these components are powered
by rechargeable AA 2000-mAh Ni-MH CycleEnergy batteries
(SONY, Australia). The charge is maintained by a photovoltaic
panel MPT4.8-75 (PowerFilm Solar, Ames, IN) to achieve
full energy autonomy. The microcontroller, radio modem,
rechargeable batteries, and electronic components were encapsulated in a waterproof Polyvinyl chloride (PVC) container
(Fig. 2)