Spectrally and energy efficient ultra-wideband pulses based on spectrum shaping

doctoral thesis

• Title (croatian): Spektralno i energetski učinkoviti ultra-širokopojasni pulsovi temeljeni na oblikovanju spektra
• Author: Ante Miloš; MBZ: 8109
• Mentor: Mladen Vučić (mentor)
• Mentor: Goran Molnar (komentor)
• Committee member: Damir Seršić (predsjednik povjerenstva)
• Committee member: Davor Petrinović (član povjerenstva)
• Committee member: Miroslav Vrankić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Electrical Engineering and Computing; Zagreb
• Defense date and country: 2024-03-08, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Electrical Engineering
• Universal decimal classification (UDC): 621.3 - Electrical engineering

Abstract

Ultra-wideband (UWB) radio utilizes very short pulses to transmit data. These pulses should efficiently fill a given spectral mask and be well concentrated in the time domain. Common UWB pulses exploit Gaussian derivatives. These derivatives are well concentrated in the time domain, but they do not exploit the area under the mask efficiently. In the dissertation, two methods for the design of spectrally and energy efficient pulses based on the Gaussian pulse and its derivatives are presented. The first method is based on sharpening of the magnitude spectrum of an arbitrary Gaussian derivative by applying the Kaiser-Hamming polynomials. Such sharpening offers controllable flatness at the top of the magnitude spectrum as well as controllable steepness in spectrum's transition regions. The second method is inspired by Gaussian derivatives, in which the Gaussian is weighted by Hermite polynomials. In the dissertation, optimum weighting polynomials are constructed, which ensure maximum flatness at the peak of pulse’s magnitude spectrum. Compared to other Gaussian-based waveforms, both methods bring the pulses with significantly higher spectral efficiency and only slightly lower energy concentration. The approximation of the ideal UWB waveforms by using impulse responses of continuous-time filters is also considered. The transfer functions of these filters suitable for shaping various conventional as well as the proposed UWB pulses are provided.

Abstract (croatian)

Ultra-širokopojasni (ultra-wideband, UWB) radio koristi pulsove kratkog trajanja za prijenos informacija. Ovi pulsovi moraju učinkovito popunjavati zadanu spektralnu masku te biti koncentrirani u vremenu. Često korišteni pulsovi temelje se na Gaussovim derivacijama. Ove derivacije su dobro vremenski koncentrirane, ali ne iskorištavaju učinkovito područje pod maskom. U disertaciji su predložene dvije metode za dizajn spektralno i energetski učinkovitih pulsova temeljenih na Gaussovom pulsu i njegovim derivacijama. Prva metoda se temelji na izoštravanju amplitudnih spektara Gaussovih derivacija Kaiser-Hammingovim polinomima. Takvo izoštravanje nudi kontroliranje glatkoće u maksimumu amplitudnog spektra kao i kontroliranje nagiba njegovog prijelaznog područja. Druga metoda je inspirirana Gaussovim derivacijama, u kojima je Gaussova funkcija otežana Hermitovim polinomima. U disertaciji je predložen optimalan težinski polinom koji osigurava maksimalnu glatkoću u vrhu amplitudnog spektra pulsa. Komparirajući dobivene pulsove s drugim pulsovima temeljenim na Gaussovoj funkciji, obje metode nude značajno veće spektralne učinkovitosti s tek nešto slabijom energetskom koncentracijom. Konačno, razmatrana je aproksimacija idealnih pulsova pomoću impulsnih odziva vremenski kontinuiranih filtara. Dane su prijenosne funkcije ovih filtara pogodne za oblikovanje raznih konvencionalnih te predloženih UWB pulsova.

• Keywords: Gaussian derivatives; impulse response approximation; maximally flat; optimum waveforms; polynomial sharpening; pulse shaping; time-domain synthesis; ultra-wideband (UWB) systems
• Keywords (croatian): Gaussove derivacije; aproksimacija impulsnog odziva; maksimalno ravno; optimum valni oblici; izoštravanje polinoma; oblikovanje impulsa; sinteza u vremenskoj domeni; ultraširokopojasni (UWB) sustavi
• Language: english
• URN:NBN: urn:nbn:hr:168:400852
• Promotion: 2024
• Study programme: Title: Doctoral study programme "Electrical Engineering and Computing"; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, po-dručje tehničkih znanosti (doktor/doktorica znanosti, po-dručje tehničkih znanosti)
• Type of resource: Text
• Extent: 109 str. : graf. prikazi
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-05-10 09:37:36