Synthesis of multi‐polarised upside conical frustum array antenna for 5G mm‐Wave base station at 28/38 GHz

Abstract

In this study, a multi‐polarised millimetre‐wave (mm‐Wave) base station operating at 28/38 GHz is introduced for future fifth generation (5G) mobile communication networks. The proposed station employs 32‐element array antenna distributed in upside conical frustum configuration (UCFC) to synthesise multi‐beam patterns adopting directivity and polarisation control. First, the design of dual‐band circularly polarised antenna element at 28/38 GHz is discussed. The measured results show that the designed antenna element has a reflection coefficient less than −23 dB with a realised antenna gain of 8 dBi, on average, in the assigned frequency bands. Based on the designed antenna element, the antenna array performance is studied in terms of gain, radiation efficiency, reflection coefficient, and coverage efficiency. The results are compared with those obtained from 32‐element structured in an octagonal prism configuration (OPC). For antenna design parameters and multi‐beam pattern synthesis, a modified version of hybrid gravitational search algorithm and particle swarm optimisation is proposed. It is found that, the introduced UCFC outperformed the OPC by 19.8%. Moreover, distributing the antenna array in UCFC improved the convergence by 21.7% compared to OPC.

Metasurface-Based Single-Layer Wideband Circularly Polarized MIMO Antenna for 5G Millimeter-Wave Systems

“…The antennas reported in [34][35][36] offer the advantages of a single printed layer and CP radiations but have the disadvantages of limited AR bandwidths and the absence of MIMO functionality as well as low gain even though these designs are at microwave frequencies. It is worth mentioning that among the 5G antennas with MIMO capabilities [44][45][46][47][48][49][50][51], only [48][49][50] have CP polarization. The antennas with superstrate [48][49] offer the advantages of MIMO, wide bandwidth, and high gain (<14 dBic) have the critical disadvantages of design complexity because of the multiple printed layers and the presence of air gap.…”

“…The antennas with superstrate [48][49] offer the advantages of MIMO, wide bandwidth, and high gain (<14 dBic) have the critical disadvantages of design complexity because of the multiple printed layers and the presence of air gap. The CP MIMO antenna presented in [50], has a low gain of 8 dBic while the CP bandwidth is restricted to only 3%. The 5G CP antennas presented in [26,[51][52][53][54] are missing MIMO features besides of limited operating bandwidths.…”

“…Additionally, CP antennas also offer immunity against prominent propagation losses, interferences, and multi-path distortions in mm-wave frequencies. It is evident from the literature review that a few works have been done in the design of CP MIMO antennas at the designated 5G frequency bands [48][49][50]. This is simply because of the design and realization challenges that are associated with the much smaller (few millimeters) physical size of the antenna.…”

“…Also, the multiple layered substrates/FSS (frequency selective surfaces) causes difficulty in the design realization and are not suitable for mass production for practical applications. A dual-band CP MIMO antenna with twelve ports for the 5G base stations is proposed in [50]. The antenna system provides both LP and CP radiations based on end-user requirements and the single-element antenna has a gain of 8 dBic with an AR bandwidth of only 3% (27.5 -28.5 GHz).…”

Design of Compact mm-wave Tunable Filtenna Using Capacitor Loaded Trapezoid Slots in Ground Plane for 5G Router Applications

“…To deeply investigate the performance of the mm-wave 5G router, the total scan pattern and coverage efficiency are studied [25], [26]. Whereas, the total scan pattern can be obtained easily by extracting the best attainable gain at every point (θ, ϕ) from all array patterns corresponding to the electronically steered beams at different feeding phases.…”