Broadband and 28/38-GHz Dual-Band Printed Monopole/Elliptical Slot Ring Antennas for the Future 5G Cellular Communications

The mobile industry has seen significant growth; it evolved from analog to digital second generation (2G) Global System for Mobile (GSM), then to high-data rate cellular wireless communication such as third generation (3G) Wideband Code Division Multiple Access (WCDMA), and further to packet optimized 3.5G High Speed Packet Access (HSPA) and fourth generation (4G) Long-Term Evolution (LTE) and LTE advanced systems [1]. The 4G wireless communication systems have been deployed in many countries. However, with the widespread use of wireless devices and mobile services, there are still some challenges that cannot be absorbed until the 4G, such as the spectrum crisis and high-energy consumption [2]. The race to search for innovative solutions to enable the fifth generation (5G) wireless communication networks era has begun. Once developed, the 5G network will permit gigabitper-second transmission on compatible mobile devices. 5G is expected to meet the requirements to enable higher capacity, higher rate, more connectivity, higher reliability, lower latency, greater versatility, and application domain-specific topologies. New concepts and design approaches are in dire need. Future 5G will most likely use millimeter-wave frequencies. Beamforming could be one of the solutions for the future 5G cellular communications. Theoretical feasibility and prototype results for millimeter-wave (mmWave) beamforming as an enabling technology for 5G cellular communications have been discussed in [3]. Achieving higher data rates with mmWave beamforming for next generation communications is proposed in [4]. Author has contributed in designing several slot/monopole antenna designs for ultrawideband (UWB) applications [5–15]. Different monopole antenna shapes with ultra-wide bandwidth have been proposed in [5–7]. An elliptical slot antenna with elliptical shaped microstrip-line fed radiator for UWB operation has been introduced in [5]. Another monopole antenna with a trapezoidal shaped patch with two elliptical shaped cuts from its edge forming a J Infrared Milli Terahz Waves (2016) 37:308–317 DOI 10.1007/s10762-016-0252-2