ETS-8
ILRS Mission Support Status:
Satellite laser ranging data will be used for precision orbit determination.
One of the missions of the Engineering Test Satellite 8 (ETS-8/ETS-VIII) is a space-based positioning experiment using the navigation signal (S-band and L-band), like GPS, generated by HAC (High Accuracy Clock system) using CFS (Cesium Frequency Standard). The requirement of estimation/synchronization accuracy orbit and clock are 100m and 10nsec, respectively. ETS-8 and GPS satellite orbits and clocks will be estimated on a real-time basis. In order to evaluate the results of this real-time orbit determination, the high accuracy orbit will be estimated using SLR.
Current ILRS Tracking Statistics:
| Satellite | Site Name | Station | Start Date | End Date | No. Passes | No. Points |
|---|---|---|---|---|---|---|
| ETS-8 | Changchun | 7237 | 05-Jun-2007 | 13-Mar-2008 | 35 | 168 |
| ETS-8 | Koganei | 7308 | 11-Mar-2007 | 15-Jul-2010 | 96 | 1,175 |
| ETS-8 | Mount Stromlo | 7825 | 13-Mar-2007 | 01-Jul-2010 | 61 | 596 |
| ETS-8 | Tanegashima | 7358 | 26-Apr-2007 | 03-Dec-2009 | 126 | 668 |
| ETS-8 | Yarragadee | 7090 | 10-Mar-2007 | 29-Jul-2010 | 460 | 1,877 |
ETS-8 Mission Support Request Form (October 2003):
Name: ETS-8
Host: JAXA
Primary Technical Contact: Akio YAMAMOTO
Alternate Technical Contact: Mikio SAWABE
Technical Contact Mailing Address: 2-1-1 Sengen, Tsukuba city,
IBARAKI, Japan
Technical Contact Fax: +81 29 868 2990
Technical Contact Email: sawabe.mikio@jaxa.jp
Technical Web Address: http://god.tksc.jaxa.jp/
Primary Science Contact: Akio YAMAMOTO
Alternate Science Contact: Mikio SAWABE
Science Contact Mailing Address: 2-1-1 Sengen, Tsukuba city, IBARAKI,
Japan
Science Contact Fax: +81 29 868 2990
Science Contact Email: sawabe.mikio@jaxa.jp
Science Web Address: TBD
Mission objectives: JAXA carries out the experiment of satellite
based augmentation using ETS-VIII. We called it
"HAC experiment". The HAC experiment will be performed
to operate the positioning system including ETS-VIII and
GPS satellites. ETS-VIII and GPS satellite orbits and clocks are
estimated on a real-time basis. In this experiment,
JAXA plans study techniques as below:
- On board atomic clock performance evaluation technique
- Clock synchronization technique between satellite and ground station Ranging error estimation technique
- Precise real-time orbit determination technique for geostationary satellite
- Positioning accuracy by different chip rate
- Navigation signal relay technique using satellite (so called Bent-pipe)
- Real-time system operation technique
Mission role: The ETS-VIII SLR mission objectives are as follows:
- To determine orbit of ETS-VIII precisely and also used for the evaluation of orbit determination accuracy using ETS-VIII navigation data.
- To evaluate time synchronization between ground clock and on-board clock.
- To establish SLR tracking technique for geostationary satellite
Launch date: Winter-2004
Mission duration: 3 years
Altitude: Geostationary Orbit (GEO) Longitude 146 degE
Inclination: N/A
Eccentricity: N/A
Tracking schedule: It will be able to track ETS-VIII after 40days
launch. Tracking information will be notified to
registered station by e-mail or web.
Spatial coverage: The Asiatic Continent and Pacific Ocean area
(WPLTN and Hawaii)
Temporal coverage: All times
Data accuracy: Centimeter ranging accuracy
Coordinator: ILRS
Priority: Primary
Data source: JAXA
POD source: ETS-VIII Navigation message such as GPS signal
Analysis Center: JAXA
NPT time span: 300 seconds
Tracking requests: WPLTN, Hawaii
Delivery time: Nominal Operation
Array info: The array consists of 36 corner cubes, which are 4.1
cm in diameter respectively. The array
structure is aluminum alloy and the corner cubes are constrained
to allow for the differential thermal expansion of the
structure and the quartz corner cubes. The array assembly weighs
less than 3100 g. The array is 26 cm length, 30 cm
width and 5.5 cm height (see ETS-VIII SLR Tracking Standards or
web).
Technical contact for array info: Akinobu SUZUKI
Technical array contact number: suzuki.akinobu@jaxa.jp/+81 29 868
2623
Comments: More detailed information is shown in the ETS-VIII SLR Tracking Standards. This document will be distributed to the related station 1 year before ETS-VIII launch.
