Investigation of relationship between SAR and required communication performance for wireless capsule endoscope

In this paper, we investigate local peak specific absorption rate (SAR) based on required communication performance for a wireless capsule endoscope at 400 MHz medical implant communication service (MICS) band. First, in order to calculate the bit error rate (BER) performance under this implant propagation channel and derive the required transmit power to secure a permissible BER, we perform finite-difference time-domain (FDTD) simulations for implant body area network (BAN) channel modeling with two numerical human body models. Secondly, we calculate the local peak SAR under the required transmit power when the implant transmitter moves along the digestive organs. Based on such an approach, we attempt to determine a threshold transmit power which could be used to ensure the induced SAR not exceeding the safety guideline in the human body.