Location System for Micro Medical Device inside Human Body Based on Packet Error Rate Analysis of ZigBee

For determine the location of the ingestible electronic pill inside the human body ，a new positioning system of the micro medical device inside the human body is designed. CC2430 communication chips combined with ZigBee protocol software are used as radio frequency transceiver of the system. When transmission power is very low, significant error codes will be generated at the receiving terminal. We can locate the electronic pill according to the analysis results of the packet error rate. And we adopt Trilateration to build up a set of nonlinear equations, which is related to the inter-node distance and spatial location variables of the pill. At last, equations are solved with numerical solution. It is found that the method is feasible.