उपग्रह संचार अनुप्रयोग

One most important mandate of North Eastern Space Applications Centre (NESAC) is applications of Satellite Communication (SATCOM) technology to undertake developmental communication programmes in the North Eastern Region (NER) to assist education, health, social welfare and other development activities. The SATCOM application programs can addresses the dissemination of quality education- from primary to University level, provisioning of Medical and Health-care services, enabling of interactive connectivity among the rural farming communities , tele-communication support during disaster management etc. To cater this all this ISRO has a number of vibrant SATCOM applications programs like Telemedicine, Te-education, Village Resource Centre, Communication support in disaster management etc. NESAC is playing the key role in implementation & utilization of all above applications programs in all the eight state of NER in collaboration with other central/state government agencies, NGO’s etc.

The available SATCOM facilities at NESAC are as follows:

  • State-of-the art studio facility for content generation and broadcasting of developmental programs.
  • ISRONET system for video conferencing and data transfer activities among the centre of DOS/ISRO.
  • Transportable WLL-VSAT system for providing audio-video link and data transfer activities for communication support in Disaster management and various training and awareness program.
  • MHA-VPN node for communication support in Disaster management.
  • Type D Terminal for communication support in Disaster management.
  • Spectroradiometer.
  • Mobile apps for field data transmission during disaster as well under projects for ground truth.
  • Various system under Ka-band propagation experiment program.
  • IRNSS project (ISTRAC/ISRO navigational program).

The Ongoing SATCOM applications programs are as follows


Telemedicine today is one of the most vital SATCOM application programmes of ISRO. The Telemedicine Programme is an innovative process of synergising benefits of Satellite communication and information technology with Biomedical Engineering and Medical Sciences to deliver the health care services to the remote, distant and underserved regions of the country. ISRO has made a modest beginning in telemedicine using satellite communication in the form of a telemedicine pilot project in the year of 2001, connecting Apollo Hospital at Chennai with the Apollo rural hospital at Arogonda village in the Chittor district of Andhra Pradesh. Now a number of telemedicine networks are operational all over the country.

For north eastern states a project known as ISRO-NEC telemedicine project has been formulated in July 2004 using satellite communication through Very Small Aperture Terminal (VSAT) to commission 72 telemedicine nodes in all the districts of all the north eastern states including Sikkim. The state wise breakup of the nos. of telemedicine centre is: Arunachal Pradesh-8, Assam-23, Manipur-9, Mizoram-7, Meghalaya-9, Nagaland-8, Sikkim-4 and Tripura-4.The major objectives of the project is to connect the district level hospitals to the specialty/super specialty hospitals of the region as well as outside the region for better healthcare at minimum cost using modern technology. The major stakeholders of the project are ISRO, North Eastern Council (NEC) and state governments of the region. NESAC is coordinating the project from ISRO side in installation & commissioning of the system, training, monitoring, trouble-shooting etc. Till date a total of 25 telemedicine centres (Table 1) has been commissioned and remaining 47 are in pipeline. Another telemedicine project known as Army Telemedicine Network for NER is also operational in the north eastern states in collaboration with Indian Army form March 2008. Under this network a total of 6 telemedicine centre (Table 2) has been commissioned in various army hospitals in the region.

List of civilian Telemedicine centre in NER under ISRO-NEC joint Telemedicine program

State Total nos. of Telemedicine centre commissioned under ISRO-NEC joint Telemedicine project Location
Arunachal Pradesh 4 (Four)

1. Ram Krishna Mission Hospital, Itanagar.

2. General Hospital, Naharlagun.

3. Civil hospital, Passighat

4. Civil Hospital, Tawang

Assam 7 (Seven)

1. Guwahati Medical College & Hospital, Guwahati

2. Assam Medical College & Hospital, Dibrugarh

3. Jorhat Medical College & Hospital, Jorhat

4. Civil Hospital, Tinsukia

5. Civil Hospital, North Lakhimpur

6. Civil Hospital, Golaghat

7. Civil Hospital, Hailakandi

Manipur 1 (One) 1. Regional Institute of Medical Science (RIMS), Imphal
Meghalaya 4 (Four)

