1. INTRODUCTION

Since launch of SPUTNIK-1 in 1957 satallite technology has progressed by leaps and bounds.

Satellite, in general, is any natural or artificial body moving around a celestial body. Earth and moon are common examples of sun and the earth respectively. An artificial satellite is a specialized wireless receiver transmitter that is launched by rocket and placed in an appropriate orbit around earth. Currently, there are around 3500 satellites revolving around the earth this no. is ever increasing.

The geostationary orbit is a orbit in which a satellite appears stationary relative to the earth. The earth station antenna pointed at a geostationary satellite, automatically follows it ,and elaborate tracking systems are not required.

The geostationary orbit lies in the equatorial plane meaning that the inclination is zero. The satellite orbit in the same direction as earth and same speed that as of earth and at distance of   36000Km from earth.  The periodic time P for the geostationary orbit is 23 hour, 56minute in mean solar time.

2. OVERVIEW

India recognized the potential of space science and technology for the socio-economic development of the society soon after the launch of Sputnik by erstwhile USSR in 1957. The Indian space efforts started in the sixties with the establishment of Thumba Equatorial Rocket Launching Station near Thiruvananthapuram for the investigation of ionosphere using sounding rockets. The Indian Space Research Organization (ISRO), was established in 1969 under the Department of Atomic Energy. The Government of India gave fillip to the space activities by formally setting up the Space Commission and the Department of Space (DOS) in June 1972 and ISRO was also brought under Department of Space.

Over the last three decades, India has achieved an enviable progress in the design, development and operation of space systems, as well as using the systems for vital services like telecommunication, television broadcasting, meteorology, disaster warning and natural resources survey and management. The space programme has become largely self-reliant with capability to design and build its own satellites for providing space services and to launch them using indigenously designed and developed launch vehicles.

2.1. GSLV

 The successful first test flight of Geo-synchronous Satellite Launch Vehicle (GSLV) from Sriharikota on April 18, 2001 was the most significant milestone of the Indian space program during the year 2001-02. The launch unequivocally demonstrated India’s capability to place satellites into geo-synchronous transfer orbits. India is among the six nations in the world to achieve such a capability. The launch of GSLV is the culmination of efforts of several DOS centres and other institutions that involved complex interfaces between scientific and technological disciplines, industries and research institutions.

2.2. PSLV-3

Another important milestone during the year was the successful flight of PSLV-C3 on October 22, 2001 from Sriharikota. In this fifth consecutively successful flight, PSLV placed three satellites — India’s Technology Experiment Satellite, TES, Belgian PROBA and German BIRD into their intended polar sun-synchronous orbit. The requirement of a higher orbit for the Belgian PROBA compared to other two satellites was successfully met by a flight maneuver. Both German and Belgium satellites were launched under commercial agreements. The flight has clearly established the reliability of PSLV for launching not only the Indian remote sensing satellites, but also, multiple satellites thus making it an attractive vehicle for the international space community to launch their satellites. PSLV is also planned to be used for a geo-synchronous transfer orbit mission for launching India’s METSAT in 2002-03.

2.3. IRS

The Indian remote sensing satellite system, IRS, which has the biggest constellation of satellites, continues to provide space–based remote sensing data for a number of applications in India and abroad. IRS system, at present, has five satellites, namely, IRS-1C, IRS-1D, IRS-P3, IRS-P4 (OCEANSAT) and Technology Experiment Satellite (TES). The TES which was successfully launched during the year has given further fillip to advance the technology of remote sensing in India. It has enabled testing new satellite hardware and demonstrating newer remote sensing techniques. It incorporates a panchromatic camera providing a spatial resolution of up to 1 m. Work on follow-on remote sensing satellites like RESOURCESAT, CARTOSAT-1 and CARTOSAT-2, is progressing well. They will not only continue the services of the present IRS satellites but also enhance the service capabilities.

The remote sensing applications continue to expand to several new areas; the data has been used to assess damage due to floods, earthquakes, etc and for helping in relief operations.

The announcement of Remote Sensing Data Policy (RSDP) during the year will help to streamline the availability of remote sensing data from Indian and foreign satellites to users in India.

2.4. CRYOGENIC SAMPLER

In the field of space sciences, the cryogenic sampler that had been developed by ISRO for Geosphere-Biosphere Programme, has been used to detect micro-organisms in the stratosphere, which could have far reaching implications on the understanding of the origin of life on earth. Detailed analyses of the samples collected are now going on in scientific research laboratories in India and abroad. Educational and research institutions in India continue to participate in the space programme taking up projects under the Sponsored Research scheme of DOS. During the year, 22 new projects were initiated under the scheme. The task team constituted to study the feasibility and scientific objectives for undertaking an unmanned mission to the moon has made substantial progress in their work.

