Design and Minimization of Mutual Coupling Steered Array Lens
Antenna for 5G Communication
ROOPASHREE D.1, SHRUTHI. K. N.1, R. BHAGYALAKSHMI1, CHAITHRA K. N.2
1Department of Electronics and Communication, Government Engineering College, Hassan, INDIA
2Department of Electronics and Communication, NITTE Institute of Technology, Bangalore
INDIA
Abstract: Examining and evaluating the improved microstrip patch antenna to enhance the performance by the
initial objectives are the main contribution of this paper. To achieve multiband operation, the patch's shape is first
adjusted later microstrip patch with the slot presented. With the help of the Ansoft HFSS antenna simulator,
functional analysis has been shown to examine the impact on antenna resonant frequency. A probe-driven
microstrip patch antenna imprinted on FR4 epoxy substrate with 1.6mm thickness and a dielectric constant of 4.4 is
developed in this work via the HFSS tool for wireless applications operating between 2 to 5GHz. To achieve
multiband operation, the structure of the patch is varied. The impacts on antenna resonant frequency are examined
through numerical simulations. The length, as well as the width of a traditional patch antenna, is initially computed,
and further, an appropriate patch dimension of 28.3mm x 36.9mm has been determined. For multiband operation
over the frequency ranging between 2 and 5GHz wireless applications, a probe-driven microstrip patch antenna
imprinted on FR4 epoxy substrate with 1.6mm thickness and a dielectric constant of 4.4 is built via the HFSS tool.
The proposed architecture of a traditional microstrip patch antenna is imprinted on an FR4 epoxy substrate with a
1.6mm thickness and a 4.4 dielectric constant. The proposed antenna design is illustrated for the 3D structure of the
Mutual Coupling Steered Array-Lens Antenna System (MPA) with an improved patch. To achieve multiband
operation, two slots are inserted on the edges of the patch, and both the slots are 2mm wide, as well as the depth of
the slots is modified to see how it corresponds to the resonant frequency. This work is mainly concentrated on (i)
Examining as well as evaluating the improved microstrip patch antenna to enhance its performance, (ii) Examining,
evaluating, as well as assessing the performance of an improved split ring resonator metamaterial, and (iii)
Exploring, analyzing, as well as evaluating the performance of dielectric lens base patch array antennas and (iv)
Developing as well as analyzing the transmission line phase shifter. The groundwork for developing this work is
being carried out, and a comparative study is made on (i) techniques for improving the antenna's performance
through the application of a modified patch antenna, a Modified split ring resonator, a Dielectric lens structure, and
Transmission line phase shifter.
Keywords: MPA, Line phase shifter, 5G, Modified patch Antenna, and Microstrip antenna.
Received: October 19, 2021. Revised: October 22, 2022. Accepted: November 24, 2022. Published: December 31, 2022.
1 Introduction
In superior execution airplanes, space apparatus,
satellites, rocket applications, portable radio, and
remote interchanges where size, weight, cost,
execution, simplicity of establishment, and
streamlined profile are limitations, low-profile
receiving wires might be required. To meet these
necessities, Microstrip receiving wires can be
utilized. Radiation execution can be improved by
using appropriate plan structures. The utilization of
high permittivity substrates can scale down
Microstrip receiving wire size. Thick substrates with
a lower scope of dielectric offer improved
proficiency and vast transmission capacity; however,
it requires a bigger component size. Microstrip radio
wire with a superconducting patch on a uniaxial
substrate gives high radiation productivity and gain
in millimeter frequencies. The width discontinuities
in a Microstrip fix lessen the length of reverberating
Microstrip receiving wire Permittivity, Metamaterial,
permeability, return loss, MPA, and Mutual coupling
steered array and radiation effectiveness also. The
appropriate impedance matching throughout the
corporate and series taking care of cluster design
gives high productivity Microstrip receiving wire.
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DOI: 10.37394/232017.2022.13.20
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An Antenna array cluster is a bunch of N spatially
isolated antenna wires utilized to coordinate
emanated power towards an ideal rakish area. When
an exhibit has been intended to concentrate on a
specific heading, it turns into a straightforward make-
a-difference to guide it toward another course by
changing the general periods of the cluster
components, which is known as directing or
checking. Close to focal points are fundamentally
used to collimate episode different energy to keep it
from spreading in undesired headings. By
appropriately molding the mathematical setup and
picking the suitable material for the focal points, they
can change different types of disparate energy into
plane waves. Exploratory approval of such focal
points and extensive finishes by involving horn
antenna wires or coaxial-to-waveguide changes as an
essential source to enlighten the focal point. Such
feed techniques cause an expansion in the profile of
the Luneburg focal point by the voluminous size of
the taking care design, making in-board
reconciliation of such gadgets extremely challenging.
