**6. Conclusions**

Because of the requirement of medical test for GI tract, WCE came to the world. It solves many restrictions on exploring GI tract. With the development from 2001, WCE has become a promising device with suitable requirement. It has image sensor and lighting, control unit, wireless communication unit, power source, and mechanical actuator. The system can be operated outside the human body, the size of the capsule endoscope system is smaller, and the interconnection between devices was optimized, power consumption also reduced with technology optimized. Some companies and individual are still studying on new functions and optimization.

For wireless capsule endoscopy antenna, several basic standards and situation of operation in human body were discussed. The signal transmission efficiency of the antenna will directly decide the quality of the received real-images and rate of power consumption. Because of the lossy material absorbs a number of waves and decreasing the power of receiving signal, human body presenting strong negative effects on the microwave propagation. Wireless capsule endoscopy transmitting antenna is for sending out the detected signal inside human body and receiving antenna receive the signal outside human body. Several transmitting antennas are introduced in this article. The two fundamental types of transmitting antenna are the spiral antennas and conformal antennas both feature as the small physical size, relatively large bandwidth, omni-directional pattern and polarization diversity. The receiving antennas operating outside of human body are also discussed, such as the narrow bandwidth antenna for receiver, microstrip meandered planar antenna and the receiver antenna with buffer layer. All of them operate well outside the human body.
