A differential miniature transponder for 9.4/18.8 GHz harmonic bee searching radar with low gain degradation from bee's body

A new 9.4/18.8 GHz harmonic radar transponder for the bee searching radar is proposed. The proposed transponder reduces the degradation of the conversion rate from the loss of the bee's body effect and promotes the antenna gain. It is designed in the way of differential operation with two resonate frequency at 9.4 and 18.8 GHz. It also has a smaller size which can be mounted on bees. The omnidirectional gain in E-plane is above 0 dB and the degradation of the conversion rate from the loss of the bee's body effect is 3–4 dB. This improvement is helpful to extend the detection range of the bee searching radar.