Subject: [IGSMAIL-1826] International GLONASS Experiment, IGEX-98 Call for Participation
From: Ruth Neilan for: Pascal Willis, Gerhard Beutler, Werner Gurtner,
Date: Mon, 9 Mar 1998 14:07:37 PST

******************************************************************************
IGS Electronic Mail      Mon Mar  9 14:07:37 PST 1998      Message Number 1826
******************************************************************************

Author: Ruth Neilan for: Pascal Willis, Gerhard Beutler, Werner Gurtner,
Subject: International GLONASS Experiment, IGEX-98 Call for Participation

Guenther Hein, Ruth Neilan, Jim Slater
Subject: International Call for Participation (GLONASS IGEX-98 campaign)

Dear colleagues,

The document below outlines a Call for Participation in an international
campaign for GLONASS observation during the period of September 20 through
December 20, 1998.

All groups are welcome and encouraged to respond positively. People and
institutions already participating in the IGS are strongly encouraged to
answer this proposal if possible.

Any further questions can be directed to Pascal WIllis,
<[email-masked]>, who is leading this effort on behalf of the CSTG.

With best regards, and wishes for successful realization of IGEX-98,

Ruth Neilan
IGS Central Bureau

========================================================================

	      FINAL VERSION (March 6, 1998)

        The International GLONASS Experiment
                      IGEX-98
                Sept 20 - Dec 20, 1998

		document prepared by
      Pascal Willis, Gerhard Beutler, Werner Gurtner
	  Guenter Hein, Ruth Neilan, Jim Slater

 ------------------------------------------------------------

1.  IGEX-98: Description of the Experiment
    --------------------------------------

1.1 Sponsoring Organizations
1.2 The GPS, the GLONASS, and IGS Involvement

2.  Call for Participation
    ----------------------

2.1 IGEX-98 Coordinating Center
2.2 Observing stations
2.3 Data Centers
2.4 Data Analysis
2.5 Evaluation
2.6 Instructions to Answer the Proposal

1. General Description of IGEX-98
   ------------------------------

1.1 Sponsoring International Associations
    -------------------------------------

The International GLONASS EXperiment (IGEX) is an international
campaign sponsored by:

 - the International Association of Geodesy (IAG) Commission VIII,
   International Coordination of Space Techniques for Geodesy and
   Geodynamics (CSTG),

 - the International GPS Service for Geodynamics (IGS),

 - The Institute of Navigation (ION), and

 - The International Earth Rotation Service (IERS).

CSTG is a commission of IAG (International Association of Geodesy)
and  a subcommission of COSPAR (COmmission for SPAce Research) and IGS
is an approved service of IAG and a FAGS-Service (Federation of
Astronomical and Geophysical Data
Analysis Services)

The CSTG Subcommission on "Satellite Microwave Systems" (Chair, Pascal
Willis) is coordinating the project, as it was proposed at the 7th IGS
Governing Board Meeting in September 1997 in Rio de Janeiro (see IGS-Mail
Message 1683).

The ION is a non-profit professional society dedicated to the art and
science of navigation including air, space, marine, land navigation and
position determination.  ION organized a GLONASS-GPS Interoperability
Working Group in 1996 to facilitate solutions to problems related to
coordinate and time reference frames, precise ephemerides, and hardware and
software implementations.

The IERS is a Service of IUGG (International Union of Geodesy and Geophysics)
and IAU (International Astronomical Union) and an approved service of FAGS.

All GLONASS satellites are equipped with arrays of LASER reflectors
allowing the SLR community to range easily to the GLONASS satellites. It
is thus natural to closely coordinate the IGEX-98 with the SLR
Subcommission of CSTG. Werner Gurtner from the IGEX-98 steering committee
is at present considered as "liaison officer" of the IGEX-98 with the SLR
Subcommission of CSTG

1.2 The GPS, the GLONASS, and IGS Involvement
    -----------------------------------------

There are many common aspects of the IGEX-98 and the 1992 IGS Test
Campaign:

 - The GLONASS and the GPS are close relatives from the technical point of
   view (dual-frequency microwave systems in the L-band).

 - At present GLONASS is not fully operational (nor was the GPS in 1992,
although it was more fully developed).

 - Only the broadcast GPS orbits and precise ephemerides from the U.S.
Department of Defense were available in 1992, while only broadcast GLONASS
orbits are currently available.

 - GPS orbits were referenced to WGS 84 in 1992 but not to the ITRF;
GLONASS orbits are referenced to neither WGS 84 nor the ITRF.

For the IGEX campaign, the IGS infrastructure can be exploited to the
extent possible.  In particular, the IGS global network of tracking
stations, its experience with data acquisition and orbit production, and
its ties to the ITRF can be used to support the IGEX.  With this in
mind,the Terms of Reference and the Call for Participation for the
following experiment were presented to and approved by the IGS
Governing Board on February 11, 1998.

