Stabilnost aktivnih radiofrekvencijskih sustava s prostorno-vremenskom simetrijom

master's thesis

• Title (english): Stability of Active RF Systems with Parity-time Symmetry
• Author: Katjana Krhač
• Mentor: Silvio Hrabar (mentor)
• Committee member: Silvio Hrabar (predsjednik povjerenstva)
• Committee member: Juraj Bartolić (član povjerenstva)
• Committee member: Igor Krois (član povjerenstva)
• Granter: University of Zagreb; Faculty of Electrical Engineering and Computing; Zagreb
• Defense date and country: 2016-07-11, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Electrical Engineering

Abstract

Načinjen je kratak pregled literature o aktivnim metamaterijalima i radiofrekvencijskim sustavima koji oponašaju kvantne sustave s prostorno-vremenskom (PT) simetrijom. Analizirana je mogućnost praktične izvedbe jednodimenzionalnog PT sustava koji oponaša pozitivnu i negativnu rezistivnu metapovršinu pomoću prijenosne linije zaključene pozitivnim i negativnim otporom.
Detaljnije je objašnjen i analiziran negativni otpor izveden koristeći negativni konverter impedancije pomoću operacijskog pojačala s otporom u pozitivnoj povratnoj vezi. Također je detaljno prikazana analiza stabilnosti prijenosne linije zaključene pozitivnim i negativnim otporom koristeći ADS.
Teorijski izračuni vezani uz negativni otpor i liniju zaključenu pozitivnim i negativnim otporom provjereni su mjerenjima na laboratorijskom prototipu. Mjerenjima na vektorskom analizatoru mreža pokazan je stvarni iznos otpora kojeg generira prototip negativnog otpora. Mjerenjem linije zaključene pozitivnim i negativnim otporom na osciloskopu provjerena je stabilnost. Rezultati mjerenja su u potpunosti potvrdili teorijske izračune vezane uz uvjete i područja stabilnosti.

Abstract (english)

A short and general overview about active metamaterials and RF systems with PT-symmetry has been given. The possibility of practical performance of one-dimensional PT system, which mimics positive and negative resistive meta-surface with help of transmission line terminated with positive and negative resistance was analyzed.
Negative resistance achieved through using negative impedance converter with operational amplifier with resistance in positive feedback was explained and analyzed in details. In addition, detailed analysis regarding stability of transmission line terminated with positive and negative resistance was verified using Advanced Design System - ADS.
Theoretical calculations related to negative resistance and line terminated with positive and negative resistance were checked using measurements on laboratory prototype. Measurements using vector network analyzer showed real amount of resistance that prototype of negative resistance generates. Stability of the transmission line terminated with positive and negative resistance was checked by measurements on the oscilloscope. Results of measurements fully confirmed theoretical calculations regarding of requirements and area of stability.

• Keywords: metamaterijali; ne-Fosterovi elementi; negativni konverter impedancije; prostorno-vremenska simetrija; negativni otpor; stabilnost
• Keywords (english): metamaterials; non-Foster elements; negative impedance converter; parity-time symmetry; negative resistance; stability
• Language: croatian
• URN:NBN: urn:nbn:hr:168:389155
• Study programme: Title: Information and Communication Technology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka informacijske i komunikacijske tehnologije (magistar/magistra inženjer/inženjerka informacijske i komunikacijske tehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2018-02-06 09:54:38