Additionally, the round locus of central marks of
such focal points needs to be corrected for
beneficiary exhibits, which are, by and large planar.
Henceforth represent-day correspondence world
examination of the radiation example of the focal
points. They use a reasonable methodology and
describe the essential radiators that are substantial
anywhere in complex, challenging, and fundamental
angles. To avoid grating lobes, the gap between
elements in steering antennas should be within 0.6.
Because the atoms are closer and interact more
strongly in this circumstance, the mutual coupling
suffers. Many wireless antenna applications demand
antennas to have a compact form factor while still
having a high gain, substantially higher than an array
of the same size. Mutual coupling between antenna
array elements is crucial if the element spacing is
narrow. It must be quickly considered in the design
process, as it can result in substantial degradation in
an antenna's overall performance. Many strategies for
reducing mutual coupling, such as antenna arrays,
have been presented in the literature. To construct a
small beamforming lens-fed antenna array at 24
GHz, In [10], the authors proposed a two-layer
Rotman lens-fed Microstrip antenna array. In the era
of SiP, a multilayer implementation of the lens-fed
antenna array would be advantageous, as it is a
simple technique to create a beamforming module,
[11]. Low profile substrate integrated planar HMFE
lens antenna using metamaterial for wideband
operation was presented in [12]. For compactness,
the authors suggested in [4] combining a typical
conical horn antenna with a dielectric flat transmit-
array perforated lens.
The focal points give collimation and wide-end
guiding and go about as rough. Radom gives
successful insurance to the cluster, which is the most
appropriate to a sea climate with high directivity. The
collimation property of dielectric focal points over a
multi-band set of little-size fixed radio wires was
discussed. They have likewise planned a Microstrip
cluster radio wire with its printed feed network on a
solid substrate for the upgrade with a dielectric focal
point and acquired further increase, [13] which
means a compelling bigger radio wire. Actual
conservativeness could now be accomplished by
diminishing the number of components in
consonance with the collimation given by the focal
point, [8], [9]. From that point forward, Metamaterial
protection was utilized to alleviate the ascent in
standard coupling brought about by the decrease in
component distance. Metamaterials are originally
arranged composite materials with extraordinary
highlights not found in nature. They fostered a basic
methodology for diminishing standard coupling
between two MTM-roused electrically small
receiving wires that are firmly dispersed, [7] rely
upon self-scratch-off of the instigated shared ground,
are close to handling flows, and require no additional
development, [5]. For microwave and optical
applications, metamaterials are garnering increasing
study interest. Metamaterials are materials that can
display electromagnetic properties that are not
typically found in naturally existing materials, [1].
Split ring resonators (SSR) are one of many types
used in Metamaterial design because they have
negative permittivity and permeability around their
resonant frequencies. In [2], [3], [4], [5], [6], [7], [8]
a range of SRR structures – square, circular,
triangular, and elliptical – have been proposed and
researched, To produce multi-resonant behavior,
single, double, and triple-ring hexagonal and
circular-shaped SRRs are built and simulated using
MATLAB 2017 and HFSS simulators. Negative
permittivity and permeability bandwidths are
demonstrated using electromagnetic characteristics,
[10].
Based on a detailed literature survey on mutual
coupling steered array lenses for different
applications, it is concluded that there are many gaps
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DOI: 10.37394/232017.2022.13.20
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in the minimization of mutual coupling, mainly in 5G
communications, [17]. Mutual coupling plays a
significant role in current communication
technologies; therefore, this work is majorly
concentrated on the design of two rings hexagonal
split ring resonator, which is used to design the MPA
antenna. One of the ways to minimize mutual
coupling is by considering a linear phase shifter,
dielectric lens structure, and split ring resonator, [14],
[15].
This paper presents a brand-new compact, low-cost
patch array antenna with beam steering functionality
and mutual coupling reduction between the patches.
