yes / 0.1 - 10 /05-16-94/ /
* Internal calibration is used at the moment only to calibrate the short
external path; regular implementation foreseen still in 1994 *
SECTION 1.2 ADVANCED SYSTEM RANGING FEATURES
============================================
TARGET /CURRENT RANGING / RANGING / DATE / FUTURE /
/CAPABILITY / PHOTOELECTRON / / RANGING /
/ CAPABILITY/
===============================================================================
Two-Color Capability/ no / /05-16-94/ test only /
Manual Track / no / /05-16-94/ N/A /
Tracking:
Semi-Automated / yes (*) / 0.1 - 5 /05-16-94/ /
Fully Automated / no / /05-16-04/ N/A /
* Computer controlled tracking starts from a manually set start
position *
Section 1.3 System Ranging Targets
===================================
TARGET /CURRENT RANGING / RANGING / DATE / FUTURE /
/CAPABILITY / PHOTOELECTON / / RANGING /
/ CAPABILITY/
==============================================================================
STARLETTE / day/night / 0.3 - 5 /07-01-94/
STELLA / day/night / 0.3 - 5 /07-01-94/
ERS-1 / day/night / 0.3 - 5 /07-01-94/
AJISAI / day/night / 0.3 - 5 /07-01-94/
TOPEX / day/night / 0.3 - 10 /07-01-94/
LAGEOS 1 / day/night / 0.1 - 0.5 /07-01-94/
LAGEOS 2 / day/night / 0.1 - 0.5 /07-01-94/
ETALON 1 / night / 0.1 - 0.2 /05-16-94/
ETALON 2 / night / 0.1 - 0.2 /05-16-94/
GLONASS 3 / night / ? (not tested) /05-16-94/
GPS-3,5 / night / 0.02 /05-16-94/
Geosynchronous / / / /
Satellite / night / ? (not tested) /05-16-94/
Moon / no / /05-16-94/ N/A
SECTION 2.0 - HARDWARE CONFIGURATION / CAPABILITY
=================================================
SECTION 2.1 LASER CONFIGURATION CATEGORY
========================================
LASER / SPECIFICATIONS / DATE / FUTURE / APPROX./
/ / / CHANGES / DATE /
================================================================================
Type of Laser Medium / Nd:YAG / 05-16-94 / N/A / /
Energy / Pulse (mJ) / 10 mJ/ 05-16-94 / 20 - 40 /03-01-95/
Pulsewidth (ps) / 35 ps/ 07-01-94 / 35 / /
Beam Size / 1 m / 05-16-94 / N/A / /
Beam Divergence(Half Angle) 50 - 500 microrad/ 05-16-94 / N/A / /
Beam Divergence Control / manual / 05-16-94 / N/A / /
Amplitude Stability / 10 %/ 07-01-94 / / /
Timing Stability / 10000 ns/ 05-16-94 / N/A / /
Transverse Mode Structure / cm/ / / /
Ranging Wavelength(s) / 532 nm/ 05-16-94 / / /
Repetition Rate / 10 Hz/ 05-16-94 / N/A / /
Other / act.- pass. mode-/ 07-01-94 / / /
locking
SECTION 2.2 MOUNT CONFIGURATION CATAGORY
========================================
SECTION 2.2.1
=============
TELESCOPE/ MOUNT / SPECIFICATIONS / DATE / FUTURE / APPROX./
/ / / CHANGES / DATE /
================================================================================
Telescope Type /Cassegrain-Mangin / 05-16-94 / N/A / /
Biaxial Telescope / / / / /
Monoaxial Telescope / yes / 05-16-94 / N/A / /
Mount Type / az - alt / 05-16-94 / N/A / /
Field of View / 10' (TV guide) / 05-16-94 / N/A / /
Focal Length / 11.6 m / 05-16-94 / N/A / /
Magnification / 100 / 05-16-94 / N/A / /
Pointing Accuracy / 20 arcsec / 05-16-94 / / /
After STARCAL
Satellite:
Common T/R Optical Path / yes / 05-16-94 / N/A / /
Separate T/R Optical Path / no / / / /
Calibration:
Common T/R Optical Path / no / 05-16-94 / yes /08-01-94/
Separate T/R Optical Path / yes / 05-16-94 / / /