2.5. SPACE INDIA

India continues to pursue active co-operation with several nations. During the year, Phase-B in-house publication "Space India’’ and other publications, telecast of major events like launch of GSLV and PSLV, arranging exhibitions, etc. During the year two media workshops were conducted to familiarise the media on the nuances involved in development and operation of space systems and their applications.

In the area of human resources, new initiatives have been undertaken to recruit and retain talented youngsters to serve the Indian space programme. A live register of Doctorates has been opened so as to select qualified engineers. Campus recruitment of Post-Graduates has also been continued during the year. study of the Indo-French joint satellite mission Megha-Tropiques has been initiated. India has signed the international charter on space and major disasters that envisages use of space systems in the event of natural or technological disasters.

The launch of two satellites - one of Belgium and another of Germany - on board PSLV marks an important event during the year under commercial marketing of India’s space capabilities. Data from IRS satellites continue to be received by several ground stations worldwide. The lease agreement of transponders on board INSAT-2E to INTELSAT has continued.

3.   GEO-STATIONARY SATELLITE SERVICES

The Geo-stationary Satellites which are placed in an orbit, about 36,000 km over the equator are used for telecommunication, television broadcasting and meteorological services. India established the geo-stationary satellite system, namely, Indian National Satellite (INSAT) system in 1983.

The INSAT system for telecommunication, television broadcasting and meteorology has received further boost during the year with the successful launch of INSAT-3C on January 24, 2002. INSAT-3C will not only augment the present INSAT system but also continue the services of some of the satellites that need to be phased out at the end of their mission life. INSAT is one of the largest domestic communication satellite systems in the world with five satellites, INSAT-2C, INSAT-2DT, INSAT-2E, INSAT-3B and INSAT-3C. Three more satellites, INSAT-3A, INSAT-3D and INSAT-3E are now in various stages of design, development and testing. The INSAT system also includes a few transponders leased from other agencies for meeting the current demands.

Planning of INSAT-4 series of satellites has been initiated based on detailed discussions with the various users. Seven satellites are proposed in the INSAT-4 series. With a view to enhance the INSAT system, both in terms of the transponder capacity and addition of newer services, experimental communication satellites, GSATs, are being built, which are launched during the developmental test flights of GSLV. GSAT-1 has already been launched and GSAT-2 is now under fabrication and testing. An exclusive satellite for meteorological services, METSAT is in an advanced stage of development.

Besides the use of INSAT for telecommunication, broadcasting and meteorological services, emphasis is being given for using the system for grassroots level applications like developmental communication and satellite-based training. New initiatives have been taken for using INSAT for introduction of tele-medicine to make speciality treatment accessible to the population in remote areas.

Beside these satellites, INSAT-1D which was launched in June 1990, is used for meteorological imaging and a few other services even after eleven years of operation. INSAT-2B launched in July 1993 which was decommissioned from regular services during the year, is still used for Satellite Aided Search and Rescue and Data Relay Services and two of its transponders are used for scientific experiments.

4. SATELLITES IN SERVICE

4.1.INSAT-2C

INSAT-2C, which was launched on December 7, 1995 is located at 93.5 degree east longitude.  INSAT-2DT: To partly augment the capacity of the INSAT system consequent to the loss of INSAT-2D (in October, 1997), an in-orbit satellite, ARABSAT-1C was procured from ARABSAT Organisation, a regional inter-governmental satellite consortium of Arab States. The satellite, designated as INSAT-2DT, is located at 55 degree east.

4.2.INSAT-2E

INSAT-2E was launched on April 03, 1999. It is located at 83 degree east longitude. Under an agreement with the International Telecommunications Satellite organisation (INTELSAT), eleven 36 MHz equivalent units of C-band capacity on INSAT-2E have been leased to INTELSAT under a commercial agreement.  

4.3.INSAT-3B

 INSAT-3B, the first satellite launched in the INSAT-3 series on March 22, 2000 is located along with INSAT-2E at 83 degree east longitude.

4.4.INSAT-3C 

One of the major accomplishments during the year was the realisation of  INSAT-3C, and its launch on board an Ariane-4 launch vehicle on January 24, 2002. INSAT-3C is located at 74 degree east longitude.

