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Sensing signals of a sensor in digestive tract
Raška, Marek ; Láčík, Jaroslav (referee) ; Raida, Zbyněk (advisor)
Wireless capsule endoscopy (WCE) is a system for capturing images of human digestive tract for medical purposes. The antenna is one of the most important parts of the system. In this report, I present a solution for a system operating in the 2.4 GHz and 915 MHz ISM band. The capsule transmitter contains a conformal loop antenna placed on its outer wall. The planar monopole with a partial ground is used as a receiver. The systems have been verified by numerical simulations with a phantom representing digestive tract. The transmitting modules have the bandwidth of several GHz according to simulations. This allows the antenna to tolerate various effects of living tissues. The receiving antennas have the bandwidth of hundreds of MHz. The path loss of the radio link between antennas operating in 2,4 GHz band is lower than 94 dB for any capsule orientation and location. This does not ensure a sufficient signal strength at the receiving antenna. In contrast, the system operating at 915 MHz ensures sufficient signal level at the receiver.
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Modeling of the thermal effects on living tissue during electroporation process
Kafka, Roman ; Cipín, Radoslav (referee) ; Červinka, Dalibor (advisor)
The work deals with the current state of knowledge of heat transfer in living tissue. It is described here what the distribution of heat is affected with and the existing calculation options. For solving Pennes equation using finite element method COMSOL Multiphysics 5.4 is used. From the current state of the published studies, three are selected and described, each using a different approach. Based on the benefit of each of the studies described, a simple model of its own that simulates an ablation catheter attached to cardiac tissue is solved. A change in electrical conductivity as a function of the electric field intensity is taken into account, but there is also a comparison with anisotropic tissue that has electrical conductivity in different directions. The result of the calculation is voltage distribution, density of electric current and losses, temperature distribution in the model at several time points and graph of temperature development over time.
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Receiving Signals From A Sensor In The Digestive Tract
Raška, Marek
Wireless capsule endoscopy is a system for capturing images of human digestive tract for medical purposes. In this report, I present an antenna solution for a system operating in the 915 MHz ISM band. The capsule transmitter contains a conformal slot loop antenna placed on its outer wall. The planar monopole with a partial ground is used as a receiver. The system has been verified by numerical simulations with a phantom representing part of a human body. Low path loss of the radio link between antennas ensures sufficient signal strength at the receiver for any capsule orientation and location.
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Modeling of the thermal effects on living tissue during electroporation process
Kafka, Roman ; Cipín, Radoslav (referee) ; Červinka, Dalibor (advisor)
The work deals with the current state of knowledge of heat transfer in living tissue. It is described here what the distribution of heat is affected with and the existing calculation options. For solving Pennes equation using finite element method COMSOL Multiphysics 5.4 is used. From the current state of the published studies, three are selected and described, each using a different approach. Based on the benefit of each of the studies described, a simple model of its own that simulates an ablation catheter attached to cardiac tissue is solved. A change in electrical conductivity as a function of the electric field intensity is taken into account, but there is also a comparison with anisotropic tissue that has electrical conductivity in different directions. The result of the calculation is voltage distribution, density of electric current and losses, temperature distribution in the model at several time points and graph of temperature development over time.
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|
|
Sensing signals of a sensor in digestive tract
Raška, Marek ; Láčík, Jaroslav (referee) ; Raida, Zbyněk (advisor)
Wireless capsule endoscopy (WCE) is a system for capturing images of human digestive tract for medical purposes. The antenna is one of the most important parts of the system. In this report, I present a solution for a system operating in the 2.4 GHz and 915 MHz ISM band. The capsule transmitter contains a conformal loop antenna placed on its outer wall. The planar monopole with a partial ground is used as a receiver. The systems have been verified by numerical simulations with a phantom representing digestive tract. The transmitting modules have the bandwidth of several GHz according to simulations. This allows the antenna to tolerate various effects of living tissues. The receiving antennas have the bandwidth of hundreds of MHz. The path loss of the radio link between antennas operating in 2,4 GHz band is lower than 94 dB for any capsule orientation and location. This does not ensure a sufficient signal strength at the receiving antenna. In contrast, the system operating at 915 MHz ensures sufficient signal level at the receiver.
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