Disasters have become multination and often spread in very wide geographical areas. To conduct any disaster management activity correct navigation is must. Navigational satellites are proving boon for this purpose. One can reach to disaster victims very quickly by locating their position in real time. It also helps in coordination between teams and instruments. For any successful operation of search and rescue three things are must. These are  localisation, navigation and timing .Navigation satellites provide  these three main datasets : localisation, timing and  navigation. Coordinates for real time navigation are obtained  in three dimensional form through satellites data. Navigation speeds up the process of reaching the disaster area and locating the victims. It makes the search and rescue work safer, faster, and easier. High accuracy of satellite timing system helps in better  synchronisation of  search and rescue equipment and tools running on electronics. It also increases the reliability and sustenance of the system. Various software of disaster management use Navigation satellites. IRNSS,GNSS(global navigation satellite system), GPS(global positioning systems), GLONASS( Global Navigation Satellite System) and Galileo are  various navigational systems being used in emergency management, rescue operations, time information, localisation and various other fields. IRNSS is an independent regional navigation satellite system being developed by India. It is designed to provide accurate position information service to users in India as well as the region extending up to 1500 km from its boundary, which is its primary service area. An Extended Service Area lies between primary service area and area enclosed by the rectangle from Latitude 30 deg South to 50 deg North, Longitude 30 deg East to 130 deg East. IRNSS will provide two types of services, namely, Standard Positioning Service (SPS) which is provided to all the users and Restricted Service (RS), which is an encrypted service provided only to the authorised users. The IRNSS System is expected to provide a position accuracy of better than 20 m in the primary service area. Some applications of IRNSS are:

Applications of IRNSS

• Terrestrial, Aerial and Marine Navigation
• Disaster Management
• Vehicle tracking and fleet management
• Integration with mobile phones
• Precise Timing
• Mapping and Geodetic data capture
• Terrestrial navigation aid for hikers and travelers
• Visual and voice navigation for drivers

The IRNSS Signal-in-Space Interface Control Document (ICD Ver. 1.1) for Standard Positioning Service (SPS) is released to the public to provide the essential information on the IRNSS signal-in-space, to facilitate research & development and aid the commercial use of the IRNSS signals for navigation-based applications. IRNSS-1A spacecraft provides messaging service to users in the Indian region. The Signal-in-Space Interface Control Document (ICD Ver. 1.0) for Messaging services (IRNSS 1A) is released to the public to provide the essential information to facilitate the use of IRNSS1A Signal-in-space for development of receiver. Download Signal-in-Space Interface Control Document (ICD Ver. 1.0) for Messaging services (IRNSS 1A)

IRNSS-1A is the first satellite in the Indian Regional Navigation Satellite System (IRNSS). It is one of the seven satellites constituting the IRNSS space segment. Payloads - IRNSS-1A carries two types of payloads navigation payload and ranging payload. The navigation payload of IRNSS-1A transmits navigation service signals to the users. This payload is operating in L5-band and S-band. A highly accurate Rubidium atomic clock is part of the navigation payload of the satellite. The ranging payload of IRNSS-1A consists of a C-band transponder which facilitates accurate determination of the range of the satellite. IRNSS-1A also carries Corner Cube Retro Reflectors for laser ranging.

1425 kg
Physical Dimensions	1.58 metre x 1.50 metre x 1.50 metre
Orbit	Geosynchronous, at 55 deg East longitude with 29 deg inclination
Power	Two solar panels generating 1660 W, one lithium-ion battery of 90 Ampere-Hour capacity
Propulsion	440 Newton Liquid Apogee Motor, twelve 22 Newton Thrusters
Control System	Zero momentum system, orientation input from Sun & star Sensors and Gyroscopes; Reaction Wheels, Magnetic Torquers and 22 Newton thrusters as actuators
Mission Life	10 years
Launch date	Jul 01, 2013
Launch site	SDSC SHAR Centre, Sriharikota, India
Launch vehicle	PSLV - C22

The space segment consists of the IRNSS constellation of eight satellites, NavIC. Three satellites are located in suitable orbital slots in the geostationary orbit and the remaining four are located in geosynchronous orbits with the required inclination and equatorial crossings in two different planes. All the satellites of the constellation are configured identically. The satellites are configured with I-1K Bus to be compatible for launch on-board PSLV.