Design and analysis of a Dual band Monopole Antenna for ... · each other loaded with a partial ground plane. ... band monopole antenna using defected ground structure ... inverted-L

International Journal of Applied Engineering Research ISSN 0973-4562 Volume 13, Number 16 (2018) pp. 12570-12581

© Research India Publications. http://www.ripublication.com

12570

Design and analysis of a Dual band Monopole Antenna for resonating

between Wi-Fi & Wi-Max Applications

1Mr. Prasanna Paga,2Dr. H.C.Nagaraj,3Dr.T.S.Rukmini

1Research Scholar, 2Professor & Principal, 3Professor, 1,2,3Department of Electronics and Communication Engineering, NREA,

Nitte Meenakshi Institute of Technology, Yelahanka, Bangalore, Karnataka, India.

Abstract

In the proposed work, a dual band antenna has been designed,

simulated and fabricated on a Rogers (RT/Duroid 5880tm)

substrate of permittivity 2.2 and thickness 1.6mm for resonating

between Wi-Fi and Wi-Max. The novely of the work lies in

using two conducting strips that are mutually perpendicular to

each other loaded with a partial ground plane. The proposed

structure resulted in a peak Gain of 7.62dB and 5.75dB for the

lower and the upper frequency bands respectively.

Keywords: Wi-Fi, Wi-Max, Monopole

INTRODUCTION

In recent years there has been a tremendous development in

the field of wireless communications. With the explosive

growth of different wireless standards supporting different

frequencies, the Antennas used in these devices need to

support a large number of wireless standards such as GSM,

Wi-Fi, Wi-Max, UMTS to increase the data rate and improve

the channel capacity along with reduction in antenna size.

The current Antennas need to be replaced with reconfigurable

Antennas that can dynamically change the radiation

characteristics of the Antenna in real time such as operating

frequency, polarization or radiation pattern In [1], the

authors had designed a Monopole Antenna on a FR4 substrate

for Wi-Fi and WLAN Applications. The peak Gain remained

at 2.04 dBi and 2.83dBi for Wi-Fi and WLAN Frequency

Bands respectively. In [2], the authors designed a dual band

Frequency reconfigurable Planar Dipole Antenna loaded with

a Dual-Band Artificial Ground plane The proposed Antenna

gave a Bandwidth of 12.5% and 6.7% at 2.4GHz and 5.2 GHz

respectively. In [3], a dual band parabolic slotted Ground

plane for Wi-Fi and WLAN Applications. The proposed

Antenna resulted in a Gain of 1.68dBi and 2.33 dBi for Wi-Fi

and WLAN bands respectively. In [4], a novel compact dual-

band monopole antenna using defected ground structure

(DGS) is presented. DGS is used in this antenna which has a

rectangular patch with dual J-shaped strips. It helps in

achieving a good resonant mode and good impedance

matching. The antenna gives a bandwidth of 400MHz and

530MHz for 2.5GHz and 3.5GHz respectively. It also gives

omnidirectional pattern and constant gain for both the

frequency bands. In [5], dual band David fractal Microstrip

patch antenna for GSM and WiMAX applications has been

proposed. The antenna resonates at 1.8GHz and 3.4GHz and

gives good radiation pattern and moderate gains of 6.93dBi

and 5.3dBi for 1.8GHz and 3.4GHz respectively. The antenna

gives a return loss of -18.7dB, -14.3dB for 1.8GHz and

3.4GHz respectively. The radiating structure resulted in a -

10dB impedance bandwidth of 55MHz and 31MHz, Gain of

6.93dBi and 5.3dBi for the lower and upper bands

respectively. The radiation pattern reported were

hemispherical for 1.8GHz and horizontal figure of 8 for

3.5GHz respectively. In [6], a novel triple-band microstrip-fed

planar monopole antenna with defected ground structure

(DGS) is proposed for WLAN and WiMAX applications. The

proposed microstrip-fed antenna consists of a rectangular

patch, dual inverted L-shaped strips and a defected ground.

The designed antenna can generate three separate resonances

to cover both the 2.4/5.2GHz WLAN bands and the 3.5GHz

WiMAX bands while maintaining a small overall size of

20mm × 27mm. A prototype is experimentally tested, and

experimental results show that the antenna gives good

radiation patterns and enough antenna gains over the

operating bands. In [7], a novel design of a pentagonal-shaped

planar dual-band monopole antenna has been presented. The

validated antenna is compact with a size of 57x50x1,6 mm3.

