BodyWire: A 6.3-pJ/b 30-Mb/s −30-dB SIR-Tolerant Broadband Interference-Robust Human Body Communication Transceiver Using Time Domain Interference Rejection

Abstract

Human body communication (HBC) utilizes the human body as the communication medium between devices in and around the body, providing an energy-efficient, secure alternative to radio wave communication traditionally used in body area networks (BAN). However, the human antenna effect results in the human body picking up environmental interference affecting HBC transmissions. Most state-of-the-art HBC transceivers utilize narrowband modulation techniques to communicate using frequencies, which are not affected by interference. In this article, we use capacitive termination and voltage mode communication techniques to utilize the human body as a broadband (BB) communication channel enabling as a BB HBC. An integrating dual data rate (I-DDR) receiver utilizing time-domain interference rejection (TD-IR) through integration and periodic sampling is used for interference-robust BB HBC operation. The proposed receiver can achieve higher energy efficiency as it utilizes the full bandwidth of the body for data transmission and does not require any modulation/demodulation. The BB HBC transceiver is fabricated in the TSMC 65-nm technology. Measurement results show 6.3-pJ/bit energy efficiency at a data rate of 30 Mb/s with -30-dB signal-to-interference ratio (SIR) tolerance, making it 18× energy efficient compared with state-of-the-art HBC transceivers.