[url="http://www.isro.org/rep2010/Index.htm"]ISRO 2009-10 Annual Report[/url]
Excertpts:
Excertpts:
Quote:Forthcoming Satellites
GSAT-4
GSAT-4, envisaged as a technology demonstrator, carries a communication payload consisting of a multi-beam Ka-band bent pipe, regenerative transponder and a navigation payload in C, L1 and L5 bands.
[center]GSAT-4 ready to enter CATVAC[/center] GSAT-4 having propulsion system with four stationary plasma thrusters, Bus Management Unit (BMU), miniaturised dynamically tuned gyros, 36 AH Lithium ion battery, 70 V bus for Ka band TWTAs, on-board structural dynamic vibration beam accelerometer, are some of the new technologies developed for the mission. The satellite weighs around 2200 kg and has a payload power of 1600W. GSAT-4 will be positioned at 82 deg East longitude.
The satellite integration and test activities are in advanced stage. Spacecraft closed mode IST has been completed. The thermovacuum tests have been completed successfully and the Spacecraft Dynamic and CATF tests are in progress. The spacecraft is almost ready for shipment to SDSC SHAR.
[center]GSAT-4 plasma thruster mounted on satellite structure[/center] AVANTI HYLAS
Hylas is being developed and built for Avanti Screenmedia, UK jointly with EADS-Astrium under a contract through ANTRIX. EADS Astrium is the prime contractor in charge of overall programme management and will build the communications payload. ANTRIX, ISRO will build the satellite bus, based on the flight proven I-2K model with a lift off mass of around 2550 kg and payload power of 2000 W, integrate and test the satellite. ISRO will also be in charge of Launch and Early Orbit operations. Hylas is designed for an operational lifetime of 15 years and exploits generic, flexible payload equipment.
Avanti Hylas payloads are:
During the year, the satellite bus elements were realised. Integration Readiness Review was completed with the participation of M/s. Astrium. All bus elements except BMU and Inertial Systems have been integrated with the spacecraft. Disassembled mode IST is in progress. The satellite will be ready for shipment by mid 2010.
- Ku-Band transponders covering entire Western Europe through 15m deployable reflector
- Ka-band transponders providing eight spot beams through 2.6m x 1.6m
[center]Hylas Spacecraft during integration[/center] GSAT-5 PRIME
GSAT-5P is being planned as replacement for INSAT-3E and will carry 24 Normal C Band and 12 Extended C Band transponders with India Coverage. The spacecraft will be positioned at 55 deg East longitude with a mission life of 12 years.
The spacecraft weighs 2330 kg and payload power requirement is 1700W. Spacecraft configuration and equipment panel layouts are finalised. Payload subsystems and other subsystem packages are under advanced stage of realisation.
in uplink and downlink over Asia, Africa and Eastern Europe as well as zonal coverage with a minimum of 35 dBW EIRP.
The spacecraft has a mission life of 12 years. The spacecraft weighs 2330 kg and has a power generation capability of 2000W. The layouts for all equipment panels are finalised. Fabrication of bus system elements have been initiated.
GSAT-6/1NSAT-4E
The primary goal of GSAT-6/INSAT-4E, which is a Multimedia broadcast satellite, is to cater to the consumer requirements of providing entertainment and information services to vehicles through Digital Multimedia consoles and to the Multimedia mobile Phones. The satellite carries a 5 spot beam BSS and 5 spot beam MSS. It will be positioned at 83 deg East longitude with a mission life of 12 years.
The satellite configuration is based on I-2K bus system with a liftoff mass of 2200 kg and payload power of 2300W. Power system is configured with a single bus providing 70V regulated bus for the TWTAs and 42 V regulated bus for the mainframe systems and other payload elements. Multi-junction solar cells for power generation and Lithium-Ion batteries for power storage have been used.
An indigenously developed Unfurlable Antenna(UFA) which provides five beams to cover the entire Indian land mass is the new element in the satellite. The scaled down model (2m dia) of the UFA with the same design and fabrication features has been developed to evaluate its RF performance. Fabrication of all platform systems hardware is in progress and payload subsystem elements are available. The launch is planned on-board GSLV during 2010.
GSAT-7/1NSAT-4F
GSAT-7 is a multi-band satellite carrying payloads in UHF, S-band, C-band and Ku-band. It is planned to be launched during 2011 onboard GSLV and positioned at 74 deg East. The satellite weighs 2330 kg with a payload power of 2000W and mission life of 9 years. Structural configuration of the satellite has been finalised and the layout work is completed, detailed design of UHF antenna mechanism is in progress and antenna shock analysis completed. The platform systems are under fabrication and payload subsystem procurement is in progress.
GSAT -8/1NSAT-4G
GSAT-8/INSAT-4G is a Ku-band satellite carrying 18 Ku band transponders. It will also carry a GPS Aided Geo Augmented Navigation (GAGAN) payload. The satellite is planned to be launched during 2010 with a mission life of 12 years and positioned at 55 deg E longitude. This I-3K satellite with a lift-off mass of 3150 kg and a payload power of 5300W will be launched on board ARIANE-5. Fabrication of bus systems is in an advanced stage.
GSAT-12
GSAT-12 is being realised as replacement INSAT-3B. Realisation of various sub systems is progressing satisfactorily. The satellite will carry 12 Extended C-band transponders and will be positioned at 83 deg East longitude with a mission life of 7 years. The bus system is based on I-1K platform with ASIC based BMU and 64 Ah Li-ion batteries. The satellite weighs 1375 kg with a payload power of 550W.
