A Light Weight Transponder for Bee Searching Harmonic Radar

This paper demonstrates a new transponder for a 9.4/18.8 bee searching harmonic radar. The transponder is designed for light weight so as to mount on a bee more easily. A FPC soft board is used to reduce the weight and the half folded architecture is employed to decrease the loss from the bee's body. The transponder has a weight of 11 mg and better than -18 dB conversion gain with the power density of 5W/m $^2$.Several field experiments were performed and each bee can fly normally while carrying a transponder.