Conformal Array Antenna for Applications in Wide-Scanning Phased Array Antenna Systems

A dipole with four branches, fed by Marchand balun, is designed to be conformal with wing of an unmanned aerial vehicle. With the help of branches, the proposed dipole element achieves a better impedance matching performance. Meanwhile, the metallic coupled strip is added to move the scanning blindness out of the operating frequency band, without deterioration at broadside radiation. Besides, the beamwidth in the vertical plane, i.e., the H-plane of the dipole, can be effectively compressed by loading three metallic strip directors, and the element gain increases as well. Based on the dipole element, a 12-element linear phased array is designed and simulated. The simulated results show that the array achieves ±60° scanning range in the horizontal plane, with the voltage standing wave ratio lower than 2.5 in the operating band of 2.4∼3 GHz. Moreover, the 3 dB beamwidth in the H-plane is 81° at the center frequency of 2.7 GHz. The measured results of the fabricated antenna prototype agree reasonably well with the simulated ones, which verify the feasibility of the wing-conformal linear phased array design.