During the current year, the Configuration Design Review was completed and all layouts and interfaces were finalised. Payload realisation is in progress. Fabrication of bus systems is in progress and launch is planned onboard PSLV during 2010.
GSAT-9
GSAT-9 will carry 6 C band and 24 Ku band transponders with India coverage beam. The satellite is planned to be launched during 2011-12 with a mission life of 12 years and positioned at 48 deg E longitude. This I-2K satellite has a liftoff mass of 2330 kg and payload power of 2300W.
GSAT-10
GSAT-I0 will carry 12 Normal C-band, 12 Extended C-band and 12 Ku-band transponders. It will also carry GPS Aided Geo Augmented Navigation (GAGAN) payload. The satellite is planned to be launched during 2011 with a mission life of 15 years and positioned at 83 deg East longitude. This I-3K satellite with liftoff mass of 3435 kg and payload power of 4500 W will be launched on board ARIANE-5.
Configuration of both platform systems and payload has been finalised and procurement action for long lead items has been initiated. Fabrication of platform systems is already initiated.
INSAT-3D
INSAT-3D, a meteorological satellite, carries a 6-Channel VHRR and a 19 channel Sounder. VHRR provides information in the visible (0.6) and near infrared (1.6) with 1 km resolution; MWIR (3.9) with 4 km resolution; Water Vapour (6.7) with 8km resolution; and IR 10.8 and IR 12.0 with 4 km resolution. INSAT-3D Sounder has 18 infrared channels and a visible channel to help cloud detection during daytime.
Many geophysical parameters such as the Outgoing. Long wave Radiation (OLR), Quantitative Precipitation Estimation (QPE), Sea Surface Temperature (SST), Snow cover, Snow depth, Cloud Motion Vector, Water Vapor Wind (WVW), Upper Troposheric Humidity, Temperature, Humidity profile and Total Ozone, aerosols, etc., are expected to provide operational inputs for weather forecasting applications. The satellite has many new technology elements like star sensor, micro stepping Solar Array Drive Assembly (SADA) to reduce spacecraft disturbances and Bus Management Unit (BMU) for control and Telemetry /Telecommand function. It also incorporates new features of bi-annual rotation and image and mirror motion compensation for improved performance of the meteorological payloads.
The spacecraft weighs 2050 kg with power generation capability of 1200W. The subsystem fabrication is in advanced stage of realisation. FM Sounder payload testing is completed and FM Imager payload system level optimisation is in progress. Mainframe elements, structure along with north and south equipment panels are available. Many of the bus-system elements are in advanced stage of realisation and the launch is planned on-board GSLV in 2010-11.
SATELLITE NAVIGATION
GPS AIDED GEO AUGMENTED NAVIGATION (GAGAN)
The Indian Satellite Based Augmentation System (SBAS) is called GAGAN. The Technology Demonstration Phase (TDS) of GAGAN was successfully completed in August 2007. As apart of the TDS, eight Indian Reference Stations (INRESs) have been installed at eight Indian airports. They are linked to the Master Control Center (MCC) located at Kundanhalli near Bangalore. From MCC, the Indian Land Uplink Station (INLUS) transmits correction signals to the space segment having GAGAN navigation payload which translates these signals to the GPS LT bands for reception by a GPS SBAS receiver. In June 2009, the operational phase (FOP) of GAGAN was initiated. The GAGAN system is expected to be ready for testing in about 18 months.
The first GAGAN navigation payload has been fabricated and it is proposed to be flown on GSAT-4 which will be launched in 2010. Two more GAGAN payloads will be subsequently flown, one each on two geostationary satellites, GSAT-8 and GSAT-10. Preparation of sites for INRES installation and third INREE chain on TDS system is in progress.
INDIAN REGIONAL NAVIGATION SATELLITE SYSTEM (IRNSS)
IRNSS constellation consists of seven satellites. Three satellites will be placed in Geostationary orbit (GEO) at 34ðE, 83ðE & 131.5ðE and two satellites each will be placed in the Geosynchronous orbit (GSO) with equatorial crossing at 55ðE and 111.5ðE with an inclination of 29ð to the equator. Two spare satellites are also planned to be realised. IRNSS will have two types of signals, in L5 and S-Band. IRNSS provides two basic services a Standard Positioning Service (SPS) for common civilian users and a Restricted Service (RS) for special authorised users.
IRNSS Signal and Data structure have been prepared and reviewed. The signal and data structure has been prepared after extensive study by groups at the work centers.
[center]Indian Regional Navigation Satellite System (IRNSS)[/center] [center] [/center]
The civil construction work for the Navigation Control Centre at Bangalore and the Satellite Control Facility at Hassan is in progress. The navigation software for IRNSS is being indigenously developed at ISRO Satellite Centre. As a part of this activity, many modules have been developed and testing is in progress. Coverage Studies, Error Analysis, Up linking scheme for Navigation Parameters and Time Synchronisation have been carried out. Navigation Payload configuration is frozen and Preliminary Design Review (PDR) has been completed. The realisation of the Payload Engineering Model is progressing satisfactorily.
The spacecraft configuration has been finalised and the satellites of the constellation are being configured identically and each spacecraft weighs 1380 kg. Fabrication of six structural cylinders is completed. Most of the standard hardware is productionised. The spacecraft is basically configured with I-1K Bus to be compatible with launch onboard PSLV. After detailed analysis, it was found that it would be possible to launch two numbers of inclined orbit satellites in one flight of GSLV.