           Fig 4.1                                                                 Fig. 4.2

INSAT-3C S-band MSS Wide          INSAT-3C FSS C-band and BSS S-band

 Coverage                                                        India Coverage

                        4.3 INSAT-3C Shaped-Beam Antenna

 The satellite, after undergoing orbit raising operations and deployment of all appendages like the antenna and solar arrays is now under commissioning.

4.5.PAYLOADS ON INSAT-3 SATELLITES IN SERVICE:

5. FORTHCOMING SATELLITES

5.1.INSAT-3 SERIES 

INSAT-3 Series: Three more satellites in the INSAT-3 series — INSAT-3A, INSAT-3E and INSAT-3D are planned.

During the year, besides preparing INSAT-3C for its launch in January 2002, thermal design of INSAT-3A spacecraft was completed. Fabrication, inspection and secondary treatment of solar array deployment and antenna deployment mechanism components have also been completed. Sail-boom deployment mechanism components, TTC base band flight hardware and VHRR payload elements, have been realized. Assembly and integration of communication payload and assembly of south panel are in progress.

Fig 5.1 INSAT-3C in the Assembly Hall

Assembly of flight structure of INSAT-3E and preliminary thermal design, and configuration of deployable appendages have been completed. Structural design of INSAT-3D is in progress and thermal analysis of imager and sounder cooler for the satellite has been completed.

5.2. METSAT

METSAT is an exclusive meteorological satellite to be flown on PSLV. It will support the India Meteorological Department by providing meteorological services from geostationary orbit, including Cyclone Warning Dissemination Services, Meteorological

Fig. 5.2  METSAT

Data Collection and Weather Imagery on a continuous basis. The meteorological payload on METSAT comprises a 3-band VHRR instrument for providing imageries in visible, thermal IR and water vapour bands and a weather data relay transponder.

During the year, assembly of flight structure of METSAT has been completed. North, south and earth view decks have been realised. Thermal design has been completed. VHRR cooler housing has been fabricated. Fabrication of solar array mechanism is nearing completion. All control simulations have been completed.

5.3. EXPERIMENTAL SATELLITES – GSAT

GSAT’s are experimental satellites which are launched during the developmental test flights of India’s Geo-synchronous Satellite Launch Vehicle (GSLV).

5.3.1. GSAT-1

The first satellite, GSAT-1 was launched by the first developmental GSLV flight in April 2001. It carries two S-band transponders for Digital Audio Broadcast (DAB) and three Normal C-band transponders to demonstrate new applications including digital sound broadcasting, Internet services, distance education, It carries two S-band transponders for Digital Audio Broadcast (DAB) and three Normal C-band transponders to demonstrate new applications including digital sound broadcasting, Internet services, distance education,

developmental communications and compressed digital TV services.

Fig 5.3 GSAT-1 in Space

An artist concept of GSAT-1 was launched by GSLV-D1 in an orbit of 181-km perigee and 32,051 km apogee with an inclination of 19.2 degree with respect to achieve the final geo-stationary orbit. In its present near-geo-synchronous orbit, all operations like deployment of antenna, solar array and the solar sail were successfully completed and GSAT-1 was put in 3-axis stabilisation mode using momentum wheels.

All new spacecraft technology elements that were flown on GSAT-1 have been evaluated. These include (i) Fast Recovery Star Sensor (FRSS) which provides enhanced accuracy of measuring satellite orientation and for quick earth-lock recovery in case of loss of lock, (ii) a new earth sensor using pyro electric detectors, (iii) an alternate strategy for orbit raising using a combination of four 22 Newton thrusters (iv) thermal control using heat pipes (v) new technique of power management through charger arrays for improving the overall efficiency of power systems (vi) orbit raising using perigee firing strategy and (vii) 10 Newton reaction n control thrusters.

When GSAT-1 is within the radio visibility of INSAT Master Control Facility (MCF), Hassan, it is being used for conducting several spacecraft operations experiments and configuring the spacecraft for unattended mode of operation. Development and equatorial plane. A minor shortfall of 0.6 percent in the velocity of injection of the satellite resulted in a reduction of orbital apogee of the satellite while the perigee and inclination were close to targeted values. Through a series of orbit manoeuvres, the orbit of GSAT-1 was raised close to near-geo-synchronous orbit with an apogee of 35,665 km, perigee of 33,806 km and inclination of 0.997 degree. It has an 4 orbital period of 23 hr 2 minutes. During the orbit raising operations, consumption of propellant on board the satellite was more than planned resulting in a shortage of about 10 kg to implementation of a special software for the on-board AOCE computer to carry out momentum dumping automatically has been specially developed and implemented on the satellite.

