This paper presents a systematic parameter study on mesh pattern for optically transparent flexible antenna with feedline. In implementing a transparent flexible antenna using a metal mesh, transparency and performance of antenna and feedline are opposite factors. To understand how both elements are affected by the design parameters of the mesh, we analyze the performance of the feedlines and antennas according to the design parameters of diamond and square meshes. Moreover, the effect of the difference in the shape of diamond mesh and square mesh on performance is analyzed. The measured results of the fabricated samples offer the feasibility of implementing transparent feedlines and antennas with similar performance to nontransparent feedlines and antennas.

In this paper, we designed a flexible antenna operating in the WLAN/C-band/X-band and analyzed the antenna bending characteristics. It is advantageous to have a wide bandwidth because the resonant frequency of the flexible antenna can be changed when it is bent. The proposed antenna was designed based on a ring monopole antenna with broadband characteristics. Slots and t-strip lines to the ring, stubs to the feed, and stepped structures to the ground plane were added to increase bandwidth. As a result of analyzing the characteristics of the proposed antenna when bent through the S-parameter, it was confirmed that the proposed antenna is suitable at the target frequency, even if it is bent. The size of the antenna is 0.256 λ × 0.32 λ × 0.0016 λ () at 2.4 GHz, and the antenna bandwidth is 15.68% (2.36 GHz~2.87 GHz) at 2.615 GHz and 111.69% (3.4 GHz~12 GHz) at 7.7 GHz.