Beam steering and reduced mutual coupling are made
possible by adding a modified hexagonal split ring
resonator metamaterial structure in one of the 1 X 2
patch arrays. An antenna array can achieve a mutual
coupling reduction of about 4 dB at the operational
frequency with patches spaced 0.25 o apart. The left
and right produce a beam scanning of -200 to +200
changed patches, respectively. The simulation
findings utilizing experimental measurements are
used to validate the outcomes of the manufactured
prototype antenna. This proposed method for
constructing beam steering arrays also lessens the
mutual coupling impact between microstrip patch
array antennae. It is efficient to perform MPA by
altering one of the patches. By changing the left and
suitable patches in a 1x2 patch array-based antenna, a
+200 and -200 beam tilt can be obtained, with mutual
coupling reduced by about 4.5 dB. The proposed
antenna is made of inexpensive FR4 epoxy and is
suitable for 2.5GHz communication systems, [16].
2 Design of Proposed Two Rings
Hexagonal Split Ring Resonator
The main aim of this work is to analyze the
metamaterial structure and examine its electrical
characteristics. The first objective is to split ring
resonator metamaterial with a hexagonal shape,
discussed through simulation graphs via the HFSS
simulator to verify the electrical factors such as
permeability and permittivity. The objective of this
work is to design the following.
To design a metamaterial structure
computationally and examine its electrical
characteristics.
Examining the antenna system of the lens.
Determining the electrical characteristics like
permeability, refractive index, and permittivity
from a metamaterial framework.
Design of the lens antenna system.
Table 1. Optimized Results Parameters of two-
ring HSRR
With the help of simulation tools such as Ansoft
HFSS, a hexagonal split ring resonator comprising
two rings was developed with an operating frequency
of 2.6 GHz. Fig.1 represents the schematic geometry,
and the fabrication of two HSRR rings with six
segments, which are illustrated in Fig. 2. A metal
ring produced on a dielectric substrate (FR4) with 4.4
relative permittivity constitutes a structure.
Return Loss Analysis: To compute the HSRR return
loss value for two rings, a magnetic field is excited
perpendicular to the split ring, and an electric field is
closely parallel to the split ring architecture via two-
wave ports. A return loss value of -20.8829 dB is
obtained when it is done. To achieve an appropriate
Return Loss Value, a frequency ranging between 1
and 5 GHz and 401 frequency samples were chosen
over this frequency range. Fig.3 illustrates that at 2.6
GHz, a Return Loss of -20.8829 dB is accomplished.
The return loss is reduced at the central frequency.
Analysis of Negative permittivity and
permeability plot for Two Rings HSRR: Fig.4
illustrates the genuine parts, and Fig.5 illustrates the
imaginary parts of permittivity and permeability for a
two-ring HSRR. These exhibit a hexagonal-shaped
SRR, including a single ring with non-positive
absolute effective permittivity and permeability at a
frequency of 2.6 GHz. The permittivity and
permeability were determined to be -20.8829 and -
0.4911, respectively, at this resonant frequency,
indicating that the intended structure functions as a
left-hand metamaterial. Using the Ansoft HFSS
antenna simulator, an NZIM (near zero-index
Sl.
No.
Design parameters
Value
Range
1
Height of dielectric
substrate
1mm
2
The gap between split
rings
0.08mm
3
Width of the strip
0.866mm
4
The radius of the outer
polygon
4.75mm
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metamaterial) lens is developed and combined with a
standard patch antenna to maximize the gain of an
antenna following the first two objectives to analyze
as well as implement the lens antenna systems. The
broadside efficiency of a Microstrip Patch Antenna
for WLAN applications is increased in this work by
employing a superstrate structure that is made up of
an array of 7X7 metamaterial unit cells. A metal strip
is inserted into the typical mirrored S-like shape to
produce the suggested metamaterial unit cell. The
unit cell examination and parameter extraction via
periodic boundary constraints are employed to verify
the behavior of the near-zero index. It also
demonstrates the substantial decrease in the size of
individual cells. Simulation findings show that the
gain was increased by 1.56 dB over a typical patch
antenna when employing the NZIM (Near Zero Index
Metamaterial) lens. The broadside gain of the
Microstrip Patch Antenna is increased by utilizing
HFSS and a superstar. In the same way, the half-
power beam width is reduced by 200 in both E-plane
and the H-plane. The following sections examine as
well as analyze the results in detail.
Calculating for SRR in HFSS tool: The resonant
frequency of HSRR is approximated using a
statistical model. The framework also estimates how
the resonance frequency will vary as the angle of
rotation between the inner and outer polygons ranges.
