Research On Implantable Radio-Telemetry System For Monitoring Animal Physiological Parameters Based On Wireless Power Transmission Technology

Implantable radio-telemetry which can be used to detect physiological parameters of unconstrained animals is one of the fastest growing branches of biomedical measuring technologies.It has great significance on the research of organism itself and the efficacy evaluation of drugs, artificial organs and auxiliary equipments.In addition,measurement accuracy greatly improves because the measuring device implanted in vivo can be able to work in the favorable environment with constant temperature and less interference.This thesis is based on the project―Research of animal physiological parameter detection system‖funded by National Natural Science Foundation(Granted Number:30800235) for Shanghai Zenda Medical Device Co.,Ltd.It makes further study on the implantable detection system for monitoring animal physiological parameters.This thesis proposes the design of an implantable radio-telemetry system for monitoring animal physiological parameters based on wireless power transmission technology.The system contains wireless power transmission device,implantable miniature electronic capsule,data logger and data processing software.Wireless power transmission device can provide electric energy for capsule so that animals are kept from suffering caused by frequent replacements of batteries.Implantable capsule is able to detect ECG,blood pressure and body temperature of animals and transmit measured data wirelessly to data logger in vitro.The data are received,saved and displayed by the data logger.Data processing software on PC reads and processes the data saved by data logger,then draws the waveform of physiological parameters.This thesis introduces the structure of vivo and vitro devices,studies the critical technologies in the design of the system.Wireless energy transmission technology uses rectangular solenoid transmitting coil to provide energy for the capsule.Three-dimensional coil in the capsule receives electric energy and makes the capsule work normally.The capsule that integrates signal acquisition module,filtering module,amplification module and AD conversion module transmits data wirelessly by using RF chip.Data logger integrates wireless data reception module,data storage module and LCD display module.Data processing software is programmed by MATLAB,it integrates data reading module and figure drawing module.Besides,it provides graphical interface for users.The performance of the system is verified through simulation experiments and animal experiments.In the simulation experiments,direct current power supply method and wireless energy supply method are separately used to provide energy for capsule.The result of the simulation experiments shows that physiological parameters can be detected accurately when capsule gets energy from direct current power supply.It also shows that the wireless power can meet the energy requirements of the capsule.During wireless energy transmission,data logger is able to receive data transmitted from the capsule,simulation ECG signal can only be detected when the signal wires are shielded.In the animal experiments,a New Zealand rabbit is used as experimental animal,blood pressure and body temperature are detected but ECG signal is submerged by the electromagnetic field.In this thesis,an implantable radio-telemetry system based on wireless power transmission technology is designed and realized for long-term monitoring animal physiological parameters continuously.The capsule is onlyΦ13×30mm in size and weights 6.38g with about 150mW power consumption.A New Zealand rabbit is used in the vivo experiment,the detected body temperature is 37.2-37.3°C with 0.1°C baseline noise,the detected blood pressure is 74-83mmHg with 3mmHg baseline noise.In conclusion,this thesis puts forward the innovation in this system and proposes future research direction of the system,it provides references for further research.