Design and implementation of intrabody communication hub/alarm unit in IBC platform for fall prevention system

Abstract

We report a high-performance intrabody communication (IBC) hub/alarm unit in IBC platform for fall prevention system. The IBC hub/alarm unit consists of a binary frequency shift keying (BFSK) receiver, an on-off keying (OOK) transmitter, an audio digital-to-analog converter (DAC), an audio power amplifier (PA), and a microcontrol unit (MCU). The BFSK receiver receives the biomedical signals from the IBC sensor node biomedical system-on-a-chips (SOC) through human body, and then transmits them to PDA/cell phone or earphone alarm terminal through the MCU. The OOK transmitter takes commands from PDA/cell phone, and then transmits them to the IBC sensor node biomedical SOC through human body. The audio DAC and PA send an alarm message to the earphone in case of anomaly based on the biomedical signals received by the BFSK receiver. Such kind of transmission methodology in conjunction with our proposed IBC platform is much more power-efficient than wireless communication. Moreover, since no antenna is required, small chip size is achieved. At supply voltage of 0.7 V, the BFSK receiver consumes 520 μW (0.17 nJ/b) and achieves sensitivity of -80 dBm at data rate of 3 Mbps, better than previous work in the literature. The excellent results indicate the IBC hub/alarm unit is suitable for IBC platform for fall prevention system. © 2014 Wiley Periodicals, Inc.