Orthogonality of Axes / / / / /
Wobble on Each Axis:
Elevation / 10 arcsec / 05-16-94 / / /
Azimuth / 10 arcsec / 05-16-94 / / /
Elevation
- Range / 0 - 90 deg / 05-16-94 / / /
- Encoder Resolution / 1e-4 deg / 05-16-94 / / /
- Position Jitter / 15 arcsec / 05-16-94 / / /
- Maximum EL Velocity / 1.5 deg/sec / 05-16-94 / / /
- Maximum EL Acceleration/ 1 deg/sec/sec / 05-16-94 / / /
Azimuth
- Range / -180 - +180 deg / 05-16-94 / / /
- Encoder Resolution / 1e-4 deg / 05-16-94 / / /
- Position Jitter / 15 arcsec / 05-16-94 / / /
- Maximum Az Velocity / 1.5 deg/sec / 05-16-94 / / /
- Maximum Az Acceleration/ 1 deg/sec/sec/ 05-16-94 / / /
PRIMARY MIRROR
Type / spherical / 05-16-94 / / /
Clear Aperture (CA) / 1 m / 05-16-94 / / /
Focal Length / 1.2 m / 05-16-94 / / /
Optical Coating / Aluminium / 05-16-94 / / /
SECONDARY MIRROR / / / / /
Type / * see below* / 05-16-94 / / /
Clear Aperture (CA) / 0.25 m / 05-16-94 / / /
Focal Length / / / / /
Optical Coating / none / 05-16-94 / / /
* secondary mirror is a negative lens with Al- coating from backside *
TERTIARY MIRROR / none / / / /
Type / / / / /
Clear Aperture / / / / /
COUDE MIRRORS / / / / /
Type / flat / 05-16-94 / / /
Clear Aperture / 20 cm / 05-16-94 / / /
Optical Coating / Aluminium / 05-16-94 / / /
SECTION 2.3 OPTICAL CONFIGURATION CATAGORY
==========================================
TRANSMIT/ RECEIVE OPTICS / SPECIFICATIONS / DATE / FUTURE / APPROX./
/ / / CHANGES / DATE /
================================================================================
T/R Coupling Scheme:
- Type / rotating mirrors / 05-16-94 / / /
- Coupling Efficiency / 99 per cent / 05-16-94 / / /
Spatial Filter: / / / / /
- Field of View / 1 arcmin / 05-16-94 / / /
Band-Pass Filter: / / / / /
- Type / dielectric / 05-16-94 / / /
- Bandwidth / 2 nm / 05-16-94 / 0.15 nm /08-01-94/
- Blocking Bandwidth / UV - IR / 05-16-94 / / /
- Transmission Efficiency/ 60 per cent / 05-16-94 / 40 per cent/08-01-94/
Receive Signal Amplitude
Control Mechanism / yes / / / /
SECTION 2.4 TRANSMIT/ RECEIVE (T/R) ELECTRONICS CONFIGURATION SECTION
=====================================================================
T/R ELECTRONICS / SPECIFICATIONS / DATE / FUTURE / APPROX./
/ / / CHANGES / DATE /
================================================================================
Transmit Detector: pin-silicon photodiode /
- Quantum Efficiency / 0.05 @ 1064 nm / 05-16-94 / / /
- Gain / / / / /
- Bandwidth / 1.5 GHz / 05-16-94 / / /
- Jitter (single pe) / 20 ps / / / /
- Impulse Response
- Pulse Width / 2 ns / 05-16-94 / / /
- Rise Time / 600 ps / 05-16-94 / / /
- Dynamic Range / .01 - 3 V / 05-16-94 / / /
Receive Detector #1 / PMT H 5023 / 05-16-94 / / /
- Quantum Efficiency / 0.08 @ 532 nm / 05-16-94 / / /
- Gain / 1e7 / 05-16-94 / / /
- Bandwidth / 1.5 GHz / 05-16-94 / / /
- Jitter (single pe) / 60 ps RMS / 05-16-94 / / /
- Impulse Response
Pulse Width/Rise Time / 1 ns / 0.6 ns / 05-16-94 / / /
- Dynamic Range / 0.1 - 1.2 V (*) / 05-16-94 / / /
* After amplifier, saturation starts at 1.2 Volts
Amplifier
- Type: / C 4267 / 05-16-94 / / /
- Bandwidth: / 1 GHz / 05-16-94 / / /
- Jitter: / / / / /
- Dynamic Range / 0.1 - 1.5 V / 05-16-94 / / /
Receive Detector #2 / APD RCA 30902 / 05-16-94 / SPAD 100um /03-01-95/
- Quantum Efficiency / 0.35 @ 532 nm / 05-16-94 / 0.2 @ 532nm/03-01-95/