1. North Eastern Indira Gandhi regional Institute of Health & Medical Science (NEIGRIHMS), Shillong

2. Civil Hospital, Shillong

3. Civil Hospital, Jowai

4. Civil Hospital, Tura

Mizoram 4 (Four) 1. Civil Hospital, Aizawl 2. Civil Hospital,  Lunglei 3. District Hospital,  Saiha 4. Civil Hospital,  Champhai
Nagaland 1 (One) 1. Civil Hospital, Mokukchang 
Sikkim 1 (One) 2. S.T.N.M Goverment Hospital, Gangtok
Tripura 3 (Three)

1. Sub- Divisional Hospital Dharmanagar.

2. Civil hospital, kailsahar

3. Sub-Divisional Hospital, kamalpur.

List of civilian Telemedicine centre in NER under ISRO-NEC joint Telemedicine program

 State Total nos. of Telemedicine centre commissioned under Indian Army Telemedicine project Location
Assam 2 (One)

1. 151 Base Hospital, Basistha , Guwahati

2. Military Hospital, Silchar

Manipur 1 (One) 1. Military Hospital, Liemakhong
Meghalaya 1 (One) 1. Military Hospital, Shillong
Nagaland 1 (One) 1. Military Hospital, Dimapur
Tripura 1 (One) 1.Military Hospital, Agartala


Beside this 31 (25 + 6) telemedicine centres, there are a number of telemedicine centre in NER commissioned by ISRO under different network. The locations of these centres are:

  • Dr. B Barooah Cancer Institute, Guwahati, Assam.

  • Srisankardeva Nethrayalaya, Guwahati, Assam.

  • Tripura sundari District Hospital, Udayapur, Tripura

  • Govt. Cancer Hospital, Agartala

  • Civil Hospital, Kohima etc

These telemedicine centres are providing noble services to the people of NER in health sector. Thousands of tele-consultancy and Continuing Medical Program (CME) has been carried out connecting many specialty and super-speciality hospitals like All India Institute of Medical Science, New Delhi; Narayana Hrudalaya, Bangalore; Amritha Institute of Medical Science, Cochin; Sri Ramchandra Medical College & Hospital, Chennai; Sanjay Gandhi Post Graduate Institute of Medical Science, Lucknow; Tata Memorial Centre, Mumbai; Fortis Hospital, Noida etc. A large nos. of patients as well as doctors are benefitted by this health service.

One important aspect of SATCOM applications in the North Eastern States is the Tele-Education Project. This project was envisioned in a manner as to create state-wise SATCOM networks for the eight North Eastern states disseminating quality education programmes for different levels of the academia. Based on the hub networking topology, the NER EDUSAT network has its hub suitably placed somewhere in the state capital with the remote ends (SITs) housed in some identified primary and higher secondary level schools, colleges. The hub has one Studio facility from where content is to be generated by experts and then broadcasted to the targeted recipients.

Terrestrial hubs are used to link to and from terminals and convey services like virtual classroom. The standard used is called Digital Video Broadcasting, Return Channel via satellite (DVB-RCS). The DVB-RCS is a system that allows two-way communication between the Satellite Interactive Terminals (SITs) installed at customer's sites via the hub. The DVB-RCS system operates as a Star configuration, thus its central station is called the "Hub." This station implements the forward link via a conventional DVB-S chain (similar to digital TV broadcasting) while the return link is implemented using the DVB-RCS standard. The Hub consists of microwave equipment for the transmission and reception of signals and a control centre for managing network traffic. This station also hosts interfacing equipment supporting a wide range of terrestrial interfaces. An important Hub function is to map the traffic of all remote terminals belonging to each user group.

