Intrabody communication based on capacitive method

doctoral thesis

• Title (croatian): Prijenos signala ljudskim tijelom zasnovan na kapacitivnoj metodi
• Author: Željka Lučev Vasić; MBZ: 303144
• Mentor: Mario Cifrek (mentor)
• Committee member: Mario Cifrek (član povjerenstva)
• Granter: University of Zagreb; Faculty of Electrical Engineering and Computing; (Department of Electronic Systems and Information Processing); Zagreb
• Defense date and country: 2014, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Computing; Data Processing
• Universal decimal classification (UDC): 621.3 - Electrical engineering

Abstract

In an intrabody communication (IBC) system the human body is used as a part of a communication channel between the transmitters and receivers placed on the surface of the skin, in its vicinity, or implanted inside the user’s body. IBC systems use lower frequency band than standard wireless systems, and they have lower power consumption and lower range. Possible applications of IBC technology are broad: from biotelemetry and medicine to the communication between various electronic devices and security systems. This doctoral thesis is focused on analysis and modelling of a transmission path of an intrabody communication system, and on the design of very low power transmitters and receivers. Transmission characteristic of the capacitive IBC system depends on the tissue characteristics and signal path, defined by the positions of the transmitter and receiver, placement of the transmitter and receiver electrodes on the body, and surrounding environment. A procedure proposed for measuring IBC channel transmission characteristic in the frequency range from 100 kHz to 100 MHz provides galvanic decoupling of the measuring equipment from the IBC channel. Using a proposed measurement procedure, the influences of the type, size, and position of the transmitter and receiver electrodes, and the influence of the environment were investigated and theoretically explained. The conclusions were confirmed by the in vivo measurements in a realistic communication scenario, on a larger number of test subjects with different anatomical characteristics, for several static and dynamic body positions. Employing the measurement results analysis, a model of a capacitive intrabody communication system operating at discrete frequencies up to 100 MHz, based on lumped parameters and transmission lines was created. The guidelines for IBC transmitter and receiver design, optimal in the sense of power requirements, signal transmission quality, and dimensions were given, based on the developed model and in vivo measurements. Finally, the results of this thesis were applied in the development of an operating IBC system prototype.

Abstract (croatian)

Sustavi za prijenos signala ljudskim tijelom (engl. intrabody communication, IBC) koriste čovjeka kao dio komunikacijskog kanala između odašiljača i prijamnika smještenih na površinu tijela, u neposrednu blizinu tijela, ili implantiranih unutar tijela korisnika. IBC sustavi rade na nižim frekvencijama nego standardni bežični sustavi i sukladno tome imaju manju potrošnju i manji domet. Moguće primjene IBC tehnologije su vrlo široke: od biotelemetrije i medicine s jedne strane do komunikacije između različitih elektroničkih uređaja i sigurnosnih sustava s druge strane. Ova doktorska disertacija se bavi analizom i modeliranjem prijenosnog puta kapacitivnog sustava za prijenos signala ljudskim tijelom, te razvojem odašiljača i prijamnika vrlo niske potrošnje. Prijenosna karakteristika IBC sustava ovisi o svojstvima tkiva i putu signala definiranom položajem odašiljača i prijamnika, načinom spajanja odašiljačkih i prijamnih elektroda na tijelo, te karakteristikama okoline. Postupak mjerenja prijenosne karakteritike IBC sustava u frekvencijskom području od 100 kHz do 100 MHz omogućava galvansko odvajanje mjerne opreme od IBC sustava. Tim postupkom su ispitani utjecaji tipa, vrste i položaja odašiljačkih i prijamnih elektroda, te utjecaj bliže okoline, koji je i teoretski objašnjen. Zaključci su potvrđeni in vivo mjerenjima provedenim u realnim uvjetima na većem broju ispitanika različitih anatomskih obilježja, za nekoliko statičkih i dinamičkih položaja tijela. Definirane su smjernice za izbor radne frekvencije i izlazne snage odašiljača te osjetljivosti prijamnika, temeljene na razvijenom modelu i provedenim mjerenjima. Rezultati istraživanja su primijenjeni prilikom razvoja prototipa kapacitivnog sustava za prijenos signala ljudskim tijelom.

• Keywords: intrabody communication (IBC); capacitive coupling; transmission characteristic; human body positions; human body movements; human body modelling; lumped parameters; transmission lines; electrode configuration; transceiver design
• Keywords (croatian): prijenos signala ljudskim tijelom; prijenosna karakteristika; položaji ljudskog tijela; pokreti ljudskog tijela; modeliranje ljudskog tijela; koncentrirani parametri; prijenosne linije; konfiguracije elektroda; projektiranje primopredajnika
• Language: english
• URN:NBN: urn:nbn:hr:168:761582
• 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
• Extent: 164 str. ; 30 cm.
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2019-04-17 14:26:03