- Jitter (single pe) / 130 ps RMS / 05-16-94 / 35 ps RMS /03-01-95/
- Pulse Width/Rise Time / 10 ns / 1.5 ns / 05-16-94 / 10 ns/ 2 ns/03-01-95/
TARGET IMAGING Capability / yes / / / /
- Type of camera / intensified CCD / 05-16-94 / / /
- Gain / / / / /
- Sensitivity / 20 microlux / 05-16-94 / / /
Signal Processing Technique
- Type of Device / Tennelec 454 / 05-16-94 / N/A / /
- CFD:
- Length of External
Delay Cable / 6 cm / 05-16-94 / / /
- Bandwidth / >1.5 GHz / 05-16-94 / / /
- Dynamic Range(pe) / 1 - 8 / 05-16-94 / / /
- Jitter / 20 ps / 05-16-94 / / /
EVENT TIMER or TIME OF FLIGHT MEASUREMENT? Time-of-flight
- Clock Frequency / 5 MHz / 05-16-94 / N/A / /
- Number of Channels / 1 / 05-16-94 / N/A / /
- Number of Verniers / / / / /
- Minimum Dead Time / / / / /
- Time Resolution / 4 ps / 05-16-94 / / /
- Aggregate Jitter / 15 ps / 05-16-94 / / /
Amplitude Measurement / / / / /
- Type of Device / selfmade / 05-16-94 / / /
- Bandwidth / 1.5 GHz / 05-16-94 / / /
- Accuracy / 3 bit / 05-16-94 / / /
- Part of Data Stream? / no / 05-16-94 / yes /10-01-94/
System Delay Calibration / / / / /
Internal Calibration Capability
Location of Target(s) / * see below * / / / /
Range of Target(s) / ** 1.14 m ** / 05-16-94 / / /
External Calibration Capability
Location of Target(s) / + see below + / / / /
Range(s) of Target(s) / 2.7 m / 05-16-94 / / /
* Tripelprism in front of telescope
** Distance from reference plane
+ Located at the inner wall of the station, light path does not include
the main telescope
SECTION 2.6 TIMING CONFIGURATION SECTION
========================================
TIMING / SPECIFICATIONS / DATE / FUTURE / APPROX./
/ / / CHANGES / DATE /
================================================================================
Frequency Standard(s) used/ HP 5061A (Cs) / 05-16-94 / N/A / /
Frequencies / 5 MHz / 05-16-94 / N/A / /
Short-Term Stability / / / / /
Long-Term Stability / 5 e-12 / 05-16-94 / / /
Epoch Time Measurement: / / / / /
- Type of Device / selfmade / 05-16-94 / N/A / /
- Resolution / 100 ns / 05-16-94 / / /
- Timing Closure / 50 ns / 05-16-94 / / /
SECTION 2.7 METEOROLOGICAL SENSORS CONFIGURATION CATAGORY
=========================================================
METEOROLOGICAL SENSORS / SPECIFICATIONS / DATE / FUTURE / APPROX./
/ / / CHANGES / DATE /
================================================================================
Thermometer / * see below * / / / /
Type / / / / /
Accuracy (calibrated) / 0.2 K / 05-16-94 / / /
Resolution / 0.1 K / 05-16-94 / / /
Range / / / / /
Barometric Pressure System/ / / / /
Type / Mercury / 05-16-94 / / /
Accuracy (calibrated) / 0.1 hPa / 05-16-94 / / /
Range / 800 - 1100 hPa / 05-16-94 / / /
Relative Humidity System / * see below * / / / /
Type / / / / /
System Accuracy / 3 per cent / 05-16-94 / / /
Resolution / 0.1 per cent / 05-16-94 / / /
System Range / 20-100 per cent / 05-16-94 / / /
Wind Measurement System / none / / / /
Type / / / / /
Type: / / / / /
Sensor / / / / /
Range / / / / /
Accuracy / / / / /
Resolution / / / / /
Threshold / / / / /
* Sensors for temperature, pressure, humidity integrated into TM 100
meteorological station. For reasons of better calibration, external
mercury barometer is used instead of electronic sensor at the moment.