It is printed on an FR-4 substrate and fed by a 50 Ohm

microstrip line. The final circuit operates in the DCS

frequency band at 1.8 GHz and the WiMAX at 3.5 GHz. To

achieve such antenna, we have used different optimization

methods integrated in CST Microwave Studio. The obtained

results are compared with another electromagnetic solver

Ansoft’s HFSS. After the realization, we have tested and

validated this antenna. The measurement results present an

agreement with the numerical results. The Gain reported were

0.6dB and 3.56dB for lower and upper frequency bands

respectively. In [8], a planar dual-band monopole antenna is

presented for Global System for Mobile Communications

(GSM) band applications, which also have the potential to be

used for energy harvesting system. The proposed antenna

comprises of a ground plane at the back of the FR4 substrate

and three microstrip lines which are physically connected with

each other at the top surface of the substrate. The monopole

antenna achieves good return loss at resonance frequencies of

915 MHz and 1800 MHz with a bandwidth value of 124.2

MHz and 196.9 MHz respectively. The antenna gains of 1.97

dB and 3.05 dB are achieved at resonance frequencies of 900

MHz and 1800 MHz. Experimental results show good

agreement with simulated performance. The output from the

receiving antenna is also observed in order to analyze the

relationship of the power level and the distance between

transmitting and receiving antenna. This study is an early

investigation in designing the RF energy harvesting system to

mailto:[email protected]

mailto:principal@nmit.



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support green technology and sustain able development

particularly for Wireless Sensor Network (WSN)

applications.In [9], a compact triple-band monopole antenna

with two different slots for WLAN and WiMAX applications

is proposed and experimentally studied. The proposed antenna

with a size of 30mm × 25mm × 1mm is excited by a 50Ω

Microstrip feed line. The designed antenna obtains three

frequency bands through loading an inverted E-shaped slot

and an inverted C-shaped slot which incise the surface current

and change the path of the current on the rectangle patch. The

obtained results show that the designed antenna has

impedance bandwidths of 2.4GHz, 5.8GHz for WLAN and

3.5GHz for WiMAX. The return loss, radiation patterns and

peak antenna gains are presented using computer simulations

and measurements. In [10], a simple multiband metamaterial-

loaded monopole antenna suitable for wireless local area

network (WLAN) and Worldwide Interoperability for

Microwave Access (WiMAX) applications is proposed in this

letter. The rectangle monopole of the proposed antenna is

originally designed to resonate at around 5.2 GHz. When the

inverted-L slot is etched, the antenna produces a second

resonance at around 4.1 GHz. Then, with the addition of the

metamaterial reactive loading, the resonant frequency of the

antenna will be shifted down, and a third resonance covering

the 2.4-GHz band occurs. Consequently, the antenna can

cover the 2.4/5.2/5.8-GHz WLAN and 2.5/3.5/5.5-GHz

WiMAX bands with a very compact size of only mm.

Monopole-like radiation patterns and acceptable gains and

efficiencies have been obtained. Details of the antenna design

as well as the experimental results are presented and

discussed.

.

ANTENNA DESIGN

(a) (b)

Figure 1(a) Snapshot of the simulated Antenna (top view).

(b) Ground plane view

(a) (b)

Figure 2(a) Top view of the Fabricated prototype of antenna.

(b) Ground plane view of the antenna

METHODOLOGY

In the proposed work, a dual band Antenna has been designed,

simulated and Fabricated on a Roger’s(RT/Duroid) substrate

of permittivity 2.2 and thickness 1.6mm to tune between Wi-

Fi (2.4GHz) and Wi-Max 3.5GHz Frequency band. The

Length of the longer monopole section (L1) was selected to

tune to 2.4GHz frequency band of interest while the length of

the shorter monopole section(L2) have been selected to tune

to Wi-Max band. The length and width of the substrate have

been kept equal to 50mm × 25mm.the length and width of the

ground plane have been kept equal to 20mm× 12mm to give a

monopole like characteristic feature.

DESIGN EQUATIONS

𝐋𝟏 = 𝐋𝟐.𝟒𝐆𝐇𝐳 =𝛌𝐠

𝟒

(1)

Where L1=Length of the Main Monopole resonating at

2.4GHz.

𝜆𝑔=Guide wavelength.

𝜆𝑔 =𝜆0

√𝜀𝑟𝑒𝑓𝑓

(2)

Where 𝜀𝑟𝑒𝑓𝑓= Effective electrical permittivity of the dielectric

substrate.

𝜆0=Free space wavelength corresponding to frequency of

operation.

