A 3-D-Printed Deployable Luneburg Lens Antenna Based on the Pop-Up Kirigami Sphere

A $\text{K}_{\mathrm {u}}$ -band deployable fully dielectric Luneburg lens antenna based on the pop-up kirigami sphere is presented in this article. The implementation method is that the proposed Luneburg lens is discretized into multiple concentric spherical shells and each shell is subpartitioned by two orthogonal rows of parallel loops. Flexible joints are employed at all the intersections of the orthogonal loops to accomplish the deployability of the proposed Luneburg lens. The 3-D printing technology of multijet printing (MJP) and the computer numerical control machining technology are adopted to, respectively, fabricate the prototype of the lens and that of the horn antenna for feeding. The measured results reveal that the proposed antenna has good impedance matching levels within the $\text{K}_{\mathrm {u}}$ band and gains of around 14.7–18.6 dBi with the corresponding aperture efficiencies between 37.2% and 69.9%. Narrow beamwidths and symmetric radiation patterns can be seen in the E-plane and the H-plane. The proposed Luneburg lens can be transformed into the folded status, significantly reducing its profile and volume for easier transportation and storage. The deployable Luneburg lens is presented for the first time to the best of our knowledge and could well be a promising approach for the high-performance full-size Luneburg lens antennas to be utilized in a wider range of application scenarios.