Raspodijeljeni algoritam za lokalizaciju u neusidrenoj mreži određivanjem smjera dolaska signala

doctoral thesis

• Title (english): Distributed algorithm for anchor-free network localization using angle of arrival
• Author: Damir Arbula
• Mentor: Zdenko Kovačić (mentor)
• Committee member: Stjepan Bogdan (predsjednik povjerenstva)
• Committee member: Zdenko Kovačić (član povjerenstva)
• Committee member: Mario Essert (član povjerenstva)
• Granter: University of Zagreb; Faculty of Electrical Engineering and Computing; (Department of Control and Computer Engineering); Zagreb
• Defense date and country: 2008-10-30, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Electrical Engineering; Automation and Robotics
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Electrical Engineering; Telecommunications and Informatics
• Universal decimal classification (UDC): 004 - Computer science and technology. Computing. Data processing ; 654 - Telecommunication and telecontrol

Abstract

Problem lokalizacije u bežičnim mrežama osjetila i ad hoc bežičnim mrežama rješiv je korištenjem izmjerenih udaljenosti ili azimuta između susjednih čvorova. Uz pomoć tih ograničenja rješiv je jedino problem relativne lokalizacije, dok za specifičniji problem apsolutne lokalizacije potreban je skup čvorova - sidara kojima je poznata apsolutna lokacija. U ovom radu obrađen je pristup projektiranja i evaluacije raspodijeljenog algoritma za lokalizaciju u neusidrenoj mreži. Algoritam se koristi samo sa azimutima između čvorova susjeda, izmjerenim unutar relativnog koordinatnog sustava samog čvora nepoznate orijentacije. Algoritam se temelji na podjeli mreže u grozdove. Nakon što se lokaliziraju inicijalni čvorovi, njihovim međusobnim spajanjem lokalizira se cjelokupna mreža. Korištenjem teorije krutosti grafova definirane su nove mrežne strukture i njihovi odnosi, na taj način da algoritam može odrediti relativne lokacije maksimalnog broja čvorova za zadani broj izmjerenih azimuta. Performanse algoritma ispitivane su kroz niz simulacija, a dobiveni rezultati su usporedivi sa centraliziranom verzijom algoritma. Dodatnom analizom pokazalo se kako performanse ne ovise bitno o putu i poretku kojim se spajaju grozdovi. Usporedbom performansi sa Cramér Rao limitom pokazuje se kako pogreška uzrokovana algoritmom čini 30% – 50% ukupne pogreške lokalizacije.

Abstract (english)

A localization problem in wireless sensor and ad hoc networks can be solved using measured distances and/or directions between neighboring nodes as constraints. With internode constraints only general the relative localization problem can be solved as for more specific absolute positions, a set of prelocalized nodes called anchors is needed. In this thesis approach in design and evaluation of a distributed anchor-free localization algorithm is presented. It is using only direction constraints relative to node’s coordinate system as their orientations are assumed to be unknown. The algorithm is based on division of a network in clusters. After initial clusters are localized, by stitching them together it can localize whole network. Using graph rigidity theory we defined new structures and their relationships so the algorithm can provide relative locations to maximum number of nodes for given number of constraints. The performance was evaluated through simulations and obtained results are similar to centralized version of algorithm. Additional analysis showed that the performance is not dependant on a path and order used for cluster stitching. By comparing the performance to the Cramér Rao bound, it is revealed that the error induced by the algorithm represents 30% – 50% of the total localization error.

• Keywords: bežične mreže osjetila; ad hoc mreže; teorija krutosti grafova; lokalizacija; kut dolaska signala; raspodijeljeni algoritmi
• Keywords (english): wireless sensor networks; ad hoc networks; graph rigidity theory; localization; angle of arrival; distributed algorithms
• Language: croatian
• URN:NBN: urn:nbn:hr:168:057073
• Study programme: Title: Electrical Engineering and Computing; Study programme type: university; Study level: postgraduate; Academic / professional title: Doktor znanosti elektrotehnike i računarstva (Doktor znanosti elektrotehnike i računarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2020-05-31 08:39:05