Thai Remote Sensing Satellite System
Dr. Suvit Vibulsresth, Waraporn Suchaichit
The National Research Council of Thailand (NRCT)
196 Phaholyothin Road, Chatuchak
Bangkok 10900, Thailand
Tel. 662-5790116 Fax. 662-5613035
Abstract
In October 1994, the Ministry of Science, Technology and Environment (MOSTE) concluded a Memorandum of Understanding (MOU) with the Canadian Space Agency for cooperation in space technology and applications. An earth observation small sat mission, as the first cooperative mission under the MOU recently received the Thai Government approval. MOSTE, through its technical authority in the National Research Council of Thailand (NRCT) will own and operate the satellite system. This will be the first satellite to operate in an orbit dedicated to the equatorial regions. The first operational mission will extend the information available to both scientific and operational users and will augment data currently available from the Landsat series of spacecraft. This paper will present an overall system concept for the Smallsat Program, which will operate over its 5 years lift span.
1. System Overview
The purpose of the system is the provision of regularly updated multispectral image I data on an operational basis. Output from the system will take the form of image data products which can be distributed to users who will apply the data, either directly or after further processing, to the management of resources.
2. System Architecture
The essentilal elements of the Thai Remote Sensing Satellite System are : I. the Ground Segment .2. the Space Segment
-
the Launch Segment
- the Space Segment
- the Launch Segment
2.1 System Description and Performance
2.1.1 Overall System Description
The performance parameters of the Thai Remote Sensing Satellite System are summarized in the following tables.
Table 2.1.1-1 Mission Performance
| Mission Life |
5 years |
| Orbit Type |
73 orbits/5 days Multi -sun-syschronous |
| Orbital Period |
97 minutes |
| Orbit Inclination |
28 degrees |
| Orbital Altitude |
600 km |
| Coverage Repeat |
Every 5 days |
| Illumination Repeat |
49 days |
| Command Up link |
S-Band: 2 kbps |
| Telemetry Downlink |
S-Band: Direct 2/4 kbps Playback 32/128 kbps |
| Data Downlink |
X-Band: < 85 Mbps |
TABLE 2.1.1-2 Temporal Performance
| Parameter |
Value |
| Revisit Time |
Twice every 5 days |
| Accessibility Region |
29.60N to 29.60S |
| Maximum Imaging Capability |
10 minutes/orbits |
| Useable opportunities per year |
63 |
Table 2.1.1-3 Spatial Performance
| Parameter |
Value |
| Swath Width |
185 km imaged swath which is selectable within a 275 km accessibility region. |
| Across Track Resolution |
30 m (nadir) |
| Along Track Resolution |
30 m (madir) |
| Geometric Distortion |
< 1/2 pixel Band to |
| Band Registration |
< 1 pixel |
| Image Locations |
< 5 km |
TABLE 2.1.1-4 Spectral Performance
| Parameter |
Value |
| Spectral Bandwidths: |
|
| Blue |
0.45 to 0.52 mm+01 |
| Green |
0.52 to 0.60 mm+01 |
| Red |
0.63 to 0.69 mm+01 |
| NIR |
0.76 to 0.90 mm+01 |
