This letter proposes a rotated stacked Yagi antenna with high directivity and circular polarization. The proposed antenna consists of three elements with a rotation angle and different lengths: a director, a reflector, and a driven element connected to the coaxial feeder. Each stacked element with different lengths is equally rotated at an angle of 60° with respect to the lower element so that the dipole array antenna forms a high directive circular polarization.

[A…

 A quadruple-polarization reconfigurable feeding network for an unmanned aerial vehicle (UAV) RF sensing antenna operating at 915 MHz is presented. It consists of one single-pole four-throw (SP4T) switch, one 90◦ hybrid coupler, two 180◦ hybrid couplers, and two single-pole double-throw (SPDT) switches. By controlling the SP4T and SPDT switches, quadruple polarizations with two linear polarizations (vertical and horizontal) and two circular polarizations (right-hand and left-hand) …

​ This letter presents a printed fan-shaped meandered dipole antenna with mutual-coupled dual resonance for enhancing impedance bandwidth in a compact antenna size. The proposed antenna consists of a printed dipole antenna mutually coupled to an antenna parasitic element of a different size for dual resonance and microstrip feeding. 

[Antenna Specification] 

Freq. band : 920 MHz

Impedance BW : 12%

Peak gain : 3.2 dBi

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