1.2 Objectives
    ----------

The main purpose of IGEX-98 is to conduct the first Global GLONASS
Observation Campaign for geodetic and geodynamics applications and to
evaluate the results in an international workshop in 1999. The campaign
duration of three months is intended to simulate an operational
environment, i.e., observations, data transfer, and data analysis have to
be performed in a service-like manner (as opposed to a campaign-oriented
strategy).

The main objectives of IGEX-98 are:

 - set up a global GLONASS observation network,

 - test GLONASS data processing software,

 - determine GLONASS orbits of meter-quality or better in a well-defined
   Earth-fixed reference frame (namely, the ITRF),

 - gain insight into GLONASS orbit modeling peculiarities
   (solar radiation pressure, attitude, etc.),

 - study common GPS/GLONASS processing strategies,

 - engage the collaboration of the SLR community to evaluate the
   accuracy of the determined GLONASS orbits,

 - determine transformation parameters between the GLONASS operational
reference frame and ITRF and WGS 84 (the GPS operational reference frame),

 - connect the GPS and GLONASS time systems,

 - compare receiver equipment performance,

 - compare and contrast the separate and combined satellite systems on a
global basis, and

 - foster participation and cooperation with Russian agencies and
organizations.

1.3 IGEX-98 Schedule
    ----------------

 February 1998  Distribution of IGEX-98 Call for Participation

 May 29, 1998  Proposals due

 June 1998     Evaluation of proposal by Steering Committee
               Review/approval of the schedule

               Designation of the Oversight Commitee (including Chair)

               Campaign Planning Meeting

 September 20, 1998 Campaign begins

 December 20,  1998 Campaign ends

 early 1999    IGEX-98 Evaluation Workshop

1.4 IGEX-98: Organizational Aspects
    -------------------------------

The CSTG Subcommission on Microwave systems is coordinating IGEX-98 with
Pascal Willis as coordinator.

The Steering Committee of IGEX-98 consists of Pascal Willis(IGN) (chair),
Gerhard Beutler (AIUB), Werner Gurtner (AIUB), Ruth Neilan (JPL),
Guenther Hein (UbM), Jim Slater (NIMA).
The Steering Committee prepares and sends out the Call for Participation,
evaluates and answers the proposals received.

After this evaluation, IGEX-98 will be coordinated by a
broad-based International
Organizing Committee consisting of participants in IGEX-98. The steering
committee will be dissolved.

Participation in the IGEX-98 is requested for the following activities:

 - Observing station(s)
 - Data Center(s)
 - Analysis Center(s)
 - Evaluation of Results

Additional information may be found below and in the following Web sites:
http://lareg.ensg.ign.fr/IGEX
http://www.ion.org/workgroup.html

2. CALL FOR PARTICIPATION
   ----------------------

The Steering Committee of the IGEX-98 is seeking participants for the 1998
International GLONASS Experiment. The description of the campaign is
contained in Section 1 of this document.

In particular, we are seeking

 - IGEX-98 Observing Sites
 - IGEX-98 Data Centers
 - IGEX-98 Data Analysis Groups
 - IGEX-98 Evaluation Groups

2.1 Observing Sites
    ---------------

2.1.1 Receivers
      ---------

Only geodetic-type receivers (capable of collecting pseudorange and carrier
phase observations) may be used in IGEX-98.  Receivers must be able to
track at least four GLONASS satellites simultaneously and, if combined with
a GPS receiver, at least four GPS satellites simultaneously.

In particular, and in sequence of preference, the following receiver types
may be used in IGEX-98:

 - Combined dual-frequency GPS/GLONASS receivers
 - Dual-frequency GLONASS receivers
 - Combined single-frequency (L1) GPS/GLONASS receivers
 - Single-frequency GLONASS receivers

Receivers must be colocated with or tied to sites that have well-determined
ITRF coordinates.  IGS sites are preferable.  The ITRF coordinates should
have an accuracy of 1-5 cm.  In cases where there are no suitable ITRF
coordinates available at a site, a dual-frequency geodetic-quality GPS
receiver must be colocated with the GLONASS receiver to collect sufficient
GPS data during the experiment to compute ITRF coordinates for the site at
the specified accuracy.  This may be done by relative positioning to a
nearby IGS site or by absolute positioning.

In the case of single-frequency GLONASS receivers, it is absolutely
mandatory that a dual-frequency geodetic-quality GPS receiver is operating
during the whole campaign on the same site on a marker with known or
determinable ITRF coordinates (within a distance of less than a few hundred
meters from the GLONASS receiver). The local ties between the two antennae
should be available with an accuracy of less than 1 cm (in ITRF).

A GLONASS Site Information Report must be available at the IGEX-98
Coordination Center prior to the observation campaign (format identical to
IGS site documentation form, available at the IGS Central Bureau
Information System, see ftp://igscb.jpl.nasa.gov/igscb/resource/blank.log).

If the IGEX-98 receiver is driven by an accurate external clock (rubidium,
cesium or hydrogen standard), this information should be included in the
proposal.

2.1.2 Operational considerations
      --------------------------

The IGEX-98 will be based on a 30s sampling rate.

The data must be forwarded to an IGEX data center within 48 hours from the
end of the UT day on which it was collected.