SECTION 4.0 SURVEY MEASUREMENT CONFIGURATION / CAPABILITY
=========================================================
SECTION 4.1 SURVEY MEASUREMENTS
===============================
SURVEYING INSTRUMENT / ACCURACY / PRECISION
============================================================================
TRIMBLE 4000SSE (GPS) /2-3mm(height),2mm(distance)/
GEODIMETER System 500 /0.02 deg(horizontal angle) /
/0.001deg(vertical angle) /
/0.002m (distance) /
Nd-YAG (Station 7836) * /1.5-2 cm (single shot) / 3-5 mm
* As an additional verification, the distance between station 7836 and a prism
over marker HTS (see 4.4) was measured directly by the laser transmitter/
receiver electronics. The coincidence with the distance derived from GPS/
GEODIMETER was within a few millimeters.
SECTION 4.2 SURVEY ANALYSIS
===========================
SURVEY ANALYSIS TECHNIQUE
================================================================================
* Survey within a local geodetic network. Processing of GPS-data with software
* TRIMVEC-plus (GPS-vectors) and TRIMNET for network adjustment. ITRF92 as
* datum for coordinate transformation (reference: ITRF92 coordinates of SLR-
* station 1181/SBG).
SECTION 4.3 SURVEY CALIBRATION TARGET
=====================================
TARGET / TYPE / RANGE / AZ / EL / RANGE / RANGE / SHORT / LONG
/ / ACCURACY/ / / PRECISION / / TERM / TERM
/ / / / / / / STABILITY / STABILITY
===============================================================================
1 /diffus/ 1mm / 270 / 0 / 1mm /2.671 m/ 1mm / 1mm
2 /prism / 1mm / * / * / 1mm /1.145 m/ 1mm / 1mm
3 / / / / / / / /
4 / / / / / / / /
* prism in front of main telescope
SECTION 4.4 ECCENTRICITY DETERMINATION
======================================
*see below*
/ NORTH / EAST / UP
===============================================================================
Mean Value / -25.535 m / -26.577 m / -13.024 m
Accuracy / 0.003 m / 0.003 m / 0.002 m
Precision / 0.001 m / 0.001 m / 0.001 m
Short Term Stability / 0.001 m / 0.001 m / 0.001 m
Long Term Stability / 0.001 m / 0.001 m / 0.001 m
* Eccentricities given with respect to marker HTS (Helmert tower south).
