Site Log Procedure

ILRS Site and System Information Form Instructions

Author: Werner Gurtner; Networks and Engineering Working Group
Editor: Van Husson, Mike Pearlman; Central Bureau

A. INTRODUCTION

The form is primarily intended to be used as a description of a fixed SLR system at a given site.

By selectively filling out parts of the form only, it can be used to describe a (mobile) system or a site to be visited by a mobile laser system.

The form is meant to be supplemented whenever system parameters or other information maintained by the form have changed. Thus the form will also serve as a historical collection of major changes during the lifetime of an SLR system and/or its site.

B. INPUT FIELDS and FORMAT

The form is a simple ASCII file with a limit of 80 characters per line. Entries into the form are made following the colon after the explanation of the entry. The responses can be in either upper or lower case or can be used in combination.

In the rest of this document to distinguish prompts from sample answers, prompts in the site log will be preceded by a > and completed answers (including the prompt) will be preceded by a !, but please do not use these prompts (>,!) in your completed site logs.

>	City or Town	:

Insert one blank after the colon.

!	City or Town	:		Zimmerwald

For some of the fields, predefined keywords are given in the input field:

>	Transmit/Receive Switch	:		(PERFORATED MIRROR/NONE/POLARIZER/etc)

For example, keep just the appropriate keyword in the field or enter a new one

!	Transmit/Receive Switch	:		PERFORATED MIRROR
!	Transmit/Receive Switch	:		Rotating Mirror

Fields for values of given format or length:

>	Date Prepared	:		(yyyy-mm-dd)
>	IERS DOMES Number	:		(xxxxxxxxx)

Insert proper value

!	Date Prepared	:		2000-02-04
!	IERS DOMES Number	:		14001S007

Some fields can expand over several lines:

>	Additional Information	:		(multiple lines)

Keep line length to 80 characters, use indentation on subsequent lines

!	Additional Information	:		Internal target, the range to which is not directly observable with geodetic mean

Fields with unknown information:

>	Date Removed	:		(yyyy-mm-dd hh:mm UT)

Leave it as it is:

!	Date Removed	:		(yyyy-mm-dd hh:mm UT)

Fields not applicable to the current system:

>	Mark Description	:		(CHISELLED CROSS/DIVOT/BRASS NAIL/N.A./etc

e.g., for a mobile system: Select N.A.

!	Mark Description	:		N.A.

C. HISTORY / MODIFICATIONS

Most of the sections or subsections contain information that may change with time. Therefore they contain the start and end date, date of installation and removal or first and last applicable date.

Each section or subsection is numbered according to the modifications in time:

Original Form:

>9.02.xx	GPS Timing Rcvr Model	:
>	Manufacturer	:
>	Date Installed	:		(yyyy-mm-dd hh:mm UT)
>	Date Removed	:		(yyyy-mm-dd hh:mm UT)

First entry:

!9.02.01	GPS Timing Rcvr Model	:		XL-DC
!	Manufacturer	:		TrueTime
!	Date Installed	:		1995-08-16
!	Date Removed	:		(yyyy-mm-dd hh:mm UT)

Modification: Add date of removal, insert new block:

!9.02.01	GPS Timing Rcvr Model	:		XL-DC
!	Manufacturer	:		TrueTime
!	Date Installed	:		1995-08-16
!	Date Removed	:		(yyyy-mm-dd hh:mm UT)

!9.02.01	GPS Timing Rcvr Model	:		YL-DC
!	Manufacturer	:		TrueDate
!	Date Installed	:		1999-12-20 11:00
!	Date Removed	:		(yyyy-mm-dd hh:mm UT)

D. COMMENTS ON INDIVIDUAL ENTRIES

>1.	Identification of the Ranging System Reference Point (SRP)

In most cases, the SRP is the intersection point of the azimuth and elevation axes.

>3.	General System Information
>	4-Character Code	:		(xxxx)

Take the code from the Table in APPENDIX 1 below.

>4.	Telescope Information
>	Max Slew Rate Az        [deg/s]	:
>	Max Slew Rate El         [deg/s]	:
>	Max Used Tracking Rate Az	:
>	Max Slew Rate El	:

Some systems have a high slew rate for rapid positioning, but cannot be used for tracking. Enter the maximum rate that can be used for tracking.