The exchange file format is the RINEX format (see ftp://igscb.jpl.nasa.gov/
igscb/data/format/rinex2.txt).

The following naming conventions will be followed:

A 4-character acronym for each receiver operated during the campaign should
be proposed to and approved by the IGS Central Bureau
([email-masked]).

For each marker, a DOMES number (a globally unambiguous marker number used
by ITRF) has to be requested from the ITRF Section of the IERS Central
Bureau (see http://lareg.ensg.ign.fr/ITRF/domesreq.html, e-mail contact:
[email-masked]).

The proposal should specify what quality control will be performed before
sending the data to a data center.

Detailed guidelines for the data handling will be provided together with
the approval of the proposal.

2.1.3 Local Geodetic Ties
      ----------

The local geodetic ties between the GLONASS equipment and all geodetic
equipment in the vicinity (GPS, DORIS, SLR, VLBI, PRARE,..) must be
performed, documented and made available before the start of IGEX-98.
They have to be reported as Cartesian coordinate differences (delta X/Y/Z)
parallel enough to the earth-centered ITRS to maintain the accuracy of a
few millimeters.

2.2 Data Centers
    ------------

The proposal should describe the maximum number of stations from which data
can be received, stored and made available for anonymous ftp access.

Data upload from the stations to the data center should be performed
through ftp (anonymous or by user account/password), too. However, it will
be the responsibility of the data centers to coordinate the data upload
with the observing sites.

The data should be available online within hours after reception from the
observing organizations and for at least 3 months after the campaign.
Offline availability upon request should be maintained for at least 2
years.

Data centers should fill out a data center description form available at
ftp://igscb.jpl.nasa.gov/igscb/center/data/BLNKFORM.DCN.

2.3 Data Analysis
    -------------

Data Analysis Groups will process the GLONASS IGEX-98 data. It is expected
that after some time they may be able to produce results
on a daily or a weekly basis. They should make them available
for comparisons (or combinations) as early as possible.

IGEX-98 Data Analysis Groups should briefly describe planned analysis. It
is expected, however, that GLONASS ephemerides and GLONASS satellite clock
information will be the main result. In the response to the Call for
Participation, the Analysis Groups should indicate which of the following
items they plan to produce:

 - precise GLONASS ephemerides (in SP3-Format, see
   ftp://igscb.jpl.nasa.gov/data/format/sp3.txt) and/or
 - GLONASS satellite clocks  and/or
 - Earth rotation parameters  and/or
 - stations coordinates (in SINEX files, see
  ftp://igscb.jpl.nasa.gov/igscb/datga/format/sinex.txt)  and/or
 - other information (e.g., ionosphere, troposphere, etc.)

2.4 Data Evaluation
    ------------------

In IGEX-98 we envisage that two kinds of orbit/clock evaluations
will be done

(1) Comparison of results (obtained by the various Analysis Groups)
similar to those routinely performed by the IGS Analysis Coordinator

(2) Evaluation based on independent techniques, i.e., SLR observations.

We are seeking participation in both domains. In case (1) we would prefer a
proposal from an IGS- and/or and IGEX-Analysis Group, in case (2) a
proposal from an SLR Analysis Center.

2.5 Instructions for Submitting a Proposal
    -----------------------------------

Proposals submitted in response to the Call for Participation should
contain:

 - a cover letter signed by an official representative of the organization
 - the attached cover sheet
 - a detailed plan describing the activities proposed by the organization

It should be clear in the proposal which organizations are cooperating or
assumed to contribute and whether the organization(s) would consider
continuing their activities after the end of the observation campaign (Dec
20, 1998).

Send proposals to:

 Pascal Willis
 Institut Geographique National
 ENSG/LAREG                            Phone: 33-(0)1-6415-3254
 6-8 Avenue Blaise Pascal              FAX:   33-(0)1-6415-3253
 Cite Descartes, Champs-sur-Marne      e-mail: [email-masked]
 77455 Marne-la-Vallee, France

 ---------------------------------------------------------
Proposal Submitted in response to the
Call for Participation
International GLONASS Experiment (IGEX-98)

Proposing Organization:

Point of Contact:
  Name
  Address
  Telephone
  FAX
  email

Authorizing Official
  Name
  Address
  Telephone
  FAX
  email

  signature

Proposal for
    Stations Observations
    Data Management
    Data Analysis
    Evaluation

For Joint proposals:

  Collaborating institutions

  Contacts

Detailed proposal (see attached requirements)

 -------------------------------------------------------

============================================================================
Ruth E. Neilan                    Telephone:   (818)-354-8330
IGS Central Bureau                FAX:         (818)-393-6686
Jet Propulsion Laboratory         E-mail (IGS):     [email-masked]
MS 238-540                        E-mail (personal): [email-masked]
4800 Oak Grove Drive              E-mail (UNAVCO):  [email-masked]

Pasadena, CA 91109

World Wide Web:  http://igscb.jpl.nasa.gov/
============================================================================

[Mailed From: "Ruth E. Neilan" <[email-masked]>]