碩士 / 國立中正大學 / 電機工程研究所 / 103 / In this thesis, a miniaturized antenna design for minimally invasive surgical positioning system is proposed. Comparing to the traditional surgery, the benefits of minimally invasive surgery include increased safety, decreased scarring and faster recovery. However, the limited field of view also brings difficulty, which motivates this work.
Four antennas, including loop antenna and slot antenna, have been designed for surgical instruments with very restricted size limit. In order to carry out the in-body antenna measurement, the electrical characteristic of human tissues, including permittivity and conductivity, need to be considered at the early phase of design. Therefore, the simulated human tissue liquid is also deployed in this work with testing method being discussed. The designed antenna is measured in the air and in the tissue liquid in either plane form or curved form.
According to the result, the operating frequency is from 2.29 GHz to 3.2 GHz, but the radiation pattern isn’t omnidirectional totally. There is an voltage control oscillator(VCO) that be used, the tunable voltage is from 0 V to 10 V, the output frequency is from 2.25 GHz to 2.5 GHz, but the radiation patterns are not as omni-directional as what we expect due to multiple loading effects. A commercial voltage control oscillator (VCO) IC is used as signal source, where that the output frequency is from 2.25 GHz to 2.5 GHz under 0V to 10 V control voltage. The measured output power is -33.8 dBm after being integrated with surgical instrument and antenna is placed in the simulated tissue.
The algorithm and the hardware circuits of the positioning system are briefly introduced in chapter three. The center frequency of received antenna is 2.298 GHz,
the axial ratio is smaller than 3 dB within the spacial range from -35° to 35°. The tunable phase of phase shifter is 0° to 180°.
The demonstrations of the entire positioning system are described in chapter four. For 1-D positioning, the error angle is less than 4 degrees when the accumulation probability is 80%. When placing the simulated tissue and foam mattress, the error angle is still less than five degrees at 80% accumulation probability. In 2-D positioning, we use pork instead of simulated tissue, the maximum error distance is 2.5 cm while the average error distance is 0.69 cm.
| Identifer | oai:union.ndltd.org:TW/103CCU00442060 |
| Date | January 2015 |
| Creators | Peng-Yu Chen, 陳鵬宇 |
| Contributors | Chia-Chan Chang, 張嘉展 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 129 |
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