Dual-band Transceiver with Mutually-coupled On-chip Antennas for Implantable/Wearable Devices

This paper presents a fully integrated dual-band transceiver (TRX) with mutually-coupled on-chip antennas for implantable and wearable devices. It operates at 915 MHz and 2.4 GHz in both transmit and receive modes to enable bidirectional communication between medical and consumer electronics using a single chip. The TRX is fabricated in 180 nm CMOS along with a power management unit (PMU) with a size of 2.4x 1.9 mm(2). The PMU generates the required supplies to power the internal TRX, external sensors, and controller units from a single battery. The transmitter (TX) consists of a mutuallycoupled dual-band oscillator and uses the on-chip antennas as the inductors of the oscillators. The maximum uplink data rates of the TXs are 20 Mb/s and 40 Mb/s for 915 MHz and 2.4 GHz, respectively, with corresponding TX efficiencies of 62 pJ/b and 35 pJ/b. The maximum achievable downlink data rates are 2 Mb/s and 1 Mb/s for 915 MHz and 2.4 GHz, respectively, resulting in 2 pJ/b and 4 pJ/b of energy efficiencies. Importantly, the proposed TRX achieves uplink and downlink communication ranges of 30 cm and 17 cm for the 915 MHz band, and of 38 cm and 2 cm for the 2.4 GHz band, respectively.