The Communication Payload of GSAT-1 consisting of three normal C-band transponders, and two CXS transponders have also been tested and all transponders have worked normally. The Antenna Positioner Mechanism (APM) which can switch the antenna beam between two locations has also been tested. A few experiments like Digital Video Transmission, Digital Audio Transmission, Internet Broadcast System have also been carried out.

Fig 5.4 GSAT 1 ON ASSEMBLY JIG

5.3.2. GSAT 2

GSAT-2 to be launched by the second developmental flight, GSLV-D2, will have the following payloads:

• Four Channel C-band FSS transponder with 15W SSPA to meet an eirp of 36 dBW at EOC for FSS Services.
• Two Channel Ku-band FSS Transponder with 70 W TWTA to meet an eirp of 42 Dbw at EOC.

MSS transponder consisting of forward channel in S-band with 70 W TWTA and a return channel in C-band with 14W/5W SSPA to meet the eirp of 37 dBW for forward link and 30 dBW for return link respectively.

GSAT-2 will also carry instruments to conduct experiments like total radiation dose monitor, surface charge potential monitor, coherent radio beacon experiment and solar X-ray spectrometer. During the year, assembly of flight structure and dynamic analysis have been completed. Fabrication of solar array deployment mechanism components, C-band reflector components have been completed. All control simulations have been completed.

GSAT-3 and GSAT-4 are under planning. One of these satellites is proposed to carry Ka-band regenerative transponders and a large unfurlable antenna and besides other new technologies.

5.4.INSAT-4 SERIES

Planning of INSAT-4 series of satellites has been initiated. It is proposed to have seven satellites in the series. INSAT-4A through INSAT-4G with INSAT-4D as a spare. The transponder capacity has been worked out after a detailed evaluation of the projected requirements by the various users. It is expected that by 2007, INSAT will have 251 transponders in various bands catering to a demand of up to 11 GBPS capacity.

6. MASTER CONTROL FACILITY (MCF)

Master Control Facility (MCF) at Hassan in Karnataka monitors and controls all the geo-stationary satellites of ISRO including initial orbit raising phase. At present MCF controls – INSAT-2C, INSAT-2E, INSAT-3B, INSAT-3C and INSAT-2DT. Three satellites in inclined orbit – INSAT-1D, INSAT-2A and INSAT-2B are also being monitored. MCF is monitoring GSAT-1 whenever the satellite is within its visibility.

Fig. 6.1 Satellite Control Earth Station at MCF, Hassans

MCF has Spacecraft Control Centre, Telemetry Tracking and Command Network, and associated support facilities. MCF closely interacts with user agencies for payload operations. MCF is equipped with Satellite Control Earth Stations (SCES) with a variety of antenna’s to suit the mission requirements. It has a computer network with servers and workstations for spacecraft mission operations. A multi-mission spacecraft health monitoring and control software has been implemented on this network. Besides supporting INSAT missions, MCF also provides orbit-raising support, in-orbit payload testing, and interference testing services to international missions under commercial contracts of Antrix.

7.INSAT SERVICES

7.1. TELECOMMUNICATIONS

INSAT system continues to support various communication services in the country. A total of 548 telecommunication terminals of various sizes and capabilities are now operating in the INSAT telecommunications network, providing 5,100 two-way speech circuits or equivalent over 166 routes. These include 140 fixed and captive, 20 transportable, 30 other government users and 358 Multi-Channels Per Carrier Very Small Aperture Terminals (MCPC-VSATs) and 23 Private VSAT hubs. Another 400 earth stations are in various stages of implementation in the DOT network. In the National Informatics Centre Network (NICNET) over 800 microterminals are operating. Twelve closed user group 64 kbps data networks are operating through INSAT extended C-band transponders.

About 259 VSATs are operating under the Remote Area Business Management Network.Under Remote and Rural Area Communications using MCPC-VSATs, 245 VSATs are operating in the DOT network and another 102 are being added. High speed VSAT Network (HVNET) terminals are being offered on lease for data-only terminal and for data and voice services. Seventeen long distance subscriber telephone terminals are operational and 20 more are under consideration. The Bangalore-Delhi digital network with two 34 Mbps streams has been commissioned. Augmentation of existing eight Mbps connectivities amongst four metropolitan cities is planned by using digital channel multiplexing equipment.

