Beacon

Beacon is the satellite’s signal that signifies its presence to the world and can be tracked by almost any Ground Station or amateur radio operator. Generally, the signal in beacon primarily has the call sign of the satellite and may also have health data or telemetry data. This signal is generally transmitted in Morse code, following the International standard format which is achieved by OOK (On-Off keying) technique. The implementation of the OOK modulation can be done by many ways, like using dedicated ICs, or by using a microcontroller. The factors to be looked into while designing the system for beacon in satellite are:

• Power Amplification of Signal
• Longevity (life) of components
• RF designing
• Antenna matching for the beacon frequency
• Interface with other boards and components as per System Requirement

Case Study - Pratham

Beacon flow diagram

In Pratham, a specific Beacon board was designed. The signal of frequency 145.980 MHz, was generated using the Quartz crystal. The signal frequency is allotted by International Amateaur Radio Union (IARU). The implementation of the OOK modulation for the Morse code is achieved by toggling the Power Amplifier ON and OFF. The data transmitted from beacon had the following information:

1. Call Sign: VU2BUG
2. Identification and data: IIT Bombay Student Satellite, Pratham

The beacon signal was successfully received from our own Ground Station and many Ground Stations across the world. Here's some more details about tracking Pratham.

Pratham's beacon signal received in Brazil. You can see the decoded Morse code.

---

If you are done reading this page, you can go back to Communications Subsystem.