A full-duplex wireless integrated transceiver for implant-to-air data communications

This paper presents a novel fully integrated full-duplex data transceiver to support bidirectional high-data rate neural interfaces (electrical stimulation and neural recording). The transmitter (TX) and the receiver (RX) are designed to share a single implantable antenna. The TX generates IR-UWB based on edge combining, and the RX uses a novel ISM-2.4-GHz narrow-band OOK receiver. Separation between the TX and RX path is implemented by: 1) properly shaping the transmitted pulse, so its spectrum falls between 3.1 and 7 GHz UWB subband, and 2) carefully filtering the spectrum of the received waveform directly in the receiver low-noise amplifier (LNA), to avoid using a circulator or a diplexer (found in most full duplex systems). The receiver is designed to support downlink telemetry of neural stimulation applications with a data rate as high as 100 Mbps within a power budget of 5 mW. The transmitter is designed to support uplink back telemetry of neural recording applications with a data rate of up to 500 Mbps for power consumption of 5.4 mW and 10.8 mW for OOK and BPSK modulations, respectively (10.8 pJ/b). Measurement results obtained with biological tissues confirm full functionality of the fabricated full duplex transceiver. The total size of the chip is 0.8 mm².