SDR Helix Antenna Deployment Experiment (SHADE) on board BEXUS

Abstract

In the field of space travel, space communications has always presented a slew of obstacles and hurdles that must be overcome in order to complete a successful mission. Space limits inside a satellite or spaceship, vast distances between satellites and ground stations, and a phenomenon known as "Faraday Rotation" in the ionosphere are only a few of the most typical issues. Satellite antennas must be small, compact, efficient, and circularly polarized as a result of the aforementioned issues. The helix antenna is an excellent answer for all of the requirements. In this work we develop a deployment and pointing mechanism of a helix antenna operated with software defined radio algorithms. The features of helix antennas are exceptional, and they are especially suitable for satellite communication. Three coaxial cylinders, two stepper motors, one pulley, and one thread make up a deployment-pointing mechanism. The mechanism deploys the antenna along its longitudinal axis and turns it horizontally towards the ground station. During the flight, the antenna is deployed and retracted. Under different positioning situations, the GPS, an altimeter, and a compass calculate the gondola's position in order to rotate the antenna towards the Ground Station and close the communication link. The antenna's rotation mechanism is triggered by the integrated attitude determination and control system algorithms in order to correct the pointing and orientation towards the Ground Station. The antenna uses software defined radio algorithms to achieve weight and volume reductions while maintaining high efficiency and reconfigurability. The experiment includes a high-definition camera that provides real-time information on the antenna's orientation and condition. SHADE's flight on the BEXUS 28/29 balloon resulted in effective deployment and transmission, as well as the ability to receive and decode transmitted packets. The rotating mechanism met the pointing requirements, and all of the sensor's data was correctly saved to our system. Throughout the trip, there were no signs of thermal risk