𝜀𝑟𝑒𝑓𝑓 = [(𝜀𝑟 + 1

2) + (

𝜀𝑟 − 1

2) (1 +

12ℎ

𝑊)

−1 2

]

(3)

Where.

εr = relative permittivity of the di-electric substrate.

W= Monopole Antenna width =3mm

h= substrate thickness=1.6mm



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Z=60

√𝜀𝑟𝑒𝑓𝑓𝑙𝑛 [

8ℎ

𝑊+

𝑊

4ℎ] (4)

Where Z=50 Ohms (port Impedance),

h = substrate thickness

W=Width of the Monopole.

L2=L 3.5GHz =𝜆𝑔

4 (5)

𝜀𝑟𝑒𝑓𝑓= Effective electrical

permittivity of the di-electric

substrate

Lw =6h+W (6)

Where Ls=Substrate Length

Ws=Substrate Width.

SIMULATIONS & MEASURED RESULTS

Figure 3. Simulated return loss plot of the monopole antenna resonating at 2.4GHz and 3.5GHz on Rogers(RT/Duroid) substrate

of permittivity 2.2.The corresponding return loss values are: -35.27dB and -25.985dB at 2.4 and 3.5GHz respectively.

Figure 4. Measured return loss plot of the monopole antenna resonating at 1.9GHz and 3.66GHz clearly showing a value of -

15.69dB and -13.94dB respectively as indicated by markers 1 and 3 on Rogers(RT/Duroid) substrate of permittivity 2.2.

1.00 1.50 2.00 2.50 3.00 3.50 4.00Freq [GHz]

-37.50

-25.00

-12.50

0.00

dB

(S

(1

,1))

HFSSDesign1return loss

m1

m2

Curve Info

dB(S(1,1))Setup1 : Sw eep

Name Freq X Y

m1 2.3636 2.3636 -35.2790

m2 3.5152 3.5152 -25.9852



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Figure 5. Simulated bandwidth of the monopole antenna resonating at 2.4GHz on Rogers(RT/Duroid) substrate of permittivity

2.2.The simulated values of the bandwidth reported is 0.4416GHz at 2.4GHz with -10dB impedance bandwidth extending

between 2.172GHz to 2.614GHz.

Figure 6. Simulated bandwidth of the antenna resonating at 3.5GHz on Rogers (RT/Duroid5880tm) substrate of permittivity

2.2.The -10dB impedance bandwidth extending between 3.299GHz to 3.856GHz giving a total bandwidth of 0.557GHz.



12574

Figure 7. Measured bandwidth of the Antenna resonating at 1.96GHz on Rogers (RT/Duroid5880tm) of Substrate permittivity

2.2.From the plot, it is clear that the value of the Bandwidth obtained is 0.672GHz with a -10dB impedance bandwidth extending

between 1.7 GHz to 2.37GHz respectively as indicated by markers 2 and 3.

Figure 8. Measured bandwidth of the Antenna resonating at 3.6GHz on Rogers (RT/Duroid5880tm) Substrate of permittivity

2.2.From the plot, it is clear that the value of the Bandwidth obtained is 1.25GHz with a -10dB impedance bandwidth extending

between 3.584 GHz to 4.835GHz respectively as indicated by markers 2 and 3.



12575

Figure 9. Simulated vswr plot of the antenna resonating at 2.4 GHz and 3.5GHz on Rogers (RT/Duroid5880tm) substrate of

permittivity 2.2.indicating a value of 1 and 1.12 at 2.4GHz and 3.5GHz frequency bands respectively.

Figure 10. Measured VSWR plot of the Antenna resonating at 1.96 GHz and 3.66GHz indicating a value of 1.48 and 1.52

respectively for the lower and the upper band respectively as indicated by markers 1 and 3 on Rogers(RT/Duroid) substrate of

permittivity 2.2.

1.00 1.50 2.00 2.50 3.00 3.50 4.00Freq [GHz]

0.00

50.00

100.00

150.00

200.00

225.00V

SW

R(1

)

HFSSDesign1VSWR

m1 m2

Curve Info

VSWR(1)Setup1 : Sw eep

Name Freq X Y

m1 2.4000 2.4000 1.0892

m2 3.5000 3.5000 1.1210



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Figure 11. Simulated radiation pattern of the Monopole Antenna on Rogers(RT/Duroid 5880tm)substrate of permittivity 2.2

indicating a peak boresight gain of 7.49dB under H plane at 2.4GHz as shown by marker m1.The radial axis represents the Gain(

in dB) while the angular axis represents the scan angle(in degrees)


indicating a peak boresight gain of 7.49dB under E plane at 2.4GHz as shown by marker m1.The radial axis represents the