It has been analytically verified that the resonance
frequency of 2.5GHz can be attained.
Empirical Formulae: With the help of the below
equation, the Resonant Frequency 󰇛) of the HSSRR
can be calculated

󰇛󰇛󰇜󰇜 … (1)
Here, the effective radius of HSSRR is represented
by and its expression is as follows:
 󰇥
󰇦
 .................... (2)
Here N=6, Equivalent inductance is represented by
 and its expression is represented as follows:
 󰇡
󰇢. (3)
Here, the strip width and perimeter are represented
by c and respectively, and the expression is
illustrated as indicated in the below equation.

………………………… (4)
The equivalent capacitance of the structure is
indicated by  and the expression is given as
follows:
 󰇡󰇥
󰇦󰇢󰇡
󰇢
󰇡󰇥
󰇦󰇢 …………… (5)
Where
 and  is the capacitance per unit
length of the hexagonal SRR

󰇛󰇜󰇥
󰇦󰇥
󰇦….
(6)
Now the upper half-ring (), as well as the lower
half-ring () capacitance, can be simply calculated
from as well as  as follows:
󰇣󰇥
󰇦󰇤………… (7)
And
 󰇣󰇥
󰇦󰇤…………….. (8)
the capacitance because of split gaps in the rings is
indicated by and can be approximated using the
equation 
Here the permittivity of free space 󰇡

󰇢 is indicated by  as well as the relative
permittivity is indicated by and is different for
different materials.
Calculating the resonant frequency of HSRR: The
necessary dimensions of HSSR can be acquired by
specifying the HSRR dimensions or an input
parameter employing a MATLAB code;
correspondingly, the mat lab code can also be used to
determine the HSRR for a specific operating
frequency. Initially, the SRR is designed as a single-
ring hexagonal-shaped SRR with various side
lengths. As illustrated in Fig.1, the side lengths
selected for the SRR-1 are 3mm, SRR-2 is 2mm, and
SRR-3 is 1mm. A metal ring produced on a dielectric
substrate RO4003 with 3.55 relative permittivity
constitutes the structure. 8mm x 8mm x 0.81mm is
the dimension of the substrate. The metal rings
possess a width (w) and gap width (w) of 0.33mm.
During SRR modeling, the return loss is considered
one of the most significant parameters. Fig. 2 shows
the amplitude in dB of the S21 factor for single-ring
unit cells such as SRR-1, SRR-2, and SRR-3. The
resonance frequency for SRR-1 is 5.1GHz with a
length of 1mm; for SRR-2, the resonance frequency
is 7.3 GHz with a 2mm length; and for SRR-3 with a
side length of 3mm, the resonance frequency was
found to be 12.3GHz which is illustrated in Fig.3.
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The resonant frequency switches from lower to a
higher frequency, i.e., 5Hz to 10GHz whenever the
capacitance is reduced. The side length decreases
from 3mm to 1mm. As a result, by varying the side
length of SRR, one can achieve the necessary shift in
frequency. Figure 3 depicts an essential building
component of the NZIM superstrate, the
metamaterial unit cell, used to enhance MPA gain.
These unit cells are printed on a single side of a
0.8mm thick FR4 substrate. Ax = Ay = 4.5 mm,
L1=4.2 mm, L2=1.725 mm, L3=1.2 mm, W1=4.3
mm, W2=3.5 mm, W=0.25 mm are the design
parameters of the NZIM unit cell with the best
possible values for near-zero refractive index
performance at 5GHz frequency band. By varying
the performance parameters of the NZIM unit cell,
the frequency band associated with a near-zero
refractive index can also be varied. The unit cell is
again simulated using ANSYS HFSS with PEC and
PMC boundary constraints. The scattering
parameters are used to determine the effective
medium properties, such as permittivity, refractive
index, and permeability, as illustrated in Fig.6, Fig.7,
Fig.8, and Fig.9, respectively. As shown in Figure 5,
applying the NZIM unit cell results in a substantial
decrease in the unit cell size. The overall antenna
system's efficiency has been examined. The gap
between the primary patch antenna and the lens has
been tuned to minimize the coupling between the
patch antenna and the lens. The lens structure is
positioned at h = 40 mm above the patch to achieve
this. This height is typically λo/2, wherein the MPA's
operating wavelength is represented by λo. The lens
width and length are set to match the patch's
broadside radiation for adequate coverage. Figure 6
shows the gain of a Microstrip patch antenna along
with an NZIM lens. 4.28 percent and 5.46 dB are the
impedance bandwidth and gain of a Microstrip patch
antenna that is achieved. The linear plot of the
radiation pattern in the E plane and the H plane
demonstrates the convergence of the radiated beam,
which is illustrated in Fig.10 and Fig.11. HPBW in
the H-plane (H) has been reduced from 720 to 510. In
contrast, HPBW in the E-plane (E) decreased from
900 to 580. As a result, the idea of gain enhancement
by beam convergence is proven.
