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POLNET COMMUNICATION

This is a combination of Satellite Communication and UHF Communication. Single Satellite in Geo-stationary orbit work as an active repeater which covers the entire country.

The VSATs (Very Small Aperture Terminal) are used for Satellite Communication. MART (Multi-Access Radio Telephony) System is used for UHF Communication. 

VOICE / DATA / FAX can work simultaneously by multiple users in the VSAT Stations while MART is specially used for VOICE Communication from Police Station to Police Station and District Station. The range is limited by 35 Kms Line of Sight and repeater Stations will be used when required. 

The network can function in two Systems:- 

(1)   Combination of MESH & STAR Topology in State Head Quarters.

(2)   STAR Topology for District Head Quarters. 

In MESH System, any Earth Station can communicate with each other through the Satellite Transponder directly. This system is provided in the State Head Quarters. In this System, a dish antenna is required. The diameter of the dish is 3.8 Metres. 

In the STAR System, the Earth Stations can not communicate with each other directly through the Satellite Transponder. In this system, HUB is required. In POLNET, HUB has been proposed at Delhi. This is an Earth Station with large dish antenna of 11 Metres diameter and powerful transmitter up to 2 KW.The signal from one Base Station for another Base Station is transmitted to the Satellite which sends signal to the HUB where it is boosted, routed by Network Management System and is retransmitted to the Transponder Satellite, which in turn sends the signal to the desired Base Station. 

At present, total 833 VSAT Stations have been included under this scheme. The capacity of the HUB is 1500.

MCS-VSAT This software is used for point-to-point text messaging up to 40 KB at a time using X.3 Parameters.

FTP File Transfer Protocol is used for exchanging all types of files / folders.   

Webmail It is a Mail / Information exchange System among all States / District Head Quarters using an IMAP (Internet Message Access Protocol) Server based on Linux platform through the allotted mailboxes located at POLNET HUB at New Delhi.            

This is a combination of Satellite Communication and UHF Communication. Single Satellite in Geo-stationery orbit work as an active repeater which covers the entire country. 

The V-SATs (Very Small Aperture Terminal) are used for satellite Communication . Multi-Access Radio Telephony system is used for UHF Communication. 

VOICE / DATA / FAX can work simultaneously by multiple users in the VSAT stations while MART is specially used for VOICE Communication from Police Station to Sub-Divisional Station and District Station. The range is limited by tower height and repeater stations will be used when required

The network can function in two systems 

   (1) MESH System   In State Headquarters  (2) STAR System   for District Headquarters      

In MESH system any earth station can communicate with each other through the Satellite Transponder directly. This system is used in the State Headquarters. In this system a dish antenna are required.The diameter of the dish is 4 meters. 

In the Star system the base stations cannot  communicate with each other directly  through the Satellite Transponder. In this system Hub is required. In POLNET, Hub has been proposed at Delhi.

This is a base Station with large dish antenna of about 16 meters diameter and powerful transmitter.

The signal from one base station for another base station is  transmitted to  the satellite which sends signal to the Hub where it is boosted and is retransmitted to the transponder satellite, which in turn sends the signal to The desired base station. 

At present total 833 V-SAT Stations have been included under this scheme. The capacity of the HUB is 1500. 

 

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