Maksimalno glatki prostorni filtri

master's thesis

• Title (english): Maximally Flat Spatial Filters
• Author: Andrea Jelavić Šako
• Mentor: Goran Molnar (mentor)
• Committee member: Goran Molnar (predsjednik povjerenstva)
• Committee member: Mladen Vučić (član povjerenstva)
• Committee member: Damir Seršić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Electrical Engineering and Computing; Zagreb
• Defense date and country: 2020-07-10, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Computing
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Electrical Engineering

Abstract

Prostorno razmaknute antene po unaprijed danom rasporedu predstavljaju prostorne filtre. Najpoznatiji raspored je uniformna razdioba antena na pravcu. Takvi prostorni filtri nazivaju se uniformni antenski nizovi. Najčešći pristup u dizajnu uskokutnih uniformnih antenskih nizova je onaj primjenom metode otvora. U ovom pristupu, posebna pažnja se posvećuje otvorima s malim dinamičkim rasponom koeficijenata te otvorima čiji dijagrami zračenja imaju danu razinu bočnih latica. Korištenjem metode otvora, u ovom radu predložene su dvije klase prostornih filtara koje se temelje na maksimalno glatkoj aproksimaciji u prostornoj i azimutnoj domeni. Za klasu filtara temeljenu na aproksimaciji u prostornoj domeni, dan je jednostavan postupak za dizajn maksimalno glatkog otvora koji za dani dinamički raspon koeficijenata daje dijagram zračenja s najmanjom razinom bočnih latica. Za klasu filtara temeljenu na aproksimaciji u azimutnoj domeni, dan je analitički postupak za dizajn otvora koji za danu razinu bočnih latica daje glavnu laticu s maksimalno glatkim vrhom te prihvatljivim dinamičkim rasponom koeficijenata. Za obje klase maksimalno glatkih filtara, određene su njihove značajke te su uspoređene sa značajkama postojećih prostornih filtara.

Abstract (english)

According to a predetermined arrangement, spatially distanced antennas represent spatial filters. The most common arrangement is uniformly distanced antennas. These types of spatial filters are called uniform linear antenna arrays. The most common approach in the design of narrowband uniform antenna arrays is one using the windowing method. In this approach, special attention is dedicated to windows with small dynamic range ratio values and the ones whose radiation pattern has a predetermined sidelobe level. The methods proposed in this paper are two classes of spatial filters based on maximally flat approximation in spatial and azimuth domain. The approximation in the spatial domain implies the design of a maximally flat top which for a given DRR gives a minimum sidelobe level. For the filters based on approximation in azimuth domain, the design is based on a window which for a given sidelobe level achieves a flat top of the main lobe and satisfactory DRR. For both classes of maximally flat filters, the main features were determined and compared with the features of existing space filters.

• Keywords: prostorni filtri; dijagram zračenja; antenski nizovi; maksimalno glatka aproksimacija; dinamički raspon koeficijenata; razina bočnih latica
• Keywords (english): spatial filters; beampattern; antenna arrays; maximally flat approximation; dynamic range ratio; sidelobe level
• Language: croatian
• URN:NBN: urn:nbn:hr:168:277134
• Study programme: Title: Electrical Engineering and Information Technology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka elektrotehnike i informacijske tehnologije (magistar/magistra inženjer/inženjerka elektrotehnike i informacijske tehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2023-01-13 10:05:57