This work provides a hexagonal-shaped Split Ring
Resonator built on Rogers' substrate. Various
magnetic resonances specified by different concentric
rings in the unit cell induce multi-resonant
phenomena in the microwave regime. To analyze and
plot the S-parameter of a hexagonal-shaped split ring
resonator over a frequency range, the ANSYS HFSS
tool is often employed. The required frequency can
be achieved by varying the side length of SRR,
which is demonstrated through simulation by
employing HFSS. The occurrence of non-positive
permeability bandwidths is verified using
electromagnetic characteristics. The developed
HSSRR is considered one of the promising platforms
for applying metamaterial in many parts of the
electromagnetic spectrum, particularly in device
miniaturization. Fig.12 and Fig.13 illustrate the
results obtained by integrating SRR-1 and SRR-2 in a
hexagonal-shaped SRR with two resonant
frequencies. Likewise, a three-ring hexagonal-shaped
SRR is built by combining SRR-1, SRR-2, and SRR-
3 to obtain a three-resonant frequency. Fig. 14
represents the magnitude spectra of the S21
parameter for two rings, and Fig. 15 illustrates the
magnitude spectra of the S21 parameter for three
rounds of HSSRR. SRR with two rings resonates at
5.1 GHz and 7.4 GHz frequencies. However, SRR
with three rings resonates at 5.1 GHz, 7.5 GHz, and
12.3 GHz frequencies. As a result, multi-band
operation is possible. Table 1 depicts the
resonance frequencies of all hexagonal-shaped
structures.
3 Results and Discussions
The dip in Fig. 2 is achieved at 2.4GHz and
corresponds to the resonant frequency of the
traditional patch antenna. At this frequency, the
return loss is -19dB. The antenna absorbs the
maximum input energy whenever the return loss is
minimal, i.e., minimum reflection. The gain for
MPA, simulated via HFSS, is found to be 3.0dB and
is illustrated in Fig. 3. This complies with the
Microstrip Patch antenna industry benchmark. Two
bands of resonant frequencies are produced at
2.45GHz with -15dB return loss, as well as another
frequency band at 4.6GHz with -18dB return loss,
which is illustrated in Fig. 5. A resonant band is
defined as a frequency band possessing a return loss
of less than -10dB. The optimized MPA has a gain of
4.6dB, shown in Fig. 6, and when compared to a
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traditional patch antenna, the growth is improved by
1 dB.
Furthermore, the slot's length immediately prior to
the patch was modified to see how it varies with
frequency. Table 1 shows the results, whereas Fig. 7
shows the graph that corresponds to them. The
resonant frequency at 4GHz advances towards 5GHz
as the length Lx1 is increased from 1mm to 6mm, as
shown in Fig. 4. Antenna developers employ this
technology to design antennas varying between 2 to
5GHz applications. Furthermore, a slotted single
probe feed microstrip patch antenna is presented. The
patch consists of a rectangular slot that enables dual-
band operation. At a frequency of 2.4 GHz, the
primary antenna is being devised with a Wi-Fi
system. The antenna developed using HFSS software
exhibits excellent characteristics for applications
such as wireless communication and S-band ranging
from 2 to 5GHz.
Design of a Typical Microstrip Patch Antenna:
The traditional patch antenna's length, as well as
width, can be estimated. Fig.1 illustrates the
configuration of a conventional microstrip patch
antenna imprinted on FR4 epoxy substrate with
1.6mm thickness and 4.4. dielectric constant. The
dimensions of a patch and substrate are 28.3mm x
36.9mm and 86mm x 96mm, respectively.
Suggested Microstrip Patch Antenna with Slot:
Fig.2 illustrates a 3-dimensional structure of the
suggested MPA that includes a slot. A rectangular
space is inserted into the patch to achieve the
optimum dual-band operation. The antenna's length
and width have been reduced to 4mm x 15mm. The
resonant frequency of the typical patch antenna is
2.4GHz, achieved by dip, and is depicted in Fig. 1.
