Building a Low-Cost Ground Station for Weather Satellite Image Reception

Abstract

In this Thesis, a small, low-cost, portable and easily deployable ground station was built, to track and receive signals from National Oceanic and Atmospheric Administration (NOAA) weather satellites (series 15, 18 and 19) in VHF and UHF bands, process and convert these to images are presented. A ground station, capable of receiving reasonably good quality images from NOAA weather satellites was built. The Tunstile antenna of the ground station was built using parts of an old TV antenna found on the rooftop of an apartment building. The remaining part of the ground station was built using lost-cost materials such as an RTL-SDR dongle an analog front-end software defined radio with a USB interface to computer, Low Noise Amplifier (LNA) with 23 dB gain, screws, cables and jumpers totaling less than NOK 400, supported by MATLAB and open source software. Different software are used to activate the ground station, open source software such as WXtrack and Orbitron were used to track and predict the orbit, timing and movement of the satellite. These software can track and predict a wide range of satellites. In this Thesis, the main focus has been on tracking NOAA weather satellites. WXtoImg was used to decode and convert signals received through virtual cabling (audio piping) in real-time from SDR# into grey scale images and uses fake colors (random colors were assigned to different features) to distinguish between geological and geographical features, including borders between nations as these are imbedded within the software. While MATLAB was used to conduct signal spectrum analysis and decoding of previously saved audio signals from SDR# to images. The chosen combination of software and hardware components made the ground station capable of tracking satellites with different power levels, as well as different modulation and error-correction schemes. The architecture of the antenna, and the performance evaluation and analysis of the ground station were completed after repeated attempts and experiments resulting in a vast number of images. During the Thesis, new functions of the Ground Station were discovered. By using MATLAB and other open source software, the Ground Station was capable of II exploring local FM radio stations, DAB radio signals, DVB-T TV signals, GPS signals, as well as detecting aircrafts and drones overhead. Making a Ground Station for satellite images reception from waste and low-cost materials available in most local markets, will be particularly important for researchers, students and practitioners in income-poor and conflict countries where they have few resources and limited access to modern technology.