1. IntroductionNowadays, digital electronic devices have been used to make many things easier and better. Personal computers have been successful in helping people with their work and providing them with entertainment. It is therefore not surprising that people are now considering integrating electronic systems more into the medical field, so that their service is cheaper and easier to use. accessible and of better quality. Some patients with chronic illnesses sometimes need to be closely monitored by a medical team. By connecting patients to appropriate sensors capable of transmitting data over the network, it is possible for patients to have long-term monitoring without the need for a long and expensive hospital stay. For long-term and long-distance monitoring, implantable sensors are desirable. Implantable sensors are inserted into the human body so as not to disrupt patient activities. Of course, implanted devices must be able to communicate with the outside world without using wires because "wires that pass through the skin are a source of infection, can cause injury (if pulled or bumped), and are often uncomfortable for the patient”. [1]. Besides the monitoring purpose, implantable devices can also be used for more complex prescription applications, such as an implantable drug delivery system, an implantable insulin pump, etc. Figure 1.1 Wireless Body Area NetworkThe network for medical applications around the patient's body is called a Wireless Body Area Network (WBAN), seen in Figure 1.1. A WBAN consists of sensors (either implanted or portable) and a gateway node. The gateway node in the figure is called the Personnel Control Unit (PCU), although other terminologies such as Body Control Unit...... middle of paper ......Nieto, Fundamentals and applications of RFID design. London: CRC Press, 2010.[7] Z. Yang et al, “Wireless Power and Data Telemetry for Wearable and Implantable Electronics,” Wireless Body Area Networks: Technology, Implementation, and Applications (edited by Mehmet R. Yuce and Jamil Y. Khan), ISBN 978-981-4241 -57-1. Singapore: Pan Stanford Pub., 2012.[8] W. Liu et al, “A neuro-stimulus chip with telemetry unit for retinal prosthetic device,” IEEE Journal of Solid-state Circuits, vol. 35, no. 10, October 2000.[9] MS Wegmueller et al, “Galvanic Coupling Enabling Wireless Implant Communications,” IEEE Transactions on Instrumentation and Measurement, vol. 58, no. 8, August 2009.[10] MS Wegmueller, Intra-corporeal communication for biomedical sensor networks. (Doctoral thesis). 2007. Source: http://e-collection.library.ethz.ch/eserv/eth:29911/eth-29911-02.pdf