Captive satellite-based networks for National Thermal Power Corporation (NTPC), Gas Authority of India Ltd (GAIL), Nuclear Power Corporation (NPC), Indian Telephone Industries (ITI), Oil and Natural Gas Commission (ONGC), National Fertilisers Limited (NFL) and Coal India Limited (CIL) are operational. A CIL earth station at Poonch has been commissioned. The National Stock Exchange (NSE) VSAT network in extended C-band is operational. A number of captive government networks are also working with INSAT. More organisations are in the process of implementing their own captive networks using INSAT capacity. DOT has licensed a few private operators to provide value-added services to the public using the extended C-band.

7.2. MOBILE SATELLITE SERVICES (MSAT)

The  Mobile  Satellite  (MSAT)  systems is intended to complement  

existing mobile communications  systems  such as those provided by cellular  radio  operators ,  radio  common carriers and telephone companies. Existing mobile services do not adequately cover many rural and remote areas.

The satellite to mobile links will use L-band  frequencies, the downlink frequencies being in range 1550  to 1559 MHZ , and uplink frequency 1626.5to  1660.5 MHZ. These bands are divided into sub-bands as allocated at the World Administrative Radio Conference  (WARC).

7.2.1. SERVICES  OFFERED BY MSAT

7.2.1.1: Mobile Radio Trunking Service (MRTS)

This is a mobile dispatch service similar to the terrestrial radio services presently available, but off course it offers wide area coverage not possible with the terrestrial systems. The services can be private or shared. In the private network, the base station will be owned and operated by the customer’s organization, while in the shared network, the base station will be shared amongst several customers with the service provider operating the station. Access to PSTN will be available only on a very restricted basis.

7.2.1.2:  Interconnected  Mobile Radio Service (IMRS)

        This is a radio service which connects users to PSTN  where access is not otherwise  available. Calls from mobile units will be forwarded through the MSAT to a gateway earth station , which connects up to  PSTN . In addition to mobile units, fixed stations installed in remote communities can also use this service.

7.2.1.3: Mobile Data Service(MDS)

This service is to provide two-way data links between mobile and fixed terminals and should be of particular interest  to the transportation industry. Some suggested services (MSAT, 1988)  are interactive two way digital messaging; vehicle dispatch and position location; data acquisition and control ; data broadcast; wide area paging and page alert ; automatic wide area vehicle monitoring; one way emergency signaling ; and electronic data inter exchange. It is foreseen that periodic communication of vehicle information and precoded  messages would provide position location, cargo monitoring, data collection and two way messaging. The mobile data terminal will be similar to the mobile transreceiver  with the addition of an alphanumeric display and a keypad or keyboard.

With the launch of INSAT-2C in December 1995, an S-band Mobile Satellite Service (MSS) was added to the INSAT system on an experimental basis. The following two classes of services were identified for MSS:

INSAT Mobile Telephony, which consists of low bit rate encoded voice, data and fax services using demand assigned SCPC channels, with mobile and portable (suit-case size) terminals. Five terminals have been installed as pre-operational service. The INSAT-MSS is targeted at land mobile and maritime users. The hub for INSAT-MSS services is located at Bangalore.

INSAT Reporting System, which consists of low bit rate one-way reporting service using shared channels with portable and hand-held terminals. This one-way messaging from a remote location to user-headquarters operates with the Delhi Earth Station (DES) of DOS as the Hub. Short messages from user terminals are relayed through the satellite to the Hub and are automatically forwarded to the respective user headquarters via Fax or data links. This reporting service is provided using small hand-held terminals. The network manager at the Hub keeps track of the destination addresses for the mobile user messages and forwards it through fax or data interfaces. There is a provision to attach a GPS receiver to the reporting terminal for position information.

7.3. TELEVISION

INSAT has been a major catalyst for the rapid expansion of television coverage in India. At present, 33 TV channels are operating through the C-band transponders of INSAT system as follows:

National networking service (DD-1), Metro service (DD-2) and Digital Satellite News Gathering (DSNG) service.

Regional services in Kerala, Karnataka, Jammu & Kashmir, Tamil Nadu, West Bengal, Andhra Pradesh, Gujarat, Uttar Pradesh, Assam, Maharashtra, Punjab, North-Eastern States, Himachal Pradesh, Rajasthan, Orissa, Bihar and Madhya Pradesh.

