| definition |
- TiungSat-1 is Malaysia's first national microsatellite. It was designed and developed in a collaborative effort between the Malaysian government, under the government appointed company ATSB [Astronautic Technology (Malaysia) Sdn. Bdh.] of Kuala Lumpur, and SSTL (Surrey Satellite Technology Ltd.) of Surrey, UK. In the view of the Malaysian government, the satellite development program was seen as an impetus for expanding Malaysia's capability in the area of high-technology industry. The first satellite was named "Tiung" after a beautiful small singing bird in Malaysia. Astronautic Technology Sdn. Bhd. (ATSB) is a research and development organization, which was formed in 1995 by the government of Malaysia. The TiungSat-1 specific applications are in the following fields:
* Collection of imagery for environmental and meteorological use * Digital S&F (Store & Forward) communications * Technology demonstration * Space science * Amateur radio access Spacecraft: The TiungSat-1 S/C structure comprises eleven module trays used to house the electronics for the bus and payload systems. The box-like spacecraft has a size of 690 mm x 360 mm x 360 mm; it is three-axis stabilized using a gravity-gradient boom (6 m boom with tip mass), two 3-axis magnetorquers, and a momentum wheel. Attitude is sensed by two 3-axis magnetometers and by two-axis analog sun sensors. In addition, there are UED (Underneath Earth Detector) and SOD (Sun Overhead Detector). The pointing knowledge is in roll and pitch and in yaw (3 sigma values). The S/C power is 35 W per panel, provided by four surface-mounted GaAs solar panels and by a 10-cell NiCd battery (7 Ah). The power subsystem provides regulated voltage supplies at +5V and 10V along with an unregulated supply which fluctuates between 12-14 V. Autonomous functions, safe modes and data are handled by two OBCs (On-Board Computer), OBC-186 and OBC-386. Onboard data handling via a CAN (Controller Area Network) between platform and payloads. The onboard data storage capacity is 1 Gbit. The S/C mass is 50 kg (platform = 35 kg, payload = 15 kg). The nominal design life is three years. RF communications: TiungSat uses conventional AMSAT frequencies (Malaysian Oscar-46), thereby giving amateur radio operators access to its data (imagery and communication capabilities). The microsatellite features an AX.25 protocol store-and-forward PACSAT protocol suite communications system. The uplink is in VHF-band with a data rate of 9.6 kbit/s; three receivers are used: Rx1 operates at 144.46 MHz, Rx2 and Rx3 operate at 145.86 145.925 MHz, selectable. The downlink is dual-redundant in UHF-band (435 to 438 MHz range with 437.300, 437.325, 437.350, 437.375 MHz, selectable) with data rates of 9.6, and 38.4 kbit/s (experimentally at 76.8 kit/s). An error-protected digital packet communications protocol is used. All spacecraft operations are performed at ATSB in Kuala Lumpur. TiungSat-1 was launched Sept. 26, 2000 on a Dnepr-1 vehicle along with other satellites (the other payloads were: SaudiSat-1A/-1B of SISR (Saudi Institute for Space Research), UniSat of the University of Rome, and MegSat-1 of the MegSat Space Division of "Gruppo Meggiorin," Bresia, Italy) from the Baikonur Cosmodrome, Kazakhstan. Orbit: Circular orbit, altitude = 650 km, inclination = 64, period = 97 minutes. Spacecraft operations are carried out at ATSB's Mission Control Station located at the Universiti Kebangsaan Malaysia, Bangi, Selangor. The satellite has also been used in a number of educational activities ranging from the physical sciences to the humanities. Operational status of TiungSat-1 as of 2004: The payload was fully operational well beyond its design life of three years. However, since Jan. 2004, the payload is only being operated intermittently to reduce the power consumption of the battery. Sensor/experiment complement (MSEIS, MEIS, S&F, CEDEX): MSEIS (Multi-Spectral Earth Imaging System). MSEIS is a NAC (Narrow Angle Camera), a multispectral system of three cameras (green, red and near-infrared) in parallel, each with a 75 mm focal length optic and 100 mm aperture diameter. The NAC system provides a 78 m ground spatial resolution in three spectral bands: 510-590 nm, 610-690 nm and 810-890 nm (green, red, and near infrared). A two-dimensional CCD staring array detector with 1024 x 1024 pixels is used providing snapshot imagery of scene size 78 km x 78 km. Up to four contiguous images can be collected along the flight path. The data are digitized