Countermeasure methods for high power microwave pulses /

Thesis Type: Postgraduate

Institution Of The Thesis: Orta Doğu Teknik Üniversitesi, Faculty of Engineering, Department of Electrical and Electronics Engineering, Turkey

Approval Date: 2014


Supervisor: ŞİMŞEK DEMİR


In this thesis, a limiter structure is investigated to decrease the effects of High Power Microwave (HPM) pulses coupled from front-door by using vanadium dioxide (VO2). To prove that vanadium dioxide can be used as an RF limiter, this structure is examined, realized and measured. Firstly, susceptibility of LNA to HPM pulses is investigated by an experimental setup to determine the destruction threshold levels of LNA technology for direct injection of HPM pulses. Based on these threshold levels, diode limiter technology is examined in terms of power handling capacity and response time. The behaviors of two diode limiters against the HPM attacks are studied to have a general idea about diode technology. As a result of this study, for pulses having high amplitudes and short pulse widths, diode technology is not enough to protect the vulnerable front-end devices like LNA’s. Therefore, another limiter structure is needed to handle the HPM pulses. To produce a VO2 limiter, VO2 material is synthesized by using two hydrothermal methods. Then, these produced samples are characterized with X-ray diffraction technique and extraction of resistance characteristics. With this obtained material, a limiter is realized and performance of the limiter is measured and discussed.