At present, 1,199 transmitters are working in the INSAT system out of which 1,104 transmitters (92 HPTs, 711 LPTs and 280 VLPTs) and 21 transposers are working in the DD-1 network and 90 TV Transmitters (39 HPTs, 45 LPTs and 6 VLPTs) are working in the DD-2 network. Three HPTs and two LPTs are used for other services.

7.3.1. Educational TV

An exclusive 24 hours Educational TV (Gyandarshan) is being operated by Doordarshan. Curriculum-based programmes are produced with active involvement of State educational administrators and teachers and programmes for school children are produced by the State Institutes of Educational Technology (SIET) — Marathi at Pune, Gujarati at Ahmedabad, Oriya at Bhubaneshwar and Telugu at Hyderabad — which are relayed by all transmitters in the concerned States. Hindi programmes are produced at State Institutes of Educational Technology at Delhi, Lucknow and Patna.

Programmes for university students are produced by Education Media Research Centres and Audio Visual Research Centres at different places. These programmes provide quality education within the reach of students in small towns and villages. Syllabus-based programmes for students enrolled in Indira Gandhi National Open University (IGNOU) are also relayed on this channel.

7.4. Satellite News Gathering and Dissemination

Satellite News Gathering using INSAT system enables real-time news coverages. Prasar Bharati is procuring Outdoor-Broadcast (OB) SNG terminals to cover important events in different locations for transmission via satellite to a central station at Delhi for rebroadcast over Doordarshan channels.

`Press Trust of India (PTI) is implementing a system to provide its news and information services at higher speed and increased volume and variety directly to a wider range of media and other users by utilising the broadcast facilities of INSAT. The project utilises a Radio Networking (RN) type of channel on one of the broadcast (CxS) transponders of the satellite. The PTI satellite news and facsimile dissemination project is working with 15 terminals (14 from PTI and one shared with AIR).

7.5. Radio Networking

Radio Networking (RN) through INSAT provides a reliable high-fidelity 10/15 kHz programme channels for national as well as regional networking. At present, 208 All India Radio (AIR) stations have been equipped with S-band receive terminals and 37 with C-band terminals. The RN system primarily uses CxS band transponder of INSAT in Single Channel Per Carrier (SCPC) mode. The RN carriers are injected at a low level into the high power CxS band transponders along with the TV carrier. The programmes received on these S-band receive terminals are rebroadcast by terrestrial transmitters. Interactive exchange of programmes also takes place between any two or more uplink stations.

There are 45 RN channels operating at present — 36 in S-band and 9 in C-band. Single channel captive uplink earth stations have been provided at 20 major programme producing centres (Srinagar, Ahmedabad, Bhopal, Cuttack, Patna, Guwahati, Shillong Thiruvananthapuram, Hyderabad, Bangalore, Jaipur, Shimla, Lucknow, Imphal, Kohima, Agartala, Aijwal, Chennai, Borivili and Hanagai). The captive earth station at Broadcasting House (BH), Mumbai is providing uplink of two Vividh Bharati channels.

The earth station at Broadcast House at Delhi, has been augmented to provide uplink for seven RN carriers in CxS band and four in CxC band. Four RN carriers are uplinked from Sikanderabad station of DOT for national networking.

C-band RN carriers are being received by 37 AIR stations. Transportable uplink terminals have been acquired by AIR for coverage of events taking place at remote locations and for relay of programmes directly from the spot via INSAT. AIR has also acquired DSNG RN terminals which are capable of uplinking CD quality music channel from any remote locations to a central place such as Delhi.

7.6. Training and Developmental Communication

Training and Developmental Communication Channel (TDCC) using INSAT is operational since 1995. It provides a one-way video and two-way audio system for interactive education. The teaching-end includes a simple studio and up-link terminal for transmitting live or pre-recorded lectures. The class-rooms located nation-wide receive lectures through simple dish antennas. They are also provided with telephones to interact with lecturers. The TDCC system is being used extensively by several State Governments for distance education, rural development, women and child development, Panchayat Raj and industrial training. Indira Gandhi National Open University (IGNOU) is one of the major users. The total network supports 1900 Direct Receive Terminals and they are being utilised for an average of 20 to 25 days a month. Over 250 programmes have been conducted during the year by various agencies and over 50,000 participants trained.

Andhra Pradesh is setting up an integrated satellite network for the purpose of distance education, health care and rural development. The network envisages Internet facilities to villages in Andhra Pradesh. It is proposed to utilize IP based Digital Transmission Technologies and DVB techniques

for establishing this network. DOS is providing consultancy and transponder capacity for the network.

