A Compact Broadband Circularly Polarized Wide-Slot Antenna With Axial Ratio Bandwidth Encompassing LTE 42 and LTE 43 Standards of 5G Mid-Band

Abstract

This study presents a compact broadband wide-slot antenna with broadband left-hand circular polarization compatible with both LTE 42 and LTE 43 standards of 5G mid-band applications. The proposed antenna is fabricated on an FR4 dielectric substrate with overall dimensions of 0.41𝜆 𝑜 × 0.36𝜆 𝑜 × 0.02𝜆 𝑜 , where 𝜆 𝑜 is the free space wavelength at the resonant frequency of the antenna. The antenna ground plane is etched to form a square radiating slot with a pair of rectangular ground stubs that are diagonally placed inside the slot. On the other side of the antenna, the feed line is loaded by horizontal and vertical stubs to improve the coupling between the feed line and the square slot. To generate a circular polarization, the feeding stubs cooperate with the pair of rectangular ground stubs to excite the radiating slot of the antenna at two different feeding points whose currents have approximately equal amplitude and 90 o phase shift. The measured impedance bandwidth (BW) of the proposed wide-slot antenna is 16.2% (580 MHz along the band 3.3-3.88 GHz), while the observed axial ratio bandwidth (ARBW) is 12.2% (440 MHz in the 3.4-3.84 GHz band). The measured gain values are found to be larger than 2.5 dB along both standards of the 5G mid-band applications.INDEX TERMS Axial Ratio, circular polarization, wide-slot antenna, reflection coefficient, broadband.

Improved Bandwidth of Microstrip Wide-Slot Antenna Using Gielis Curves

“…For instant, the antenna proposed in [16] has wide impedance bandwidth of 148.6% and an acceptable gain of 4.7 dBi, its size is large. To remove this 2 challenge, wide-slot antennas with irregular shapes and parasitic elements are merged together [17][18][19][20][21][22][23][24]. For instance, an irregular polygonal shaped wide-slot has been proposed in [17] with reduced size and an impedance bandwidth of 127.5%.…”

“…Recently, a microstrip wideslot antenna based on a self-shape blending algorithm has been designed in [22] for working from 2.07 GHz to 5.94 GHz to cover WLAN and WiMAX bands. More recently, a compact circularly polarized wide-slot antenna with 16.2% bandwidth and gain larger than 2.5 dBi has been proposed in [23]. Considering the extent and variety of the researches done in increasing the wide-slot antennas bandwidth by changing the shape of the wide-slot, it is required to provide a general method for the investigation of the effect of the wide-slot with an arbitrary shape in the performance of this type of antenna.…”

Generalized Concept and MATLAB Code for Modeling and Analyzing Wideband 90° Stub-Loaded Phase Shifters with Simulation and Experimental Verifications

“…These phase shifters are commonly used in 5G and 6G beamforming systems [ 1 , 2 , 3 , 4 ]. The 90° phase shifters are also indispensable in exciting narrowband circularly polarized antennas [ 5 ] and broadband circularly polarized antennas [ 6 , 7 ]. In addition to these well-known applications, the utilization of the 90° microwave phase shifter extends to the design of balanced mixers, modulators, beam scanning, and so on.…”