Phased Array Fed Modified Dielectric Lens for Wide-Angle Beam-Scanning Applications

This paper proposes the design concept of the patch array-fed Luneburg lens (LL) antenna for wide-angle scanning scope coverage at 20 GHz. In the design procedure, the employed dielectric Luneburg lens should be modified firstly. After the defocusing procedure, the energy is dispersed over the lens focal area, whereby more feed elements can active simultaneously. To capture those dispersed fields, a patch array feed antenna with 19 elements is used to illuminate the modified lens. Meanwhile, this 19-element patch feed array is divided into 3 linear subarrays. After optimizing the excitation coefficients of the 19-element patch feed array, the proposed design can realized an ultra-wide scanning coverage. The achieved scanning scope is over ±80°, wherein a maximum gain of 21 dBi is obtained along the broadside direction.