At this 2.4GHz frequency, the return loss obtained is
-19dB. The antenna receives the maximum input
energy whenever the return loss is minimal, i.e.,
minimum reflection. By employing HFSS, the gain
for MPA simulated was found to be 3.0dB, shown in
Fig.1. This complies with the Microstrip Patch
antenna industry norm. Dual-band operation is
described in Fig. 3. The 2.2 GHz is the initial
frequency similar to the standard MPA, and 4.55
GHz is the subsequent frequency. The return loss
observed in these two bands is much lower than the
required, i.e., not more than -10dB. Figure 4 shows
that the gain attained for the 2.4 GHz band is 3.1dB,
which can be acceptable, and a 0.1dB increase in
revenue exists.
Parametric Analysis of Microstrip Patch
Antenna with Slot: After that, to examine the
impact on the resonant frequency, the slot length
was varied with the specified 2mm slot width.
Table 1 illustrates the outcome, whereas Fig. 5
shows the graph that corresponds to that result.
Fig.5 demonstrates that whenever the rectangular
slot length is modified, there is no variation in
the first, i.e., 2.4GHz band, while the resonant
frequency surpasses 5GHz in the subsequent
band. This information helps antenna engineers
identify the suitable frequency band for their
applications.
Initially, we demonstrate the application of a
modified split ring resonator metamaterial structure
to minimize mutual coupling in a Microstrip patch
antenna array. The suggested MSRR unit cell
comprises two nested rings with two symmetrical
splits. At a frequency of 2.4 GHz, the primary
microstrip patch antenna is operated, and the distance
between the edges of the primary antenna element is
31.5mm and approximately 0.25 λ0. The antenna
array isolation is considerably improved by
introducing the MSRR Metamaterial structure on the
radiating patch of the antenna array placed on the
right side. The results obtained from the simulation
illustrate that the isolation is minimized by not less
than 12 dB and by not affecting the frequency of
operation or radiation patterns. Fig.15 outlines the
conceptual Microstrip antenna array with MSRR
metamaterial structures. The variety of an antenna is
constructed on an FR4 with εr 4.4, δ=0.02, h = 1.57
mm relative permittivity, loss tangent, and thickness,
respectively. Two similar rectangle patch antennas
featuring coaxial feeding constitute an antenna array.
The antenna array possesses a ground plane at the
end. The arrays of antennas are designed to operate at
2.4 GHz and keep 31.5 mm edge-to-edge spacing. As
seen in Fig. 15, the MSRR unit cell is made up of
two nested rings, and each of these rings consists of
two symmetrical splits. The unit cells of MSRR are
inserted between the two antennas on the left side
with 1 mm spacing between them. Lgnd = 70 mm, L =
28.3 mm, Wgnd = 130 mm, W = 36.5 mm, r1 = 2.5
mm, r2 = 2 mm, d = 31.5 mm, d1 = 0.25 mm, d2 =
0.25 mm, k = 0.08 mm are the best possible antenna
array dimensions to obtain maximum isolation. A
simulation model in ANSYS HFSS was used to
analyze the efficiency of the suggested MSRR-
loaded antenna array.
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Ansoft LLC
Return Loss Plot
HFSSDesign1 ANSOFT
0.00 Curve Info
dB(S(1,1))
Setup1 : Patch1
-2.50
-5.00 Name X Y
m1 5.0950 -10.0070
m2 5.2075 -17.2390
-7.50
m3 5.3000 -10.6052
-10.00 m1 m3
-12.50
-15.00
m2
-17.50 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00
9.00
10.00
Freq [GHz]
Fig. 1: 3D Model of Single rectangular
Microstrip patch Antenna
Fig. 2: The plot of the Return loss of Basic
patch antenna without NZIM lens
Fig.3: The schematic diagram of the NZIM unit
cell
Fig. 4: The schematic diagram of the proposed
antenna with NZIM lens: (a) Top view (b) Side
view
Fig. 5: 3D polar plot of gain of Basic
patch antenna without NZIM lens
Fig. 6: 3D polar plot of gain of Basic patch
antenna with NZIM lens
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Fig. 7: Extracted Real and Imaginary Part of
Refractive Index for the Proposed
NZIM Unit Cell
Fig. 8: Extracted Real and Imaginary Part of
Permittivity for the Proposed NZIM Unit Cell
Fig. 9: Extracted Real and Imaginary Part of
Permeability for the Proposed Nzim
Unit Cell
Fig. 10: Simulated Radiation Pattern of Basic
Patch Antenna Loaded with Single
Layer- E-Plane
Fig. 11: Simulated Radiation Pattern of Basic Patch Antenna Loaded with Single Layer- H-Plane
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To assess the effectiveness of the planned patch-
modified antenna array using an MPA structure slot,
numerical simulation in ANSYS HFSS is employed.
