GSAT-7B satellite

In news– The Defence Acquisition Council (DAC) headed by the Defence Minister has given the Acceptance of Necessity (AoN) for procurement of a GSAT 7B satellite recently.

About GSAT 7B satellite–

It is the state of the art, multi-band, military-grade satellite that will primarily fulfill the communication needs of the Army.
Currently, the Army is using 30 percent of the communication capabilities of the GSAT 7A satellite, which has been designed for the Indian Air Force (IAF).
It will also help the Army enhance its surveillance in border areas.

Other GSAT series satellites-

GSAT 7 satellite:

GSAT 7 satellites are advanced satellites developed by the ISRO to meet the communication needs of the defence services.
It was launched in August 2013 from an Ariane 5 ECA rocket from Kourou in French Guiana.
It is a 2,650 kg satellite which has a footprint of nearly 2,000 nautical miles in the Indian Ocean region.
This satellite is mainly used by the Indian Navy for its communication needs.
It provides a gamut of services for military communication needs, which includes low bit voice rate to high bit rate data facilities, including multi-band communications.
Named Rukmini, the satellite carries payloads in UHF, C-band and Ku-band, and helps the Navy to have a secure, real time communication link between its land establishments, surface ships, submarines and aircraft.
The satellite was injected into a geosynchronous transfer orbit (GTO).

GSAT 7A (Indian Angry Bird):

The GSAT 7A was launched in 2018 from the Satish Dhawan Space Centre in Sriharikota, and has gone a long way in boosting the connectivity between the ground radar stations, airbases and the airborne early warning and control aircraft (AEW&C) of the IAF.
It also helps in satellite controlled operations of unmanned aerial vehicles (UAVs) which gives a great deal of reliability to the operations as compared to ground controlled operations.
This satellite has 10 channels in Ku band with switchable frequency for mobile users, one fixed Gregorian or parabolic antenna, and four steerable antennae.

GSAT 7C satellite:

It is on the cards for the IAF, and a proposal to this effect was cleared by the DAC in 2021.
This satellite would facilitate real time communication with IAF’s software defined radio communication sets.
It will increase the capability of the IAF to communicate beyond the line of sight in a secure mode.

Other kinds of military satellites of India-

An Electromagnetic Intelligence Gathering Satellite (EMISAT)-

EMISAT was developed by ISRO, and was launched in April 2020 through a Polar Satellite Launch Vehicle (PSLV-C45).
It has an Electronic Intelligence (ELINT) package called Kautilya, which allows the interception of ground-based radar and also carries out electronic surveillance across India.
The ELINT package provides the capability in direction-finding of radar and fixing their locations.
It is placed in a 748-km orbit, and is said to be based on the Israeli satellite system.
This satellite circles the globe pole-to-pole, and is helpful in gathering information from radars of countries that have borders with India.

RISAT 2BR1 synthetic aperture radar imaging satellite-