Osama M. Haraz

Dense Dielectric Patch Array Antenna With Improved Radiation Characteristics Using EBG Ground Structure and Dielectric Superstrate for Future 5G Cellular Networks

In this paper, a new dense dielectric (DD) patch array antenna prototype operating at 28 GHz for future fifth generation (5G) cellular networks is presented. This array antenna is proposed and designed with a standard printed circuit board process to be suitable for integration with radio frequency/microwave circuitry. The proposed structure employs four circular-shaped DD patch radiator antenna elements fed by a 1-to-4 Wilkinson power divider. To improve the array radiation characteristics, a ground structure based on a compact uniplanar electromagnetic bandgap unit cell has been used. The DD patch shows better radiation and total efficiencies compared with the metallic patch radiator. For further gain improvement, a dielectric layer of a superstrate is applied above the array antenna. The measured impedance bandwidth of the proposed array antenna ranges from 27 to beyond 32 GHz for a reflection coefficient (S11) of less than -10 dB. The proposed design exhibits stable radiation patterns over the whole frequency band of interest, with a total realized gain more than 16 dBi. Due to the remarkable performance of the proposed array, it can be considered as a good candidate for 5G communication applications.

Four-element dual-band printed slot antenna array for the future 5G mobile communication networks

In this article, a four-element dual-band printed slot antenna array for the future fifth generation (5G) mobile networks is proposed. The antenna element has a compact with size of 0.8 λ0 × 0.75 λ0 at 28 GHz. The simulated results show that the designed antenna has a dual-band function at 28/38 GHz that covers future 5G applications. The designed 1-to-4 modified Wilkinson power divider is used to feed the proposed array. For further enhancement of the designed power divider, an electromagnetic bandgap (EBG) structures are used. The proposed antenna array provides directional patterns, relatively flat gain, and high radiation efficiency through the frequency band excluding the rejected band.

28/38-GHz dual-band millimeter wave SIW array antenna with EBG structures for 5G applications

The design of linearly polarized dual-band substrate integrated waveguide (SIW) antenna/array operating at Ka-band is proposed. The single antenna element consists of a SIW cavity with two longitudinal slots engraved in one of the conducting planes. The longer and shorter slots are resonating at 28 GHz and 38 GHz, respectively. Only the simulated results are presented. All simulations have been carried out using industry-standard software, CST Microwave Studio. For single antenna element, an impedance bandwidth (S11 <; -10 dB) of 0.45 GHz (1.60 %) and 2.20 GHz (5.8 %) is achieved with the maximum gain of 5.2 dBi and 5.9 dBi at 28 GHz and 38 GHz, respectively. To achieve high gain, a horizontally polarized linear array of four elements (1 × 4) is designed. For the antenna array, a microstrip lines feed network is designed using 3-dB wilkinson power divider. At 28 GHz and 38 GHz, the impedance bandwidth is 0.32 GHz (1.14 %) and 1.9 GHz (5%) having maximum gain of 11.9 dBi and 11.2 dBi, respectively. A low loss/cost substrate, RT/Duroid 5880 is used in the proposed designs.

A new circularly polarized high gain DRA millimeter-wave antenna

Millimeter-Wave technology is considered as an innovative solution for the next generation of the wireless networks and for short distance data transfer between electronic devices. It allows high data transfer rates “expected to be between 40–400 faster than 802.11n wireless networks”. However, Millimeter-wave communications at frequencies around 60 GHz suffer from high propagation losses due to absorption by oxygen molecules in the atmosphere [1]. Accordingly, improving the gain is considered as one of the most important targets in antenna design for such frequencies. Also, in order to overcome multi-path, improper line-of-Sight between the transmitter and the receiver and some phasing issues due to rain or snow in the air a circular polarized antenna is required to assure high quality transmission or reception. Recently, many different types of antennas are being investigated [2]-[4] for working in mm-wave applications such as (wireless LANs, Microwave imaging and hidden objects detection). For realizing such antennas different technologies are proposed including hybrid DRA antennas [2]-[4], stacked antennas [5] and SIW antennas [6]. In this paper, we present a novel DRA/Microstrip hybrid high gain and circularly polarized antenna for MMW applications. It consists of a printed rectangular patch with a shaped corners and a hollow rectangular DR radiator works together as a single antenna element fed by a rectangular aperture in the ground plane.

New dense dielectric patch array antenna for future 5G short-range communications

In this paper, new dense dielectric (DD) patch array antenna prototype operating at 28 GHz for the future fifth generation (5G) short-range wireless communications applications is presented. This array antenna is proposed and designed with a standard printed circuit board (PCB) process to be suitable for integration with radio-frequency/microwave circuitry. The proposed structure employs four circular shaped DD patch radiator antenna elements fed by a l-to-4 Wilkinson power divider surrounded by an electromagnetic bandgap (EBG) structure. The DD patch shows better radiation and total efficiencies compared with the metallic patch radiator. For further gain improvement, a dielectric layer of a superstrate is applied above the array antenna. The calculated impedance bandwidth of proposed array antenna ranges from 27.1 GHz to 29.5 GHz for reflection coefficient (Sn) less than -1OdB. The proposed design exhibits good stable radiation patterns over the whole frequency band of interest with a total realized gain more than 16 dBi. Due to the remarkable performance of the proposed array, it can be considered as a good candidate for 5G communication applications.

