A capsule endoscope transmits images of the digestive organs from the inside to the outside of the body. For in-to-out body transmission, a capsule endoscope can use human body communication (HBC) instead of radio frequency (RF). However, an HBC endoscope does not transmit in the opposite direction (i.e., out-to-in body transmission). In this study, out-to-in body transmission using HBC at 13.56 MHz was investigated, and the results are presented herein. The coexistence between the 13.56-MHz out-to-in body transmission and HBC was investigated through channel measurement and bit error rate (BER) analysis. The use of 13.56 MHz is advantageous because out-to-in body transmission can be easily implemented using various existing chip solutions that have been developed for 13.56-MHz radio-frequency identification (RFID).

中文翻译：

---

胶囊内窥镜13.56MHz体外信道及其与人体通信共存的研究

胶囊内窥镜将消化器官的图像从体内传输到体外。对于体内外传输，胶囊内窥镜可以使用人体通信 (HBC) 代替射频 (RF)。然而，HBC 内窥镜不会以相反的方向传输（即，由外向内传输）。在这项研究中，研究了在 13.56 MHz 下使用 HBC 进行的由外到内的身体传输，并在此提供了结果。通过信道测量和误码率 (BER) 分析研究了 13.56 MHz 体外传输和 HBC 之间的共存情况。使用 13.56 MHz 是有利的，因为可以使用为 13.56 MHz 射频识别 (RFID) 开发的各种现有芯片解决方案轻松实现体外传输。