The main ground station for receiving Pratham signals is situated on the roof-top of Aerospace Department of IIT Bombay. It has the following major functions:
- Satellite tracking and receiving segment
- Uplink transmission segment
- Payload data logging
Main Ground Station of Pratham on the roof-top of Aerospace Department, IIT Bombay
Ground Station Block Diagram
At the GS we have some self-fabricated and some off-the shelf components.
- Antennas: Two pairs of crossed yagi antennas, one pair for each frequency band i.e. central frequency 145.98 MHz, 437.455 MHz
- Transceiver base station: Kenwood TS2000 radio demodulates the FSK signal and stores the data in the mainframe.
- A pair of AD8302 modules measures RF gain and phase value between the two inputs it takes Uses Log amplifiers to calculate the value of log (InpA/ InpB)
- Low Noise Amplifiers: 4 low noise amps are being used on the distinct feeds from antennas
- Rotor arrangement with an Interface circuit to integrate the device with software architecture. Rotor (Yeasu G-5500) is being used to orient the antenna structure to the required inclination with respect to reference level. The rotor interacts with the mainframe via Rotor Controller Interface (RCI-USB by EA4TX)
Ground Station Mainframe Setup