JANUS : General Telemetry Test Transmitter
Robert Rönnholm · Diva portal (Dalarna University Library) · 2007
The purpose of this thesis was to develop a device that transmits telemetry data. The request for such a device was made by RFN – a government aeronautic test range located near Vidsel, Sweden. The data sent out from the device will consist of a simulation of a customer’s test flight transmission. One of RFN’s demands was that the PCM bit rate of the device would reach 20 Mbit/s. This prohibited the mere use of a PC. Instead, an electronic front- end was designed and integrated with a PC104, which would contain a web based user interface as well as serve as real-time sensor reader. These real- time sensors included a GPS receiver and a flight termination system. Another demand was that the system would be tough enough to be carried under a helicopter or towed by a plane, all seasons of the year. Considering this, the PC104 all electronics had to be rugged and temperature resistant. The design of the front-end proved to be a challenging task. The sought for wide tuning possibilities of the finished product called for an advanced schematic, with 4 different RAM groups and more than 40 other IC’s. With the current prototype it is possible to set the output bit rate, the data alignment and the number of bits per word, together with other traits of the transmitted data matrix. After the development time and a revision of the project goals, this project was a success.