An overview of the secondary payload mission
We’re working with a company called QEYnet to target a laser beacon at Earth.
Encryption is how we secure information over the internet, and the way it works is with very complex math equations. However, problems arise with Quantum computers - they can break current encryption methods very easily. QEYnet, the company responsible for the secondary payload beacon, is trying to solve this issue by distributing Quantum encryption keys through satellites via laser uplinks and downlinks.
QEYnet is testing their tracking IR downlink - essentially an infrared laser that lets them know if they’ve locked on to the right target. By mounting their laser beacon on our satellite, they’ll be able to test its functionality and move forward with their prototype.
We’re treating the laser beacon as more or less a black box - we supply it with power, and turn it on when we get a message to turn it on. Things get more complex when it comes to pointing it in the right direction - the entire secondary payload mission will be during eclipse, when Earth is between the satellite and the Sun. During eclipse, we can’t use our sun sensors to orient ourselves, but we need 0.1 degrees of pointing accuracy from the satellite to run the mission.
The way we maintain the pointing accuracy required is to shoot a laser at the satellite from the ground (hereafter referred to as the ground beacon). This will then be detected by a secondary payload camera, which will use the laser’s position in the photo and knowledge of the latitude and longitude of the ground beacon to determine the orientation of the spacecraft.
We’re selecting the laser parameters for the laser beacon, (wavelength, power, and angle of dispersion), as well as a secondary payload camera, lens, and optical filters to reduce noise in the laser detection process. In addition, we need to develop an algorithm to translate the image data into commands for ADCS to process, as well as have the basic firmware and subroutines for taking images at the right frequency to get enough optical data without overloading our processor.