>5.	Laser System Information

As generated by the laser, e.g.,

>1.	Identification of the Ranging System Reference Point (SRP)

In most cases, the SRP is the intersection point of the azimuth and elevation axes.

>3.	General System Information
>	4-Character Code	:		(xxxx)

Take the code from the Table in APPENDIX 1 below.

!	Primary Wavelength        [nm]	:		1064
!	Primary Maximum Energy[mJ]	:		100
!	Secondary Wavelength    [nm]	:		532
!	Secondary Max. Energy    [mJ]	:		40

- Note: Primary Maximum Energy before frequency doubling

>6.	Receiver System

!6.01.01	Primary Chain
!	Wavelength                      [nm]	:		532
!6.02.01	Primary Chain
!	Wavelength                      [nm]	:		1064

"Primary" is the one primarily used for ranging, so its wavelength in the example above is 532 nm.

The "Secondary" chain wavelength in the example above is 1064 nm.

>	Detector Type
>	Field of View                      ["]	:		(minimum-maximum or fixed value)

Field of view (diameter) for the detector. Minimum and maximum value if variable, one value only if fixed.

>7.	Tracking Capabilities
>	Very Low Alt (<400 km)	:		(YES/NIGHT/NO)

YES means day and night, NIGHT is night time only and NO means beyond system capability.

>8.	Calibration
>	Edit Criterion 1st Chain	:		(ITERATIVE n.n SIGMA/MANUAL/NONE/etc)

Example: ITERATIVE 2.5 SIGMA indicates a 2.5-sigma rejection level

>9.	Time and Frequency Standards
>	Short Term Stab. [e-12]	:		(ITERATIVE n.n SIGMA/MANUAL/NONE/etc)
>	Long Term Stab. [e-12]	:		(ITERATIVE n.n SIGMA/MANUAL/NONE/etc)

What is the short and long term stability of your frequency source at 1 second and 1 day, respectively, in parts to 10 to the minus 12?

>12.	Meteorological Instrumentation
>	Height Diff to SRP              [m]	:

Plus sign if barometer is above the system reference point, minus sign if barometer is below.

If reported barometer readings are corrected to the height of the laser reference point, indicate zero as height difference!

E. RETRIEVING THE BLANK LOG

Get the blank log via anonymous ftp from the CDDIS

                Node Name:  cddis.gsfc.nasa.gov
                IP:         128.183.102.102
                Directory:  pub/reports/slrlog
                File name:  slr_blank.txt
                URL:        ftp://cddis.gsfc.nasa.gov/reports/slrlog/slr_blank.txt
            

F. SUBMISSION OF THE LOG

Send the completed log to the Central Bureau at cb@cddis.gsfc.nasa.gov.

Whenever the form has been supplemented with new information, follow this same procedure.

The Central Bureau and the Networks and Engineering WG will review each log for proper format and data integrity. Any format or data integrity issues will be coordinated by the Central Bureau with the appropriate site log author.

G. FILE NAMING CONVENTION

The Central Bureau will name each site log following the file naming convention below:

                SSSS_YYYYMMDD.log
                with:
                    SSSS = 4-character code of the station
                    YYYY = year of submission
                    MM	 = month of submission
                    DD	 = day of submission
            

Example: The Zimmerwald site log that was produced on 18 August 2000 will be named:

ziml_00000818.log

H. AVAILABILITY OF THE LOGS

The logs of all stations are available from the CDDIS.

                Node Name:  cddis.gsfc.nasa.gov
                IP:         128.183.102.102
                Directory:  pub/reports/slrlog/
                URL:        ftp://cddis.gsfc.nasa.gov/reports/slrlog
            

Old logs will be available and moved to a separate directory:

ftp://cddis.gsfc.nasa.gov/reports/slrlog/oldlog/

I. UPDATING THE LOGS

To update your log please get the latest version of your log from the CDDIS (see previous section), update the appropriate sections by following the procedure in Section C and then submit your updated log following the procedure in Section F.

APPENDIX 1

4-Character Code for Laser Stations

Note: Whenever possible, the IGS/GPS code was taken by replacing 4th character by L for Laser (M for Grasse Lunar Station, M for Matera MLRO, T for TIGO, TROS, TLRS, and F for FTLRS).

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Last modified date: Monday, 30-Jan-2006 10:32:50 EST
Author: Carey Noll
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