Also called as the Expert Node, the Teaching End is the place where the contents (subject/topic wise) are created by experts and delivered in a time-scheduled manner using preinstalled third-party software. A general configuration of the teaching end


The student end consists of the Receive-only Terminals (ROTs) and the Satellite Interactive terminals (SITs) also called the Return Channel Satellite Terminals (RCSTs). Students/ targeted user group can receive the contents transmitted and even interact with the experts at the teaching end directly (facility available in SITs only) using a preinstalled third-party software.


Status of EDUSAT Network in the NER

Already commissioned

HUB & Studio at SIRD extension centre, Kahikuchi, Guwahati and 32 SITs at SIRD extension centres and DIETs across the state. The network is already operational.

HUB & Studio at DERT, Shillong & 52 SITs at various schools and educational institutes across the state. The network is already operational.

1 Hub & Studio at Rajib Gandhi University, Itanagar & 52 Satellite Interactive Terminals (SITs) at various schools and educational institutes across the state. The network is already operational.

HUB & Studio at SCERT, Agartala & 50 SITs at various schools and educational institutes across the state. The network is already operational.

HUB & Studio at Kohima Science College, Kohima & 44 SITs at various schools and educational institutes across the state. The network is going to be made operational soon.

HUB & Studio at SCERT, Aizawl & 46 SITs at various schools and educational institutes across the state. The network is going to be made operational soon.

HUB & Studio at SIRD extension centre, Kahikuchi, Guwahati and 49 SITs at SIRD extension centres and DIETs across the state. The network is already operational.

1 HUB & Studio & 50 SITs across the state

Already Commissioned

ISRO has initiated the setting up of the VRC with a view to integrate its capabilities in satellite communications and satellite based earth observations to disseminate a variety of services emanating from the space systems and other IT tools to address the changing and critical needs of the rural community. This project strives to promote a need based single window delivery system for providing services in the areas of education, health, nutrition, weather, environment, agriculture and livelihoods to the rural population and to empower them to face the challenges. The VRC is a totally interactive VSAT (Very Small Aperture Terminal) based network. VRCs will be set up in association with grass root level organisations, who have a strong field presence and experience of mobilising communities to act for development and proven track record.

In NER states 40 VRC has been commissioned till now (Assam-13, Nagaland: 8, Sikkim: 19 and Meghalaya: 1). At present these are under revival.

The Indian Regional Navigation Satellite System (IRNSS) program of ISRO is the first Indian initiative toward an independent, indigenously built Regional Satellite Navigation (SATNAV) Project. The IRNSS is based on a constellation of seven satellites, three in GEO (Geostationary orbits) and four in GSO (Geosynchronous orbits). NESAC has been identified as one of the four sites for commissioning one set of IRNSS Ground segment element. NESAC is having IRNSS CDMA Ranging Station (IRCDR), IRNSS Range and Integrity Monitoring Station (IRIMS) and IRNSS Data Communication Network (IRDCN) system under the project.

Content to be updated....

A state of the art studio facility is available at NESAC The purpose of the studio is content generation on various subject matter like education, health, disaster management etc. focusing on societal development in NER using space technology.

Ka-band propagation experiment is a national level study administered by Space Applications Centre (SAC), Ahmedabad and NESAC is one of its participatory agency. ISRO is planning to utilize Ka- band radio frequency for communication purpose in India. But Ka- band radio frequency is more susceptible to high signal attenuation during rain and cloudy weather, which will seriously degrade the services. To study the effects of these meteorological parameters on Ka Band radio propagation this experiment has been planned by SAC, Ahmedabad. Under this project, a number on equipment like Disdrometer, Microrain Radar (MRR), Rain Gauge, Datalogger etc has been already commissioned and functional. Meteorological data archival and analysis is going. A Dual frequency Beacon Transmitter (20.2 and 30. 5 GHz), Radiometer etc will be installed very soon. A special cabin has been constructed for housing the equipments under the project.