Agilent Technologies' PNA Network Analyzer is
used to measure the antennas (E8363C, 10MHz-
40GHz). Fig. 3 depicts the experimental
configuration for measuring operating frequency. In
Fig. 3, the isolation S12 and return loss S11 plots of a
patch array antenna without patch modification are
shown in simulation and measurement. Similarly,
Fig.3 shows the simulated and measured isolation
S12 and return loss S11 plot of a left patch adjusted.
Once the MSRR structure is positioned on the left
side of an antenna array, the current present on the
right antenna element is low. A large amount of
current is associated with the MSRR Metamaterial
structure, which further allows for minimizing the
mutual coupling of the antenna array by using the
suggested MSRR structure, as shown in Fig.14. The
radiation patterns of the suggested antenna array with
MSRR Metamaterial structures and without MSRR
Metamaterial structures at the operating frequency is
illustrated in Fig.15. At the resonance frequency, a
small variation in the radiation patterns of antenna
arrays can be observed with MSRR Metamaterial
structures or without MSRR Metamaterial structures
and thereby indicating the suggested MSRR
Metamaterial structure to minimize mutual coupling
without impacting the properties of radiation.
Furthermore, a 1X2 Microstrip patch antenna array
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Fig. 12 Hexagonal SRR with two concentric rings simulated using
HFSS
Fig.13 Hexagonal SRR with three concentric rings simulated
using HFSS
Fig.13 Hexagonal SRR with three concentric rings simulated using
HFSS
Fig.14 The magnitude of S21 for SRR with two rings
Table 2. Summary of Simulation Results
with a 2.4 GHz resonant frequency has been
developed and used for the ISM band. Secondly, by
employing a modified split ring resonator
metamaterial structure as a unit cell, a metamaterial
lens is being developed and deployed on the top of
the Microstrip patch antenna array. All underlying
performance measures are measured without
Metamaterial and with Metamaterial during the
design optimization process. Polar plots, 3D radiation
plots, and S-parameter plots are used to describe the
simulation outputs. To increase performance and
minimize coupling effects, the metamaterial lens
increases, and its antenna gain has increased from 3
to 6.0. At 2.4GHz, a Microstrip Rectangular Patch
Antenna, including coaxial feeding, is constructed
with the help of FR4 dielectric material with 1.57
mm thickness and with 4.4 dielectric constants. The
best possible width, as well as the length of the patch,
were found to be 38mm as well as 28mm,
respectively. As illustrated in Fig.10, revised
metamaterial split ring resonators are positioned 10
mm above a 1 X 2 Microstrip patch antenna array
with a spacing of 32 mm between them with 1 mm
thickness FR4 dielectric material with 4.4 as the
dielectric constant. The MSRR unit cell is made up
of two nested rings, and each of these rings consists
of two symmetrical splits. The unit cells of MSRR
are inserted between the two antennas on the left side
with 1 mm spacing between them. Lgnd = 70 mm, L
= 28.3 mm, Wgnd = 130 mm, W = 36.5 mm, r1 = 2.5
mm, r2 = 2 mm, d = 31.5 mm, d1 = 0.25 mm, d2 =
0.25 mm, k = 0.08 mm are the best possible antenna
array dimensions to obtain maximum isolation and is
illustrated in Fig.13. A simulation model in ANSYS
HFSS was used to analyze the efficiency of the
suggested MSRR loaded antenna array. Fig. 14
illustrates the antenna array return loss with MSRR
Metamaterial structures. The antenna array radiation
pattern with MSRR Metamaterial structures and the
antenna array radiation pattern without MSRR
Metamaterial structures. The gain of the suggested
antenna array was approximately 6.4 dB, while the
gain of a patch array without Metamaterial was 3.7
dB. Compared to a patch array without Metamaterial,
the antenna array gain with Metamaterial was nearly
doubled. A probe-driven microstrip patch antenna
imprinted on an FR4 epoxy substrate with 1.6mm
thickness and a dielectric constant of 4.4 is developed
in this work via the HFSS tool for wireless
applications operating at 2.4GHz. Two hemispherical
Teflon lenses with 2.1 as the dielectric constant are
inserted just above patches to improve the gain. A
mathematical study of spacing between the patches
and their placement height is demonstrated. The
