STDES-BFTAG01

描述

The STDES-BFTAG01 is an energy autonomous and battery-free wireless sensor.

The companion STPVTAG app is available for free download on Google Play.

The device implements off-the-shelf components (2 x 2~cm PCB, 4 mm thickness, weight <5 grams).

It features Bluetooth low energy (BLE) communication and can harvest and sense indoor ambient light with a limit of detection of 200~lux.

The board is energetically autonomous thanks to a photovoltaic transducer that simultaneously provides power and light sensing functionality, together with time domain read-out.

The number of tag transmissions to a remote base station, in a given time interval, proportionally varies in relation with light intensity, that is, more light is equal to more frequent broadcasts.

Therefore, the battery-free tag expresses light intensity as a function of time and this phenomenon can be exploited by the base station to convert transmission intervals into accurate expressions of light intensity.

The same concept can be extended to other sources of ambient energy, such as kinetics, thermal, etc.