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Engineering, Technology & Applied Science Research Vol. 9, No. 3, 2019, 4200-4202 4200  
  

www.etasr.com Alsaif: Compact Hexagonal Monopole Antenna for Lower 5G Bands 

 

Compact Hexagonal Monopole Antenna for Lower 

5G Bands 
 

Haitham Alsaif 

Electrical Engineering Department, 

College of Engineering, University of Hail, 

Hail, Saudi Arabia 

hal-saif@hotmail.com, h.alsaif@uoh.edu.sa 
 

 

Abstract—This paper presents a compact planar antenna with 

extreme wide band. The antenna is designed to cover the entire 

lower 5th generation operating bands ranging from 2.32GHz to 

more than 12GHz. This band also covers the IEEE 802.11 

a/b/g/n/ac. The patch geometry has been simulated using an 

industrial standard simulation software called CST MWS. The 

monopole is miniaturized with a total size of 23x24x1.2mm
3
. The 

radiator and the ground plane are printed on a substrate of 

Rogers Duriod RT 5880 with relative permittivity of 2.2 and loss 

tangent of 0.00009. The simulated reflection coefficient and 

radiation pattern results are presented. S11 parameter for the 

designed antenna is less that -10dB over the operating band, with 

lowest value of -32.5dB at 2.85GHz. The radiation pattern is 

presented at the two orthogonal planes, elevation (E plane) and 

azimuth (H plane). Simulated results show that the antenna is 

appropriate of lower 5G bands application and several other 

wireless systems. 

Keywords-5G; ultra-wide band; planar antenna 

I. INTRODUCTION  

In the near future, the global mobile data traffic is expected 
to yearly increase by a rate of 160% [1]. This massive growth 
is mostly caused by the implementation of Internet of Things 
(IoT) and mobile video streaming. There will be about 18 
billion devices using the IoT out of a total of 29 billion devices 
[2]. Therefore, the next wireless generation networks will need 
to overcome enormous demands of wider bandwidth at high 
frequency bands. The crucial constraint to deploy 5G networks 
in two years from now is the availability of frequency 
spectrum. Both lower and higher frequency bands are required 
for that. For early implementation of 5G, lower bands are 
perfect because of their properties such as wave propagation 
and spectrum availability. The major frequency bands located 
between 2GHz and 6GHz are from 3.3GHz to 4.2GHz and 
from 4.4GHz to 4.990GHz. Those bands are currently being 
targeted for early trials of 5G systems in several countries. 
Table I demonstrations the country regions and the lower 5G 
bands [3]. 

To overcome such challenges and the in progress needs, an 
ultra-wide band (UWB) antenna has been designed. The 
monopole operates over a frequency band ranging from 
2.32GHz to more than 12GHz, which include all the frequency 

bands allocated for lower 5G systems. It is a model candidate 
for new generation devices such as tablets and mobile phones 
etc. Additionally, this band also fulfills the regulations of the 
UWB technology set by the Federal Communication 
Commission (FCC) [4]. Moreover, the designed patch covers 
several spectrum bands such as the IEEE 802.11 a/b/g/n/ac 
standards for Wi-Fi. Different new ultra-wideband antennas 
with various designs (rectangular, circular, Vivaldi, elliptical, 
etc.) have been designed [5-13]. The designs differ in terms of 
main parameters such as frequency bands, radiation, gain, and 
physical size. Some of these designs have shortages in their 
operating frequencies which do not include UWB set by FCC 
(3.1 to 10.6GHz). The suggested planar antenna in this paper is 
competitive with many of the previously published designs and 
has reduced size.  

TABLE I.  REGIONS WITH EXPECTED LOWER 5G SPECTRUM BANDS 

Region Frequency bands (GHz) 

Europe 3.4-3.8 

China 3.6, 4.4-4.5, 4.8-4.99 

Japan 3.6-4.2, 4.4-4.9 

Korea 3.4-3.7 

USA 3.1-3.55, 3.7-4.2 

 

II. ANTENNA DESIGN CONFIGURATION 

Figure 1 reveals the geometric shape labeled with 
parameters of the proposed monopole antenna and its 
parameters after optimization are shown in Table II. The patch 
has a miniaturized size with 25mm width and 23.5mm length 
and printed on a thick 1.2mm substrate of Rogers Duroid 
RT5880Lz that has relative permittivity εr=2.2 and loss tangent 
δ=0.0009. As shown in Figure 1, the patch is consisting of a 
main hexagonal shape radiator attached to thirteen smaller two 
sizes hexagonal radiators at the edges. The radiator is fed using 
coplanar waveguide (CPW) through a characteristic impedance 
of 50Ω. The microstrip line has 9.5mm length, 2.2mm width 
with 0.4mm as a separation gap from the ground plane at each 
side. The ground is containing two slots which improve the 
impedance matching. These slots are 5mm long and 0.5mm 
wide.  