traditional patch antenna's length, and width, can be
estimated. A traditional microstrip patch antenna
configuration is imprinted on an FR4 epoxy substrate
with 1.6mm thickness and a dielectric constant of
4.4. The dimensions of the patch are 28.3mm x
36.9mm. Coaxial feeding is used to drive the
antennas. The spacing between the antennas must be
tuned to 62mm to ensure low mutual coupling and
optimum gain. Fig.14 shows a 3D representation of
the suggested MPA array with the hemispherical
lens. Two hemispherical Teflon lenses with 2.1 as the
dielectric constant are inserted just above patches to
improve the gain. To achieve high gain, the
hemispherical lens' height, as well as the radius, must
be optimized. The dip is achieved at 2.4GHz and
corresponds to the resonant frequency of the
traditional patch antenna. At this frequency, the
return loss is -19dB and -23.6 dB for the first and
second antennae, respectively. The antenna absorbs
the maximum input energy whenever the return loss
is minimal, i.e., minimum reflection. The gain for
MPA, which is simulated via HFSS, is found to be
5.0 dB. This complies with the Microstrip Patch
antenna industry benchmark. The initial antenna's
resonance frequency is 2.4GHz, and the return loss is
-15dB. No resonant frequency modification exists,
even though 9dB reduces the return loss. The MPA
gain with a hemispherical lens is found to be 11dB.
Compared to a traditional patch antenna array, the
gain is increased by 7dB. The height at which the
hemispherical lens is set is then considered for
computational analysis to see how it affects the
antenna array's gain. The obtained outcomes are
mentioned in Table 2. It is seen that whenever
the antennas are placed nearer that point, the
antenna array gain reduces. This reduction is
caused because of the mutual coupling among the
array of antennas. Table 1 shows that the gain
reduces as the lens position height increases. This is
because the lens absorbs fewer electromagnetic
waves released by the patches.
4 Conclusion
A simple as well as cost-efficient transmission line
phase shifter is presented. A 1 X 2 microstrip patch
array antenna operating at 2.6 GHz is built using
transmission line feeding. Similarly, an FR4
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dielectric substrate with a dielectric constant of 4.4 is
employed with a 1.6 mm thickness. By the standard
route array antenna, variations in the transmission
line feeding approach are measured to produce
various phase shift values. Multiple lengths of
transmission line feeding are used for the phase
shifter. To obtain varied phase shift values, the HFSS
simulator tool is employed to develop various sizes
of transmission lines. FR4 dielectric substrate with
dielectric constant of 4.4 and 1.6 mm thickness is
used to create an array of 1 X 2 rectangular
microstrip patch antennas operating at a frequency of
2.5 GHz. 36.5 mm, as well as 27.5 mm, are the best
possible patch length as well as widths. 193 mm, as
well as 73.6 mm, are the length and width of the
substrate. We obtained various phase shift values by
using a relatively small delay line for the size of the
transmission line fed to a 1 X 2 microstrip antenna.
Fig. 3 shows how to obtain a +200-phase shift using a
50.4mm delay line on the right side.
Correspondingly, as illustrated in Fig. 1, a -+200
phase shift can be obtained by increasing the length
of the delay line by 46.4 mm on the left side. The
Return loss graph for an antenna array with a +200
phase shifter design operating at 2.6 GHz is shown in
Fig. 2. The red line in Fig. 3 represents a +200-phase
shift value when contrasted to the blue line, which
means a standard antenna array. It also shows that the
gain for the suggested antenna is roughly 4.8297dB
and is depicted in Fig. 4. Return loss graph for an
antenna array with a -200 phase shifter design
operating at 2.6 GHz is shown in Fig. 5. The red line
in Fig. 3, represents a -200-phase shift value when
contrasted to that of the blue line which means a
standard antenna array. Fig. 6 shows that the
suggested antenna exhibits a gain of approximately
5.0095 dB. In future work, Machine learning and AI-
based MPA antenna can be designed to optimize
further in terms of mutual coupling effects.
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research, at all stages from the formulation
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