As part of the R&D announcement during Sigfox Connect 2018 a passive Sigfox tag has been introduced. I’ve seen the demo made by Christophe Fourtet and the technology is really promising.
Basically a passive tag is a tag with no battery. The one actually seen it really near to be a passive tag. This tag is receiving power from a radio signal and with this power respond with a radio message. In the Sigfox context this radio message is a Sigfox message. What is really strong with this technology is the low level of power to be provided to get it working. I’ve seen it working with less than a watt and a distance larger than 10 meters with not any radio optimization on the prototypes. The radio message, thanks to the Sigfox communication technology can reach a distant basestation getting benefit of the large Sigfox radio range. The use in conjunction of a micro-gateway sounds a good idea. The global solution looks to be a low cost and easy to deploy solution for asset management & tracking.