Design of 38 GHz Parallel Plate Lens Beam-forming Network and Application of Phase Array Antennas

• Main Authors: Ying-Shan Chen, 陳瑩珊
• Other Authors: Yao-Chiang Kan
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/75448864188543837664

碩士 === 元智大學 === 通訊工程學系 === 105 === With the advent of the 5th generation of mobile communications, designs for antennas and circuits have been shifted to higher frequency bands. Substrate integrated waveguide (SIW) has been widely used recently because it has the advantages of traditional planar transmission lines and metallic waveguide. In this paper, a new type of planar beam-forming network has been studied and improved. A parabolic reflector is realized on the substrate via the technique of SIW, which can be used in both single-input to multi-output and multi-input to multi-output situations, and configurable beams can be generated by the connected array antenna. Firstly, a corrugated structure added on the linear reflecting surface of the beam-forming network is proposed to minimized the interferences from multi path, and then is the comparison with the original structure. Results from the simulations and measurements show that the corrugated structure can achieve a more focus energy distribution, with a phase difference lower than 10 degrees. Furthermore, because the severe losses of the electromagnetic wave propagation in the dielectric structure in mmW band, the dielectric substrate is hollowed out in this study in order to reduce the losses. It is shown in the simulation results that a loss lesser than 3 dB is accomplished. Also, a double layer coupling structure is used to calibrate the phases and to amend the beam shift caused by multi feeds. Then, an 8X10 serial microstrip antenna array operating at 38 GHz is proposed in this thesis, which its gain can achieve 22.58 dB. By using different combinations of phase distributions, a ±15o beam shift can be attained. The characteristic of the lens beamforming network has been verified through the proposed antenna array. By the verification of the measurement results, this new structure can reach good radiation characteristic, and can be used in the development of mmW applications.