A closed-loop wireless homecage for optogenetic stimulation experiments

This paper presents a smart EnerCage-homecage (HC) system for optogenetic stimulation, equipped with magnetic resonance based wireless power transmission (WPT), closed-loop power control, and data communication via Bluetooth Low Energy (BLE). The proposed system is encompassed with four rectangular slanted overlapping high-Q resonators and a wire-wound driver coil, all tuned at 13.56 MHz. An optical headstage is implemented capable of driving 4 micro light-emitting diodes (μ-LEDs) based on stimulation commands received via the BLE link on-the-fly, while being wirelessly powered in a closed-loop fashion. Measurements show that the entire headstage unit was provided with up to 51 mW throughout the homecage up to the maximum elevation of 10 cm, while the transmitter (Tx) power consumption changed from 1.5 W to 2.1 W (overall η, 2.4-3.4%).