Rapid development of wireless communications has led to the excessive use of wireless equipments. The purpose of communication is achieved through the transmission and reception of electromagnetic waves by the wireless equipments. Living in the environment of massive electromagnetic exposure coming from these wireless equipments, the health issue is a growing concern among the people who use the equipments and also the general public. The GSM communication system is the most widely used segment of wireless communications currently in Taiwan. The user of the mobile terminal (handset) is in close proximity to the radiating antenna. Most of the EM radiation emitting from the antenna will pass through the body of the user and be absorbed by the human tissue. It is therefore important to consider possible health hazards due to this type of EM exposure.
Among all the possible biological effects caused by EM exposure, the heating effect is the most significant and its influence on biological tissues is proven. Currently most countries require the handsets to be tested for SAR values before the handsets are ready for purchasing on the markets. SAR tests require the utilization of expensive measurement facilities. Moreover, even though the phantom used for SAR measurement is prepared according to standards, theoretically the phantom is still not identical to the anatomical constituents of the human head. Henceforth, it is necessary to investigate the field distribution inside the human head, using an anatomical model, due to the exposure of radiation coming from the handset antennas from the theoretical point of view. The whole human body is an inhomogeneous lossy dielectrics as far as EM wave propagation is concerned. This feature renders the problem easy to tackle using the FDTD numerical method.
This thesis presents a method to build up a numerical human head model suitable for the FDTD analysis using data set from the ¡§visible human¡¨ project readily available from the internet. The thesis then investigates the field distribution inside the human head, under the exposure of the quarter-wavelength monopole antenna on a dielectric covered metal box. Temperature increases due to the absorption of EM energy by the human head will then be deducted from the bioheat equation.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0726102-002528 |
| Date | 26 July 2002 |
| Creators | Guo, Zhi-Ming |
| Contributors | Ken-Huang Lin, Tzong-Lin Wu, Chih-Wen Kuo, Jen-Fen Huang |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0726102-002528 |
| Rights | unrestricted, Copyright information available at source archive |
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