Design and analysis of conformal base station antenna for 5G applications

Conformal array antenna is well adopted to be installed on the surface of high speed aircraft or other mobile platform carriers. Conformal array antenna not only does not change the dynamic performance of the carrier, but it is easy to install. In practice, conformal array has occlusion effect. That is, some array elements cannot receive the incident signal from a given direction. In this study, uniform cylindrical conformal antenna array is studied for 5G applications, and good simulation results are obtained. The main work contents are as follows: Firstly, the theory of the linear array antenna is introduced. Both planar array antennas and circular array antennas are discussed. The cylindrical conformal antenna can be viewed as a circular array stacked together. A comparison between planar, circular and cylindrical arrays are provided. Then, the patch antenna conformal to the cylinder surface is designed using a commercial sofware, namely Microwave Studio by Computer Simuation Technology. The antenna elements are uniformly distributed on the surface of the cylindrical structure medium, and discrete ports are used to connect each patch antenna to a metal ground on the back of the substrate. The outer radius of the cylinder is 63.7mm and the inner radius of the cylinder is 62 mm and the height is 150 mm. The radiation pattern generated by 1x16 rectangular identical patches fed with the same signal is numerically calculated and compared with the theoretical value. Finally, in this thesis, the beam scanning performances of the antenna array is analyzed: multi-port excitation is performed and beam synthesis is carried out applying weighted feeding coefficients computed by a Matlab script. Comparison between ideal array, consisting of isotropic radiators, and directive radiators (patches) is presented and discussed.