In Gujarat, DOS has set up the up-link and studio with funding by State Government. The system is operational since August 2000. The Training programmes are being conducted regularly. In addition, engineering college network is now used on a daily basis. Various user departments have set up about 200 DRS.

The Karnataka State Government has decided to fund the total TDCC network for the state. The up-link has been established and the studio installation is in progress. The conversion of existing

DRS at 20 district locations to digital and installation of new DRS at 175 block locations are in progress. An engineering college network is also

being established.

In Orissa, training programmes are being conducted for 5 to 10 days a month using the Fly-Away Terminal (FAT) located at the Cuttack Studio. The DRS network includes all 30 districts and 80 blocks in (Koraput-Bolangir-Kalahandi) districts. The network is proposed to be upgraded using VSAT options to cater to various other services such as E-governance, NRIS, DMS, etc.

For the North Eastern Space Applications Centre (NE-SAC), several DRS have been installed and the training programme is expected to commence soon.

For the Andaman and Nicobar Islands 7 locations are proposed to be covered in the first phase. Priority will be given for interactive training programmes for field functionaries, educational institutes and schools.

For Goa, the uplink and studio have been established by the Goa University. The training of resource persons has been carried out. The DRS network covers 20 locations, which will be expanded to cover additional 80 locations.

The follow up action on a pilot proposal for Jhalwad and Baran districts in Rajasthan is being taken up. An assessment of available studio equipment and other facilities has been made.

New technologies are being used in TDCC network for multimedia lecture delivery and interactive distance learning. The network is being converted to digital mode to improve the capacity and quality of the system. It will also enable off-line downloading of lessons from servers at teaching end by the students.

7.7. TELEMEDICINE

Telemedicine is a recent application of the satellite communications that makes specialized medical facility available to the remote areas of the country. The expert consultancy could be obtained for the patients in remote areas from specialists in specialty hospitals in cities.

It may be as simple as two health professionals discussing a case over the telephone or as sophisticated as using satellite technology to broadcast a consultation between providers at facilities in two countries, using video conferencing equipment. It is used daily by most  health professionals and by military and some large medical centers .

        Two different kinds of technologies make up most of the Telemedicine applications in use today:

7.7.1. Store and forward

This is used for transferring digital images from one location to another. A  digital image is taken using a digital camera(‘stored’) and then sent (‘forwarded’)  to another location .This is typically  used for non emergent situations, when a diagnosis or consultation may be made in next 24 to 48 hours and sent back. The image may be transferred within a building, between two buildings in the same city, or from one location to another anywhere in the world.

Teleradiology :  The sending of x-rays, CT scans ,or MRIS is the most                       common application of telemedicine in use today .

Telepathology : Images of pathology slides may be sent from one location     to another for diagnostic consultation.

        Dermatology : It is also a store and forward technology. Digital images may be taken of skin conditions, and sent to dermatologist for diagnosis.

7.7.2.:   Interactive Television (IATV )

It is the technology used when a face to face consultation is necessary. It is usually between the patient and their provider in one location and a specialist in another location. Vedio conferencing equipments allow ‘real-time’ consultation to take place. Almost all specialist of medicine have been found to be conductive to this kind of consultation , including psychiatry  internal medicine, rehabilitation, cardiology , pediatrics and gynecology and neurology.

Five VSAT terminals have been set up for telemedicine in Chamarajanagar, Kenchanahalli, Bangalore, Kolkata and Tripura which are networked with a hub on shared basis. Port Blair in Andaman and Nicobar islands, and Leh in Jammu & Kashmir and Lakshadweep are also being provided with telemedicine facilities. ISRO has already provided its SPACENET terminals to a private hospital at Chennai and a rural Hospital at Argonda in Andhra Pradesh for telemedicine network. The Hospital at ISRO’s SHAR Centre, at Sriharikota is also being connected to this spacenet for telemedicine.

7.8. METEOROLOGY

The meteorological data provided by INSAT is processed and disseminated by the INSAT Meteorological Data Processing System (IMDPS) of India Meteorological Department (IMD). Upper winds, sea surface temperature and precipitation index data are regularly obtained. The 6 am GMT (Greenwich Mean Time), VHRR (Very High Resolution Radiometer) image-derived wind data are provided on Global Telecommunications System (GTS) of the World Meteorological Organization (WMO). The 3 am GMT full disc infrared pictures are transmitted as radio facsimile broadcast daily for reception in the neighboring countries.

