Thesis Type: Doctorate
Institution Of The Thesis: Orta Doğu Teknik Üniversitesi, Faculty of Engineering, Department of Electrical and Electronics Engineering, Turkey
Approval Date: 2012
Student: PEJMAN MOHAMMADI
Supervisor: ŞİMŞEK DEMİRAbstract:
Substrate Integrated Waveguide (SIW) technology has been used in designing and fabricating SIW n-way power dividers. In this thesis employing this technology three-port and ﬁve-port SIW power dividers are designed and fabricated. These structures are compact in size and the design procedure can be expanded into n-port power dividers. These structures are used with microstrip transition parts however measurement of S-parameters of the main structure are required for comparison. This is carried out with a special algorithm based on TRL calibration method. This method is general for reconstructing the S-parameters of the n-port network. For the three-port SIW power divider the measured return loss is below 10 dB and transmission is measured between -3.5 dB and -4 dB over a frequency band from 9 GHz to 11 GHz. The measured amplitude balance is less than ±0.5 dB from 9.5 GHz to 11 GHz and the measured phase diﬀerence between ∠S21 and ∠S31 is about 4 degrees. There is a good agreement between simulation and measurement results over the frequency band from 9.5 GHz to 10.5 GHz for ﬁve-port SIW power divider. Based on the total loss mechanisms in SIW structure low loss SIW three-port and ﬁve-port power dividers have been designed. A three-port partially ﬁlled SIW power divider has been constructed. Its measurement results show that transmissions are between -3 dB and -3.5 dB from 8.75 GHz to 10 GHz and the return loss is less than 10 dB in the same frequency band. The measured amplitude balance is less than ±0.2 dB over frequency band from 8.75 GHz to 10 GHz and the measured phase difference between ∠S21 and ∠S31 is about 4 degrees.