This internship is in german
Lab Course Weather Satellite
This laboratory is only accessible for Bachelor students from the electronic engineering faculty of the university of Stuttgart.
The Institute of Signal Processing and System Theory will be offering an interesting and challenging lab course. The course has been designed as a practical course, for which students, in teams of two, can choose freely from the following topics:
- Design and implementation of a receiving system for weather satellites (demodulation, synchronization, composition of the weather image, pseudo-color imaging)
- Localization of a weather satellite receiver (estimation of the doppler frequency, estimation of the satellites' or the receiving system's Position, charting the position in a map)
Students will be expected to work independently on their chosen topic. The lab rooms will be accessible during normal working hours (during the day). Attendance is only required during four afternoons, which can be chosen freely. At the end of the semester each group will have to give a short presentation about the results of their work and elaborate on it in a short paper.
A detailed list of scheduled lab dates and the registration can be found in ILIAS.
This semester, the lab course will be offered in both German and English (each team will be able to choose individually between the two languages).
The order in which students sign up for the class is not important. In case the number of people enrolling should exceed the maximum number of available spots (14 students), participants will be chosen by lot from both bachelor (diplom) and INFOTECH students.
NOAA - Satellites
Since 1960, the American National Oceanic and Atmospheric Administration (NOAA) has been operating satellites in order to monitor weather and climate. The satellites follow an orbit close to Earth, which leads them over both the South and the North Pole.
The NOAA-satellites have four main functions, which consist of
monitoring the Earth, including its climate and the environment
measuring the proton and electron flux at their altitude
ollecting and forwarding the measured data of measuring stations that are located at a great distance or have been distributed far apart such as measuring buoys or weather balloons
the satellite-based location and tracing of emergency signals (SARSAT) by e.g. ships
Two of the AVHRR camera's spectral bands, selected by the NOAA ground control station, are broadcast in a reduced resolution on a VHF-frequency between 137 MHz and 138 MHz with the Automatic Picture Transmission system.
APT - Automatic Picture Transmission
Via a VHF connection, the Automatic Picture Transmission (APT) sends two of the six AVHRR channels to Earth. To receive the APT signal no license or authorization by NOAA is required. The following illustration shows a simplified block diagram of the NOAA satellite's sending system.
The recorded scanning lines are continuously processed and broadcast by the APT-sending system. As soon as a NOAA satellite rises above the horizon of a certain receiving antenna and radio contact exists between the antenna and the satellite, the first scanning line can be received. This line depicts the part of the Earth which at this point in time is located vertically below the satellite. During the overflight, scanning line after scanning line is received until the satellite sets on the other horizon and the radio connection breaks off again. The result of this is the last representable scanning line. The following illustration represents the spectra of the received (and partially preprocessed) signals. These signals form the basis for the lab course. They will be available as WAV files, and, during the run of the lab course, students are expected to process them digitally (in order to e.g. obtain the weather satellite's image.)
Excerpts from a received signal can be heard here:
Received weather image, rendered in pseudo-color (click image for large view, 3.0 MB)