In English

Active electronically controlled IFF-antenna for L-band

Albin Nilsson ; David Schultze
Göteborg : Chalmers tekniska högskola, 2018. 96 s.
[Examensarbete på avancerad nivå]

The projects purpose is to design, build and measure a transmitter and receiver module (TRM) and antenna prototype for an IFF/SSR system using Active Electronically Scanned Array (AESA) technique, which is unique in these systems. The project concludes the design, build and measurement of a TRM split in its basic blocks in the form of test circuits. An antenna array with 10+4 active elements are designed, build and measured in an anechoic chamber. The project successfully resulted in a theoretical power to each element of 953W at 1dB compression. The 2nd and 3rd harmonic generated from the system could be kept within the IFF standard limit with the manufactured filter in this project. The antenna constructed using dipoles has an active reflection factor of around 10 dB for the worst element at 0 steering angle, and at 60 steering angle it was 5dB for the worst element and edge frequency. The complete TRM was only in the design stage in this master thesis, the size of the design resulted in the dimensions 250x117mm. In conclusion, the power requirement for 700W per module was met and the power in 1 dB compression were 953W with losses after the power amplifier accounted for. The linear power from the amplifier yielded a power of 800W, also meeting the power requirements. The antenna did not meet the requirement of 10 dB return loss, however, the antenna design in itself resulted in a small and light antenna array which was desirable attributes in this project. The requirement for the size of the complete TRM was 250 mm x 120 mm and this requirement was met in the design stage for this project. There were two different phase shifters in this project and the conclusion was to go for the phase shifter designed with transmission lines instead of the IC circuit. This decision was made because the designed phase shifter had a lower and more even insertion loss. It also had a more predicable phase shift for 180°.



Publikationen registrerades 2018-10-10. Den ändrades senast 2018-10-10

CPL ID: 256120

Detta är en tjänst från Chalmers bibliotek