A Compact 38 GHz Multibeam Antenna Array With Multifolded Butler Matrix for 5G Applications

• Published in: IEEE antennas and wireless propagation letters Vol. 16; pp. 2996 - 2999
• Main Authors: Yue Cao, Kuo-Sheng Chin, Wenquan Che, Wanchen Yang, Li, Eric S.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.01.2017; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antenna arrays; Antenna measurements; Beamforming; Beams (radiation); Butler matrices; Butler matrix; Couplings; fifth-generation (5G) application; multibeam antenna; Phase shifters; Radiators; Size reduction; substrate integrated waveguide (SIW); Substrates
• ISSN: 1536-1225; 1548-5757
• DOI: 10.1109/LAWP.2017.2757045

A compact 38 GHz multibeam antenna array is presented for fifth-generation applications. A beamforming network featuring a substrate integrated waveguide (SIW) multifolded 4 × 8 Butler matrix is constructed. Benefiting from multilayer structure, the Butler matrix is highly integrated and assembled underneath the radiators to achieve compactness. The Butler matrix is, then, combined with an 8 × 10 SIW slot-coupled patch array to establish four steering beams along the H-plane and to accomplish size reduction of 53.5% in its longitudinal direction. For demonstration, one prototype of the proposed antenna array was fabricated. The measured four beams point toward ±36° and ±12° with gains equal to 19.8 and 21 dBi, respectively.