Design Of Loop Antenna For Wireless Capsule Endoscope System

The rapid development of modern medical technology,in the detection and treatment of stomach diseases,the traditional gastroscope detection of patients suffering,easy to cause damage and patient resistance check.The wireless capsule endoscope is an emerging non-invasive and painless digestive tract diagnostic technology,which is a comprehensive system integrating photoelectric engineering,image processing,information communication and biomedical technology.The fine and minute components are composed,including a camera,a battery,an antenna,etc.,wherein the wireless communication antenna transmits the data image collected by the wireless capsule endoscope in the human body to the receiving device outside the human body,so the performance of the antenna directly affects The quality of wireless information transmission,the antenna is an important part of the wireless capsule endoscope system.The emergence of wireless capsule endoscopes provides a new choice for modern medical digestive tract diagnosis.This thesis studies the loop antenna used in wireless capsule endoscopes.The main research work is as follows:First,a broadband ring capsule antenna was researched and designed.The antenna is based on a flexible substrate polyimide.The working frequency band is 400 MHz and 2.45 GHz,which are commonly used in capsule antennas.The size is 14 mm*31.4 mm and the thickness is 0.1 mm.The loop antenna has a simple structure,a small occupied area,and a wide frequency band,which improves the performance of the capsule antenna.The antenna has a bandwidth of 2.82 GHz and a gain of-24.7 dB.The simulation and test environment are both simulated in the human body,and the application requirements of the electronic capsule system are achieved in both working frequency bands.On this basis,the method of increasing the bandwidth by using the wideband characteristics of the loop antenna is studied.A monopole antenna loaded with a loop antenna applied to an electronic capsule is designed.The antenna is based on a flexible substrate polyimide with a working frequency of 400 MHz,a size of 14 mm*31.4 mm,a thickness of 0.1 mm,and a bandwidth of about 244 MHz,which is almost double the bandwidth of 102 MHz when no loop antenna is added.The gain is-20 dB,and the gain change is small when the loop antenna is not added,which achieves the purpose of increasing the bandwidth.The simulation and test environment are both simulated in the human body.Finally,this thesis summarizes the previous work and various shortcomings in the design,and puts forward the research direction and the required research work.