A 60 kb/s-10 Mb/s Adaptive Frequency Hopping Transceiver for Interference-Resilient Body Channel Communication

An interference-resilient 60 kb/s-10 Mb/s body channel transceiver using the human body as a signal transmission medium is designed for multimedia and medical data transaction in body-area network. The body antenna effect which interferes with signals in the human body channel is examined. The body-induced interferences degrade the SIR of the signal to -22 dB in the worst case. In order to overcome the body antenna effect, a 4-channel adaptive frequency hopping scheme using the 30-120 MHz band is introduced to the body channel transceiver. A direct-switching modulator using dual frequency synthesizers and a DLL-based demodulator are proposed for 10 Mb/s FSK and the 4.2 mu s hopping time. The transceiver fabricated with 0.18 mu m CMOS withstands -28 dB SIR and its operating distance is over 1.8 in with -25 dB SIR. Its energy consumption is 0.37 nJ/b with -65 dBm sensitivity.