to 8 bits radiometric resolution (256 levels). MEIS (Metrological Earth Imaging System). MEIS is a single-band WAC (Wide Angle Camera) system with 6.5 mm focal length optics. It provides NIR imagery (810-890 nm) with a 900 m spatial resolution. The CCD area array detector has a size of 1024 x 1024 elements (pixels) for snapshot observations. Data are quantized to 8 bits radiometric resolution. An image has the size of 900 km x 900 km. The data is being used for meteorological applications. S&F (Digital Store & Forward Communications). The subsystem provides global, frequency-agile, communications for any form of digitized data: e-mail, voice-mail, scientific data exchange, fax, imagery, or even Internet mail for remote regions. The low cost and direct access offered by the TiungSat-1 microsatellite in orbit also makes it ideal for use by scientists, engineers and students based in institutes, universities and even schools throughout the world. - DSPE (Digital Signal Processing Experiment). The DSPE consists of a TM320C31 low power DSP suitable for special or general purpose signal processing tasks on LEO satellites. The VHF scanner operates in the 140-150 MHz range. A built-in FSK decoder is used. The system is capable to detect signals from a pre-set signal strength threshold within selected bar. DSP can be used for processing audio transmission for rebroadcast. CEDEX (Cosmic Ray Energy Deposition Experiment). The objective of CEDEX is to characterize the TiungSat-1 orbit radiation environment in terms of the observed particle LET (Linear Energy Transfer) spectrum at the spacecraft. The primary sensor consists of a 30mm x 30mm PIN diode detector 300 microns in depth, housed in a separate screened aluminium unit mounted on the CEDEX module box (three area PIN-diode detectors are mounted in a "telescopic" arrangement; hence, information pertaining to directions of the energy particles detected can be derived.). This is connected to a charge amplifier and a pulse-shaping circuit which, in turn, are connected to an event-driven, hardware-logic controlled pulse-height multi-channel analyzer. CEDEX is controlled autonomously by a CAN-microcontroller with its own data-storage RAM and built-in data-compression software. This sends data to an internal CAN-controller which formats and sends them on to the primary OBC via the spacecraft's CAN (Controlled Area Network) bus. CEDEX is a multichannel analyzer with 512 channels and a 0.5 pC (picocoulomb) charge resolution. The instrument charge range is between 0.2 -24 pC, equivalent to a normal incidence particle LET range of about 60 - 7500 MeV cm2 g-1 (200,000 particles/s). The CEDEX data obtained are comparable directly with such instruments as CREDO-II flown on STRV-1c (launch Nov. 16, 2000) and CRE (Cosmic Ray Experiment) flown on KitSat-1 (launch Aug. 10, 1992) and PoSat-1 (launch Sept. 26, 1993). Experimental Microsatellite GPS, an SSTL/ESA collaboration. An advanced 12-channel GPS receiver with two GPS patch antennas is installed for several objectives: 1) onboard generation of Keplerian orbital elements (NORAD experiment, this was first performed on PoSat), 2) onboard navigation, attitude, and timing services, and 3) refractive sounding of the ionosphere. The instrument is primarily used for orbit and position determination and for precise onboard timing services. In parallel, the instrument is also employed for refractive ionospheric monitoring. The TEC (Total Electron Content) occultation observations of the instrument provide slant range measurements which can be converted into vertical profiles. Information provided by: http://www.eoPortal.org Group: Platform_Details Entry_ID: TIUNGSAT-1 Group: Platform_Identification Platform_Category: Earth Observation Satellites Short_Name: TIUNGSAT-1 End_Group Group: Synonymous_Platform_Names Short_Name: MySat-1 Short_Name: Oscar-46 Short_Name: MO-46 End_Group Group: Platform_Associated_Instruments Short_Name: CCD IMAGER Short_Name: CAMERAS End_Group Group: Orbit Orbit_Altitude: 650 Orbit_Inclination: 64.6 Period: 97.1 Perigee: 605.3 Apogee: 647 Orbit_Type: LEO > Low Earth Orbit > Polar Sun-Synchronous End_Group Creation_Date: 2008-06-19 Online_Resource: http://directory.eoportal.org/get_announce.php?an_id=7470 Online_Resource: http://www.sstl.co.uk/ Group: Platform_Logistics Launch_Date: 2000-09-26 Launch_Site: Baikonur Cosmodrome, Tyuratam, Russia Primary_Sponsor: Malaysia Primary_Sponsor: Surrey Satellite Technology Ltd. (SSTL) End_Group End_Group
|
