A multi-purpose, multi-device wireless interface for bio-implants (WIBI)

We are developing a multi-purpose wireless interface system based on semistatic magnetic coupling. This interface system aims mainly to the implantable bio-sensors and actuators, and is named Wireless Interface for Bio-Implants, or WIBI. The WIBI system has two main functions: power conversion and wireless communication. Through them, a complete solution is provided to support various applications. On the other hand, it can be scaled down for specific applications to save chip area and power consumption. The WIBI system uses digital circuits extensively in circuit control and automatic tuning, which increases the flexibility and reduces the development difficulties. We successfully achieve the bi-direction full-duplex communication data rate to more than 50kbps, as well as 9 mW power transmission.; This dissertation summarizes the background and motivation of the develop185 ment of the WIBI system. Then the specific working conditions and environments of the WIBI system are discussed. According to these discussions, we determined the architecture and design requirements. The Finite Element Analysis (FEA) method is used to simulate the electromagnetical and thermal parameters in a 2-D model including the magnetic-coupled coils, the air, and the body tissue.; The next part of the dissertation focuses on the detailed design of the modules in this system. As the most essential part, the RF-DC power conversion and management is introduced first. Then the design of the receiver and the transmitter are discussed. To achieve the best communication performance, a digital phaselocked loop based on a three-fold algorithm with low power consumption is also proposed. Finally the communication protocol and the mutli-device WIBI BUS are explained. The circuits and their algorithms are verified in both simulations and experiments.