Corresponding author: Haitham Alsaif 



Engineering, Technology & Applied Science Research Vol. 9, No. 3, 2019, 4200-4202 4201  
  

www.etasr.com Alsaif: Compact Hexagonal Monopole Antenna for Lower 5G Bands 

 

 

Fig. 1.  Design of monopole antenna configuration with labeled 
parameters  

TABLE II.  DESIGNED ANTENNA PARAMETERS AFTER 
OPTIMIZATION 

Variables L W H 

Dimensions (mm) 23.5 25 1.2 

Variables Wf Lf W1 

Dimensions (mm) 2.2 9.5 6 

Variables Wg Lg L1 

Dimensions (mm) 11 7 5 

 

  
Fig. 2.  The proposed antenna from simulation software CST Microwave 

studio 

III. RESULTS AND DISCUSSION 

The optimized reflection coefficient (S11) in dB as a 
function of frequency in GHz is plotted in Figure 3. It displays 
the extreme-wide bandwidth by which the design is 
characterized, from 2.32GHz until more than 12GHz which 
covers the whole FCC UWB set for such wireless applications 
as well as all for lower 5G bands in regions like Europe, China, 
Korea, Japan, and United States of America (Table I). The 
reflection coefficient or S11 has three resonant frequencies 
which are 2.82GHz, 6.1GHz, and 9.3GHz. As part of the 
parametric study for the proposed monopole antenna, several 
substrate materials have been tested and studied such as Rogers 

RT 5880 (εr=2.2), Rogers RT 5880Lz (εr=1.9), FR-4 (εr=4.3), 
and Polymide (εr=3.5). 

The tested materials are popular for such types of antenna 
designs. All reflection coefficients which represent the 
impedance matching for these materials are plotted in Figure 4. 
It can be observed that Rogers Duroid RT 5880, with 2.2 
relative permittivity provides the best impedance matching and 
covers wider operating frequency. In addition, its reflection 
coefficient is lower than the common -10dB standard along the 
entire bandwidth, from 3.1GHz to 10.6GHz. Figure 5 reveals 
the monopole power gain over the operating frequency in GHz 
versus the gain in dB. The design is characterized by high 
power gain that reaches more than 5dBi. Figure 6 demonstrates 
the normalized radiation pattern at the two main orthogonal 
planes in polar form at 2.82GHz, 6.1GHz, and 9.3 GHz. 
Generally, the radiation pattern has an omnidirectional shape 
with minor distortions at high frequencies due to the increase in 
power gain. Thus, the proposed antenna design can be placed 
in a wireless system at any position. 

 

 

Fig. 3.  Simulated reflection coefficient S11 vs operating frequency 

 

 
Fig. 4.  Reflection coeffecientS11 vs operating frequency for several 

substrate materials: Rogers RT 5880 (εr=2.2), Rogers RT 5880Lz (εr=1.9), 
FR-4 (εr=4.3), and Polymide (3.5) 

 

 

Fig. 5.  Simulated power gain of the proposed antenna 

3 4 5 6 7 8 9 10 11 12
0

1

2

3

4

5

6

Frequency (GHz)

P
o
w
e
r 
G
a
in
 (
d
B
)



Engineering, Technology & Applied Science Research Vol. 9, No. 3, 2019, 4200-4202 4202  
  

www.etasr.com Alsaif: Compact Hexagonal Monopole Antenna for Lower 5G Bands 

 

  

 
 

 
 

Fig. 6.  Normalized radiation pattern for E and H planes in polar form at 

the resonant frequencies 

IV. CONCLUSION 

A new compact extreme wide antenna has been presented 
in this paper. The patch has a very compact structure size, the 
overall volume is 23×24×1.2mm

3
 printed on a substrate of 

Rogers Duroid RT5880 with 2.2 relative permittivity and 
0.00009 loss tangent. The proposed monopole has the ability to 
operate over a bandwidth from 2.32GHz to more than 12GHz. 
The maximum obtained power gain is 5.89dB with an omni-
directional radiation pattern which is the optimum possible 
pattern for such antenna type. Thus, the design is appropriate 
for lower 5G wireless system applications at many countries. 
Also, the design is appropriate for ultra wide band wireless 
systems since the bandwidth covers the entire FCC band 
allocated for such systems. Design and simulation have been 
conducted using the industrial standard simulation software 
called CST Microwave studio. More miniaturizing strategies 
can be applied for further structure size reduction in the future. 
In addition, the design can be fabricated and experimentally 
measured. 

ACKNOWLEDGEMENT 

The author would like to express his thanks to the deanship 
of scientific research at University of Hail (UOH)l in Saudi 
Arabia for supporting this project (BA-1512). 

REFERENCES 

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[2] Ericsson Mobility Report. November 2016, Ericsson, 2016 

[3] GSMA, 5G Spectrum–Public Policy Position, GSMA, 2018 

[4] FCC, Third Memorandum Opinion and Order and Memorandum 
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2010 

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[10] O. M. H. Ahmed, A. R. Sebak, T. Denidni, “Compact UWB 
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[13] F. Zhu, S. Gao, A. T. Ho, C. H. See, R. A. Abd-Alhameed, J. Li, J. 
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