* Eccentricities of station 1181/SBG with respect to marker HTS are:
* North 1.611 m, East 0.423 m, Height 1.355 m
SECTION 5.0 CALIBRATION TECHNIQUE / CAPABILITY
==============================================
SECTION 5.1 CALIBRATION DEVICES AND FREQUENCY
=============================================
===============================================================================
// FREQUENCY
===============================================================================
DEVICE/ FEATURE / SATELLITE / PASS / DAY / MONTH / YEAR
===============================================================================
Event Timer / / / / /
Time of Flight Devices / / / / / 4 times
Discriminator / / / / X /
Pressure Sensor / / / / / X
Temperature Sensor / / / / / X
Timing System / / / X / /
System Delay / / X / / /
SECTION 6.0 SYSTEM TIMING CLOSURE CONFIGURATION
===============================================
SECTION 6.1 TIMING CLOSURE
===========================
Reference Time: Cs-clock + GPS
Accuracy of Timing: 200 ns with respect to UTC (when no common-view
technique is used)
Modeling of Time Drift: not yet
SECTION 7.0 SYSTEM DATA ANALYSIS CONFIGURATION / CAPABILITY
===========================================================
SECTION 7.1 DATA ANALYSIS
=========================
DATA CORRECTIONS ( YES : NO ) / ADDITIONAL INFORMATION
=============================================================================
7.1.1 Transmit Signal Amplitudes: no /
7.1.2 Receive Signal Amplitudes: no / foreseen still for 1994
in case of use of PMT
only; APD/SPAD is
delivering uniform
receive signal
7.1.3 Timing yes / offset between station
time base and UTC(GPS)
is corrected steps of
100 ns
7.1.4 Instrument Non-Linearities no /
7.1.5 Geometric Corrections no /
7.1.6 Atmosphere no /
SECTION 7.2 System Delay Computation:
======================================
SYSTEM DELAY COMPUTATION FREQUENCY / ( YES : NO ) /ADDITIONAL INFORMATION
===============================================================================
7.2.1 Shot by Shot: / no /
7.2.2 Burst or Short Time Aggregate: / no /
7.2.3 Aggregate: / yes / pre- and postpass
SECTION 7.3 DATA ANALYSIS TECHNIQUES / CAPABILITIES
===================================================
7.3.1 Normal Point Computation: On-site normal points for all
satellites
7.3.2 Fitting Routine (Algorithms): Orbital integrator by Appleby &
Sinclair (RGO); modified version
for use on PC
7.3.3 Noise Filtering and Editing Procedures: 1. O-C based on IRV's
2. polynomial fitting of
residuals (poly order as
low as possible)
3. editing (usually 2.5 sigma)
7.3.4 Data Quality Control Procedures: LAGEOS 1/2: weekly reports from
UoT/CSR (Eanes)
ERS-1/MET.-3: bulletins from
D-PAF others: *see below*
7.3.5 System Computational Capability: PC HP Vectra (80386), to be
replaced in 1995 by80586 type PC
* delivery of DDNA (CDSLR/OAS) for station 7836 was stopped in mid 1993 for
unknown reasons*
SECTION 8.0 SYSTEM ATMOSPHERIC TECHNIQUES
==========================================
SECTION 8.1 ATMOSPHERIC MODEL
=============================
8.1 Atmospheric Model Used: none
* ( PLEASE DESCRIBE THE MODEL IN AS MUCH DETAIL AS POSSIBLE )
SECTION 9.0 SYSTEM PERFORMANCE CHARACTERISTICS
================================================
SECTION 9.1 RANGING SYSTEM ERRORS
=================================
RANGING SYSTEM ERRORS / ACCURACY / 1 SIGMA / PEAK - PEAK / DATE /
================================================================================
Temporal Stability / / 5 mm / 10 mm / /
Wavefront Distortion / / * see below/ / /
Signal Strength Dependence / /** see below/ / /
Calibration Path / / 1 mm / / /
Mount Eccentricities / / 1 mm / / /
Meteorological Measurement / / 1 mm / / /
Event Timer / / / / /
Time of Flight Measurement / /***15 mm / / /
Epoch Time Measurement / / .3 mm / / /
Data Analysis / /negligible / / /
Normal Point Computation / / 1 mm / / /
System Delay Computation / / / / /
Comments:
* not measured; laser is operated in transverse fundamental mode, so no
considerable effect is expected
** dependent on detector used:
1.-using APD RCA 30902 : about -250ps/decade for levels above 1 pe
2.-using SPAD or PMT : about -100ps/decade for levels above 1 pe
Station is generally operated at levels well below 1 pe for all targets
*** Including laser parameters; TOF counter+CFD alone: 5 mm
--
Dr. L. Grunwaldt
GeoForschungsZentrum Potsdam
Telegrafenberg A17
D-14473 Potsdam
Germany
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