Active Sun- Tracking System for Laser Heterodyne Spectro- Radiometer

Abstract

Ground- based laser heterodyne systems can be used to measure the concentration of gases in the atmosphere. These measurements are of increasing importance due to Earth's changing climate. To take these measurements most accurately, the light used in the system should come from the Sun. An active sun- tracking system is designed for this purpose, which can rely on both moving to the sun's calculated position dependent of actually observing the sun, and actively tracking the sun using a camera. The techniques implemented when designing the sun- tracking system are similar to those used when designing sun- tracking solar panels. The entire system was designed on a breadboard, with components to both track the sun and observe the light for radio- spectroscopy. The active sun tracking system proved successful, and upon observation of the sun the method for calculating the gimbal's position based on the sun's calculated position is revised. Light exiting from the telescope is successfully coupled with the detector, and the light is also mixed with 1650nm laser. However, light from the sun was not available for viewing when this part of the system was complete, and the observed signal was very faint.