Gain(dB) while the angular axis represents the scan angle(in degrees)

-36.50

-33.00

-29.50

-26.00

-22.50

-19.00

-15.50

-12.00

-8.50

-5.00

-1.50

2.00

90

60

30

0

-30

-60

-90

-120

-150

-180

150

120

HFSSDesign1h-plane 2.4Ghzm1

Curve Info

dB(GainTotal)Setup1 : LastAdaptiveFreq='2.4GHz' Phi='0deg'

Name Ang Mag

m1 0.0000 7.4946

-33.00

-26.00

-19.00

-12.00

-5.00

2.00

90

60

30

0

-30

-60

-90

-120

-150

-180

150

120

HFSSDesign1e-plane 2.4Ghz

m1

Curve Info


Name Ang Mag

m1 0.0000 7.4946



12577

Figure 13. Simulated radiation pattern of the Monopole Antenna on Rogers (RT/Duroid 5880tm)substrate of permittivity 2.2

indicating a peak boresight gain of 5.66dB under H plane at 3.5GHz as shown by marker m1.The radial axis represents the



indicating a peak boresight gain of 5.66dB under E plane at 3.5GHz as shown by marker m1.The radial axis represents the


-34.00

-28.00

-22.00

-16.00

-10.00

-4.00

2.00

90

60

30

0

-30

-60

-90

-120

-150

-180

150

120

HFSSDesign1h-plane3.5Ghz

m1

Curve Info


Name Ang Mag

m1 0.0000 5.6677

-36.50

-33.00

-29.50

-26.00

-22.50

-19.00

-15.50

-12.00

-8.50

-5.00

-1.50

2.00

90

60

30

0

-30

-60

-90

-120

-150

-180

150

120

HFSSDesign1e-plane 3.5GHz

m1

Curve Info


Name Ang Mag

m1 0.0000 5.6677



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Figure 15. Measured radiation pattern of the monopole antenna on Rogers (RT/Duroid substrate (5880tm)) and permittivity 2.2

indicating a peak bore sight gain of 5.75B under E plane at 3.5GHz, as shown by marker m1.The radial axis represents the Gain

(in dB) while the angular axis represents the scan angle( in degrees).


indicating a peak bore sight gain of 5.75dB under H plane at 3.5GHz, as shown by marker m1.The radial axis represents the Gain




12579


indicating a peak bore sight gain of 7.44dB under H plane at 2.4GHz, as shown by marker m1.The radial axis represents the Gain



indicating a peak bore sight gain of 7.62B under E plane at 2.4GHz, as shown by marker m1.The radial axis represents the Gain




12580

Table 1. Illustrating the comparison of the simulated & measured antenna parameters for Wi-Fi and the Wi-Max band using

Rogers(RT/Duroid 5880tm) substrate of 2.2 permittivity.

Sl

No

Antenna

parameters

Simulated Simulated Measured Measured

1 Resonant

Frequency

2.4GHz 3.5GHz 2.0GHz 3.66GHz

2 Return loss -35.27 dB -25.985dB -15.69dB -13.94dB

3 VSWR 1.08 1.12 1.48 1.52

4 Gain 7.49dB

( E&H)

5.66dB

(E &H)

7.44dB(H)

7.62dB(E)

5.75dB

(E&H)

5 Bandwidth 441MHz 557MHz 0.672GHz 1.25GHz

6 Frequency

range

2.172GHz to 2.614GHz 3.299GHz to

3.856GHz

1.7 GHz-2.37GHz 3.584 to 4.835GHz

7 Radiation

pattern

Figure of 8 under E plane and

Hemispherical under H plane

Nearly Omni directional

under E plane and H plane

Omni Directional Omni Directional

VI RESULTS AND DISCUSSIONS

From the Table 1, the simulated return loss values were close

to -35.27dB and -25.985dB in the lower and the upper

frequency bands respectively indicating that the antenna

radiates reasonably well in the Wi-Fi and the Wi-Max (3.5

GHz) frequency bands respectively. The simulated VSWR

values were below 1.5 signifying that the impedance matching

has been proper in Wi-Fi and Wi-Max frequency bands

respectively. The simulated and the measured gains agree

well. The structure resulted in a nearly omnidirectional

radiation pattern along the elevation plane and characterized

by the presence of nulls along the azimuth plane with a peak

boresight gain of 5.75dB in the Wi-Max band as shown in

Figure 15 and 16. While in the Wi-Fi band, the measured

radiation pattern were omni under E plane and characterized

by the presence of Nulls under H plane with a peak boresight

gain of 7.62dB.The simulated and the measured bandwidths

agree well. The measured bandwidths reported were 672MHz

and 1.25GHz for the lower and the upper frequency bands

respectively. The measured bandwidths were significantly

higher in the Wi-Max band when compared with the Wi-Fi

band.

