Fig. 3: Measurement bench and transponders.
From: Wireless active feedback loop for backscattering communication
a Configuration with RF filter, b zoom on tag positioning and various foam wedges to control antenna spacing d. c Configuration without RF filter, d zoom on the tag under which a plastic film has been inserted to modify its resonant frequency \({f}_{r}\). e Metal plate used as a radar target, f dipole-shaped resonant patch, g rectangular resonant loop.
