Study Of Ingestible Temperature Monitoring Capsule System

Continues developments of integrated circuit and communication technology make the demands for various kinds of wireless medical devices with the characteristics of in-vitro communication and in-vivo communication being increasing rapidly.However,on account of the mutual coupling between wireless devices and human body,there exists uncertainty in communication stability and robustness.Hence,it is of great significance to carry on studies on capsule antennas satisfying the requirement for system reliability.This paper presents two kinds of capsule antennas suitable for the application of human body temperature monitoring,which aims at miniaturization,biological compatibility,security,and performance stability.The main works of this paper are as follows:(1)A kind of capsule antenna similar to the PIFA structure is presented.The electromagnetic radiation performance of the capsule antenna is analyzed,and the antenna performance stability is also discussed.The system consisting of wireless transceiver circuit and matching circuits is built.Finally,the integrated capsule system is put into the mixture solution to conduct the measurement of communication system and the function is realized.The experimental result proves the feasibility of the proposed antenna.(2)To further reduce the capsule volume,a conformal differential-fed capsule antenna is proposed.The accurate human body model is imported in the Sim4 life to verify the antenna performance.Some aspects affecting the antenna performance are also analyzed and discussed.Finally,an entire capsule communication link is built and the function that real-time temperature data are monitored is realized.In addition,the communication ability of the system is evaluated,which lays a foundation for further engineering application of this system.In short,two types of ingestible wireless temperature monitoring capsule are designed on the basis of full consideration about the characteristics of in-body environment in this paper.Some beneficial explorations have been made on the miniaturization and performance stability.A wireless capsule system which is smaller than that of founded literatures is achieved.The proposed solution has a good potential in engineering.