Figure 19. Comparison of the simulation and measured results of various Antenna performance parameters such as Resonant

Frequency, Return Loss, VSWR, Gain and Bandwidth of the simulated and Fabricated Dual band Antenna resonating between

Wi-Fi(2.4GHz) and Wi-Max(3.5GHz).

-40

-35

-30

-25

-20

-15

-10

-5

0

5

10

Simulated Rogers 2.4GHz

Simulated Rogers 3.5GHz

Measured Rogers 2.4GHz

Measured Rogers 3.5GHz



12581

CONCLUSION

The simulated return loss values are close to -35.27 dB & -

25.985dB indicating that the antenna radiates more efficiently

in both the bands. The simulated vswr values are close to 1

in both the bands designed on Rogers indicating a good

impedance matching. The simulated and the measured Gains

agree well. The lowest reported Gain were 5.75dB in the

3.5GHz band while the highest reported value of the Gain

were 7.62dB under E plane at 2.4GHz.The total Gain

variation were in the range of 5.75dB to 7.62dB .The

measured gains were comparatively higher in the 2.4GHz

band when compared to 3.5GHz band. The measured

Bandwidths reported were 672MHz (Wi-Fi band) and

1.25GHz (Wi-Max band).The measured bandwidths were

significantly high in the Wi-Max band when compared to Wi-

Fi band. The measured radiation patterns were Omni

directional under E plane and characterized by the presence of

nulls under H plane with a peak boresight gain of 7.62dB in

the lower frequency band of interest.In the upper and the

pattern were Omni directional under E plane and associated

with nulls under H plane with a peak boresight gain of

5.75dB.

ACKNOWLEDGMENT

The Authors would like to Dr.Chandrika Sudheendra,Group

Director, ADE and Mr.Diptiman Biswas, Scientist ‘F”, ADE

for allowing us to use their facility for antenna

Characterization and radiation pattern measurement in the

Anechoic chamber.

REFERENCES

[1] S.A.Shah, M.F.Khan, S.Ullah,"Design and

measurement of Planar Monopole Antennas for

Multi-Band Wireless Applications”, IETE Journal of

Research, 2017.

[2] AdeelAfridi, SadiqUllah, ImadAli, ShahbazKhan,

James A Flint,"Design and Parametric Analysis of a

DualBandFrequency Reconfigurable Planar Dipole

Using a Dual Band Artificial Ground plane”, IETE

Journal of Research, Vol. 60, No. 1, Jan-Feb 2014.

[3] M.Z.M.Nor, S.K.A, Rahim, M.I.Sabran,

F.Malek,"Dual band, parabolic, slotted ground plane

directive antenna for WLAN Applications”, Journal

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No. 2, 2013.

[4] Li.Li, Shu-Hua. Rao, Bin.Tang and Ming-fu.Li, “A Novel Compact Dual-band Monopole Antenna using Defected Ground Structure”, 2013 International

Workshop on Microwave and Millimeter Wave

Circuits and System Technology

[5] Jacob Abraham, Thomaskutty Mathew, “Dual Band

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and WiMAX Applications”, Wireless Engineering

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[6] T. Wang, Y.Z. Yin, J. Yang, Y.L. Zhang, J. J. Xie,

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[7] Issam Zahraoui, Ahmed Errkik, Jamal Zbitou,

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“A New Design of a Microstrip Antenna With Modified Ground for DCS and WiMAX Applications”,International Journal Of Microwave

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[8] Z. Zakaria, N. A. Zainuddin, M. Z. A. Abd Aziz, M.

N. Husain, M. A. Mutalib “Dual-Band Monopole Antenna For Energy Harvesting System”, 2013 IEEE

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[9] S.M. Zhang, F.S. Zhang, W.M. Li, W.Z. Li, and H.Y.

Wu, “A multi-band monopole antenna with two different slots for WLAN and WIMAX applications”,

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[10] He Huang, Ying Liu , Shaoshuai Zhang, and Shuxi

Gong “Multiband Metamaterial-Loaded Monopole Antenna for WLAN/WiMAX Applications”, IEEE

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Documents

Design and analysis of a Dual band Monopole Antenna for ... · each other loaded with a partial ground plane. ... band monopole antenna using defected ground structure ... inverted-L