A 0.43 g Wireless Battery-Less Neural Recorder With On-Chip Microelectrode Array and Integrated Flexible Antenna.

This work presents a single-chip battery-less neural recorder with 12 on-die microelectrodes. It can be powered wirelessly up to 16 cm away from a horn antenna at 915 MHz and only consumes 104 µW dc power for accessing 10 enabled recording sites simultaneously, transmitting at 5 Mbps. The implantable device integrated with a flexible antenna weighs only 0.43 gram. In vivo measurements on an unrestricted mouse have been successfully conducted, showing response to visual stimuli.

Equation environment coupling and interference on the electric-field intrabody communication channel.

Wearable and implantable medical sensors have been investigated continuously in recent years to provide better diagnostics and monitoring for personal health care. Much attention has been drawn to the establishment of the ubiquitous body area network (BAN) to reliably connect the body sensors and collect the sensor data in real time. Electric-field intrabody communication (EF-IBC) is a promising physical link technology for the body area network. Compared to existing wireless technologies, EF-IBC fits the body characteristics better and is able to achieve higher data rate with less transmission power. EF-IBC relies on the parasitic capacitive coupling between the transmitter and the receiver to close the signal circuit loop. With this parasitic coupling, EF-IBC links can be influenced by the environment. However until now, there is lack of systematic research on various environment coupling effects to the EF-IBC channel. In this paper, environment effects on the EF-IBC channel are comprehensively studied. The interference from the nearby EF-IBC channel is investigated for the first time to gain useful insights into the establishment of the BAN with EF-IBC. The FEM model is also established to explain the mechanism of the capacitive return path.