Design and Experimental Validation of Miniaturized Self-Triplexing Antenna Employing HMSIW

The design and experimental verification of miniaturized cavity-backed self-triplexing antenna (STA) with high-isolation employing half-mode substrate integrated waveguide (HMSIW) are presented in this work. The proposed STA is constructed by using HMSIW, an Y-shaped slot and three 50Ω feed lines. Three unequal radiating patches are generated by engraving an Y-shaped slot on the top surface of the HMSIW cavity to operate at 3.7/5.0/5.8 GHz for WiMAX/WLAN applications. The proposed STA allows to realize one of the operating band independently by keeping other operating band unaltered and vice-versa. The circuit area of STA is highly miniaturized due to the use of HMSIW cavity and loading of Y-shaped slot. The isolations between three ports are greater than 31 dB. The fabricated STA provides 5.5, 5.92 and 5.93 dBi peak gains at 3.7, 5.0 and 5.8 GHz, respectively. The efficiency of the STA is greater than 92% at all the frequency bands. The constructed STA has a front-to-back ratio of more than 23 dB and a separation of more than 21 dB between co-to-cross polarization levels. Fabrication and measurement are used to validate the intended STA.

Circularly polarized CPW fed MIMO/Diversity antenna for Wi-Fi and WLAN applications

In this paper, circular polarized two-element and eight-element CPW fed MIMO/Diversity antenna with defected ground is presented. The dimension of the two-port antenna is 30 mm × 30 mm whereas the edge-to-edge gap between radiating elements is 5.65 mm. The |S11| in dB varies from 4.95 to 5.95 GHz with a gain up to 4.1 dB and efficiency is more than 90%. The isolation of two-element CPW antenna is more than 20 dB with open and diagonal stub in the ground whereas more than 18.7 dB for eight-element antenna without decoupling network. The circular and rectangular stub perturbs the surface current in the ground and is responsible for RHCP and LHCP in two-elements and eight-elements antenna where it covers the complete operating band. The acceptable ECC, TARC, DG, and CCL values of the antenna are determined which represents the diversity characteristics of the antenna. The Wi-Fi/WLAN applications can be fulfilled with the proposed two and eight-element antenna.

A Pentaband Compound Reconfigurable Antenna for 5G and Multi-Standard Sub-6GHz Wireless Applications

This work proposes a low-profile, printed antenna that offers pattern and frequency reconfiguration functionalities printed on FR-4 substrate with a size of 46 × 32 × 1.6 mm3. The proposed antenna can operate in five different frequency bands, each one identified as a Mode, wherein there are possibilities of pattern reconfiguration. The frequency and pattern reconfigurability are made possible through 12 p-i-n diode switches (S1 to S12). The former is enabled through the switches S1 to S4 within the radiating patch, hence effectively controlling the resonant bands of the antenna; the latter is made possible through main lobe beam steering, enabled by the rest of the eight switches (S5 to S12), loaded in split parasitic elements designed on both sides of the radiator. The proposed antenna operates in the 5 GHz (4.52–5.39 GHz) band when all switches are OFF. When S1 is ON, the operating band shifts to 3.5 GHz (2.96–4.17 GHz); it changes to a 2.6 GHz (2.36–2.95 GHz) band when S1 and S2 are ON. When S3 is also turned ON, the antenna shifts to the 2.1 GHz Band (1.95–2.30 GHz). When S1–S4 are ON, the operating band shifts to a 1.8GHz (1.67–1.90 GHz) band. In all these bands, the return loss remains less than −10 dB while maintaining good impedance matching. At each operating band, the ON/OFF states of the eight p-i-n diode switches (S5 through S12) enable beam steering. The proposed antenna can direct the main beam in five distinct directions at 3.5GHz, 2.6 GHz, and 2.1 GHz bands, and three different directions at 5 GHz and 1.8 GHz bands. Different 5G bands (2.1, 2.6, 3.5, and 5) GHz, which fall in the sub 6GHz range, are supported by the proposed antenna. In addition, GSM (1.8 GHz), UMTS (2.1 GHz), 4G-LTE (2.1 GHz and 2.6 GHz), WiMAX (2.6 GHz and 3.5 GHz) and WLAN (5 GHz) applications are also supported by the proposed antenna, which is a candidate for handheld 5G/4G/3G devices.

Gain Enhancement Planar Lens Antenna based on Wideband Focusing Gradient Meta-surface

A three-layered transmitting focusing gradient meta-surface (FGMS) has been proposed, which can achieve broadband gain enhancement from 8.2 GHz to 10 GHz. The element of broadband transmitting FGMS has high transmitting efficiencies that over 0.7 and achieve [0, 2π] phase range with a flat and linear trend in the operating band. The FGMS can transform the spherical waves into plane waves. Three patch antennas working at 8.2 GHz, 9.1 GHz, and 10 GHz respectively are placed the focus of broadband FGMS as the spherical-wave source to build a broadband planar lens antenna system. It achieves a simulation gain of 15.44 dBi which is 7.51dB higher than that of the bare patch antenna at 10 GHz with satisfying SLLs and beamwidths. However, it enhanced the gain of the bare patch antenna in a wide operating band. Finally, the FGMS and the patch antenna are fabricated and measured. The measured results are in good agreement with the simulations.

Design of Two Element Triple Band MIMO DRA with Enhanced Isolation for LTE Applications

A new two element hybrid MIMO DRA is presented for LTE operation. The presented MIMO having two elements excited with CPW feeding. This is operating under hybrid TM mode. MIMO is intended on partial ground with thickness of 0.035 mm, substrate (FR-4) with dielectric constant (εr) of 4.6, thickness 1.6 mm and loss tangent 0.019. The DRA is placed on the two elements individually. The dimensions of the presented MIMO are 90 X 107.8 X 13 mm3. The antenna gives a multiband to covers 0.8 GHz, 1.5 GHz, and 1.7 GHz for |S11| ≤ -10 dB. The proposed MIMO can cover LTE Band 5 and Band 6 at 0.84 GHz with operating band width of 83.2 MHz (0.8106 – 0.8938 GHz), LTE Band 21 at 1.5 GHz with operating band width of 45.4 MHz (1.4825 – 1.5279 GHz) and LTE Band 9 at 1.7 GHz with operating band with is 72.6 MHz (1.7382 – 1.8108 GHz). The simulated isolation of -74.96 dB, -75.53 dB and -81.41 dB are obtained with respect to the mentioned frequencies, respectively. MIMO provides very good radiation efficiency >140 % at band-1, > 81% at band-2 and >82% at band-3. The proposed antenna is discovered to attain good isolation, better impedance matching, low Envelope Correlation Coefficient (ECC) and adequate gain. Hence, This MIMO suitable for LTE applications. The HFSS software is used for the simulation.