INSAT-VHRR imageries are used by Doordarshan during news coverage and by newspapers as part of weather reporting. At present, repetitive and synoptic weather system observations over Indian Ocean from geostationary orbit are available only from INSAT system. The INSAT-VHRR data is available in near real-time at 32 Meteorological Data Dissemination Centres (MDDC) in various parts of the country. With the commissioning of direct satellite service for processed VHRR data, MDDC type of data can now be provided at any location in the country.

One hundred meteorological Data Collection Platforms (DCPs) have been installed all over the country and also at Schiramacher, the Indian base station in Antarctica. The DCP services are provided using the Data Relay Transponders of INSAT-2B. Central Water Commission (CWC) and Snow and Avalanche Study Establishment (SASE) are using INSAT for real-time hydro-meteorological data collection in the Mahanadi and Chambal basins. Narmada Control Authority (NCA) is also planning to use the INSAT DRT data.

About 250 Cyclone Warning Dissemination System (CWDS) receivers have been installed in the cyclone-prone coastal areas of Andhra Pradesh, north Tamil Nadu, Orissa, West Bengal and Gujarat, with DWS uplink from Chennai, Mumbai and Kolkata. The receivers are selectively addressable.

A cooperative agreement has also been signed with the European meteorological satellite, EUMETSAT, for using data from METEOSAT-5 satellite, which is located at 63 degree east longitude in exchange for weather pictures of India’s INSAT.

7.9. SATELLITE AIDED SEARCH AND RESCUE (SAS&R)

As a member of the international COSPAS-SARSAT programme for providing distress alert and position location service through LEOSAR (Low Earth Orbit Search And Rescue) satellite system, India has established two Local User Terminals (LUTs) one at Lucknow and the other at Bangalore.

In addition, INSAT-2B is equipped with 406 MHz Search and Rescue payload, which picks up and relays alert signals originating from the distress beacons of maritime, aviation and land users. Based on the performance demonstrations of INSAT, the system has now been adopted as an integral part of the international COSPAS-SARSAT system for satellite-aided search and rescue operations complementing the LEOSAR system.

Indian LUTs provide coverage to a large part of Indian Ocean providing distress alert services to Bangladesh, Bhutan, Kenya, Maldives, Nepal, Seychelles, Somalia, Sri Lanka and Tanzania. The operations of INMCC/LUT are funded by the participating agencies, namely, Coast Guard, Airports Authority of India (AAI) and Director General of Shipping and Services.

INSAT-GEOSAR Local User Terminal (GEO LUT), located at Bangalore, is integrated with INMCC. The distress alert messages originating from the Indian service area are detected at INMCC which are passed on to Indian Coast Guard and Rescue Coordination Centres (RCCs) at Mumbai, Kolkata, Delhi and Chennai. Coast Guard, Navy and Air Force carry out the search and rescue activities. The INMCC is linked to the RCCs and other international MCCs through automatic telex and Aeronautical Fixed Telecommunication Network (AFTN). The Indian LUTs and MCC provide service round the clock and maintains the data base of all 406 MHz registered beacons equipped on Indian ships and aircraft.

7.10. VSATS

VSATS stands for very  small aperture terminal system .

This is the distinguishing feature of a VSAT system, the earth station antennas being typically less than 2.4 m in diameter . The  trend  is toward even smaller dishes , not more than 1.5 in diameter. VSAT includes private networks , mostly providing two way communication facilities. Typical user group includes banking and financial institutions, airline and hotel  booking agencies, and large retail stores with geographically dispersed outlets.

The basic structure of VSAT network consists of a hub station which provides a broadcast facility to all the VSATs in the network , and  the VSATs themselves which access the satellite in some form of multiple-access of mode .The hub station is operated by the service provider , and it may be shared among a number of users , but off course each user organization has exclusive access to its own VSAT network .Time division multiplex is the normal down link  mode of transmission from hub to the VSATs in a network , or addressing coding can be used to direct messages to selected VSATs.

Most VSATS systems operate in Ku band, although there are some C-band systems in existence.

The major shortcomings of the present day VSAT system are the high initial costs, the tendency towards optimizing systems for the large networks and lack of direct VSAT – to-VSAT links. Technological improvements, especially in the area of microwave technology and digital signal processing will result in VSAT systems in which most if not all of these shortcomings will be overcome.