  Ambient backscatter communication technology (AmBC) and a novel device
category called zero-energy devices (ZED) have recently emerged as potential
components for the forthcoming 6th generation (6G) networks. A ZED communicates
with a smartphone without emitting additional radio waves, by backscattering
ambient waves from base stations. Thanks to its very low consumption, a ZED
powers itself by harvesting ambient light energy. However, the time variations
of data traffic in cellular networks prevents AmBC to work properly. Recent
works have demonstrated experimentally that a backscatter device could be
detected by listening only ambient pilot signals (which are steady) instead of
the whole ambient signal (which is bursty) of 4G. However, these experiments
were run with a 4G base station emulator and a bulky energy greedy backscatter
device. In this paper, for the first time, we demonstrate real-time AmBC on the
field, with Orange commercial 4G network as ambient source and Orange
Zero-Energy Device.
