A lMb/s, −75dBm sensitive fully integrated body channel transceiver for a low energy compact wearable healthcare sensor

A 1Mb/s fully integrated FSK transceiver using human body as a transmission medium is presented for a low energy compact wearable healthcare sensor. 20-40MHz, which is divided into 4 sub-channels, is utilized for body channel communication (BCC) to tolerate body induced interferences. FSK transmitter (TX) adopts 8b digitally controlled LC oscillator for replacing power consuming PLLs to achieve fast switching radio within 1μβ. The direct conversion receiver (RX) guarantees the operation at -75dBm unstable FSK spectrum received through body, and provides BER less than 10
^-6
without the help of bulky external X-tal oscillator. The proposed transceiver of 2.1mm × 3.3mm was fabricated in 0.18μm CMOS process, and dissipates 2.3mW/3.1mW in TX and RX, respectively.