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.