Design of a 28/38 GHz dual-band printed slot antenna for the future 5G mobile communication Networks

In this article, a dual-band printed slot antenna for the future fifth generation (5G) mobile networks are proposed. The antenna is compact with size of 0.8 λ0 × 0.75 λ0 at 28 GHz. Matching between a sector-disk shaped radiating patch and the 50-Ω microstrip line is manipulated through aproximity-feed technique. An elliptically shaped aperture is etched in the ground plane to enhance the antenna bandwidth. A shunt stub is used to get more enhancement of the impedance bandwidth of the antenna. To reduce the interference between the 5G system and other systems, π-shaped slot is etched off in the feed line to create a notched band of 30-34 GHz. The simulated results show that the designed antenna has a dual band function at 28/38 GHz that covers future 5G applications. The proposed antenna provides almost omni-directional patterns, relatively flat gain, and high radiation efficiency through the frequency band excluding the rejected band.

UWB Antennas for Wireless Applications

Currently, there is an increased interest in ultra-wideband (UWB) technology for use in sev‐ eral present and future applications. UWB technology received a major boost especially in 2002 since the US Federal Communication Commission (FCC) permitted the authorization of using the unlicensed frequency band starting from 3.1 to 10.6 GHz for commercial com‐ munication applications [1]. Although existing third-generation (3G) communication tech‐ nology can provide us with many wide services such as fast internet access, video telephony, enhanced video/music download as well as digital voice services, UWB –as a new technology– is very promising for many reasons. The FCC allocated an absolute band‐ width up to 7.5 GHz which is about 110% fractional bandwidth of the center frequency. This large bandwidth spectrum is available for high data rate communi-cations as well as radar and safety applications to operate in. The UWB technology has another advantage from the power consumption point of view. Due to spreading the ener-gy of the UWB signals over a large frequency band, the maximum power available to the antenna –as part of UWB sys‐ tem– will be as small as in order of 0.5mW according to the FCC spectral mask. This power is considered to be a small value and it is actually very close to the noise floor compared to what is currently used in different radio communica-tion systems [2].

B2. Broadband millimeter-wave rectangular reflectarray antenna utilizing novel polarization insensitive multi-resonant unit cells

A new broadband millimeter-wave reflectarray antenna structure utilizing novel polarization insensitive multi resonant unit cells is proposed. The design frequency of the RA is set at 30 GHz, and it consists of 20×20 polarization independent insensitive resonant unit cells (UCs), which are illuminated by pyramidal horn antenna. The unit cell of this array contains two concentric rings combined with a cross loop and cross strips inside for bandwidth enhancement. For maximum aperture efficiency and realized gain, a pyramidal horn antenna placed at F to obtain F/D=0.4. The simulation results show that the obtained maximum gain is 23.8 dB with a slight variation over the operating frequency range and a good cross-polarization level.

A millimeter-wave circular reflectarray antenna for future 5G cellular networks

A new broadband millimetre-wave reflectarray antenna structure utilizing novel polarization insensitive multi resonant unit cells is proposed. The design frequency of the RA is set at 30 GHz, and it consists of 20×20 polarization independent insensitive resonant unit cells (UCs), which are illuminated by pyramidal horn antenna. The unit cell of this array contains two concentric rings combined with a cross loop and cross strips inside for bandwidth enhancement. For maximum aperture efficiency and realized gain, a pyramidal horn antenna placed at F to obtain F/D=0.4. The simulation results show that the obtained maximum gain is 25.1 dB with a slight variation over the operating frequency range and a good cross-polarization level.

Study the Effect of Using Low-Cost Dielectric Lenses with Printed Log-Periodic Dipole Antennas for Millimeter-Wave Applications

Design of V-band high-gain printed log periodic dipole array (PLPDA) antenna loaded with a low-cost spherical dielectric lens is introduced. The proposed antenna consists of microstrip-line-fed log-periodic dipole antenna designed to operate in the V-band with a peak gain of 12.64 dBi at 60 GHz. To enhance the antenna gain, a dielectric lens is installed. The antenna prototype is fabricated and then tested experimentally using Agilent E8364B PNA Network Analyzer. Experimental results agree well with the simulated ones. The simulated results show that the proposed antenna can work from 42 GHz up to 82 GHz with a fractional impedance bandwidth of 64.5% covering the whole V-band (50–75 GHz). At 60 GHz, the proposed antenna has peak gain of 26.79 dBi with a gain variation of 3.5 dBi across the whole V-band with stable radiation patterns over the operating band. The proposed PLPDA antenna achieves good side-lobe suppression, excellent front-to-back ratio in both E- and H-planes, and low cross-polarization levels over the entire frequency range. These unique features will make this antenna suitable for different interesting applications such as millimeter-wave radar and imaging applications.