Design, Fabrication and Performance Analysis of Microstrip … · and 5.08 to 5.97 GHz frequency bands while rejecting frequency ranges between these three bands. Next, a study was

International Journal of Electrical Electronics & Computer Science Engineering

Volume 1, Issue 5 (October 2014), ISSN : 2348 2273

Available Online at www.ijeecse.com

1

Design, Fabrication and Performance Analysis of Microstrip Antenna with MIMO

Implementation for Wireless Applications

Mohammad Ameen1, Mohammed Ismail. H

2

1P.G Scholar, Department of ECE, KMEA Engineering College, Ernakulam, Kerala, India. 2Assistant Professor, Department of ECE, KMEA Engineering College, Ernakulam, Kerala, India.

1 [email protected] , [email protected]

Abstract: This paper presents the design of a small and compact

size triple band Microstrip line feed slot antenna and their 2x1

MIMO implementation for Bluetooth, 4G LTE, WLAN, and

WiMAX applications. The proposed slot antenna consist of a

microstrip feed line on one side of the substrate, a ground plane

on another other side on which some slots are etched and some

L strips are added. Two S shaped parasitic elements are added

back to back on front side of the substrate. The simulation

results of the single antenna shows that the designed antenna is

capable of operating over 2.39 to 2.86 GHz, 3.13 to 3.68 GHz,

and 5.08 to 5.97 GHz frequency bands while rejecting frequency

ranges between these three bands. Next, a study was performed

to implement this antenna in 2x1 MIMO arrangement on the

same circuit space. The simulation results of the MIMO

antenna shows that it is suitable for working in Bluetooth, 4G

LTE, WLAN and WiMAX applications. Nearly Omnidirectional

radiation pattern, acceptable antenna gain, better mutual

coupling and better envelope correlation coefficient are

achieved over the three operating bands. The proposed antenna

is suitable for wireless communication systems.

Keywords: Multiple Input Multiple Output (MIMO); Wireless

Local Area Networks; Long Term Evolution; Worldwide Interoperability for Microwave Access.

I. INTRODUCTION

Presently the wireless communication is one of the fastest

growing segment of the communication field. There are

many commercial and government applications such as

Satellite communication, mobile radio, and Wireless communication where size, weight, cost, ease of

installation, performance, aerodynamics profile are major

constraints. The vision of the wireless communication

supporting information exchange between people and

devices is the communication frontier of the next few

decades. This vision will allow multimedia communication

from anywhere in the world. In the last few years, the

development of wireless local area networks (WLAN) and

WiMAX (Worldwide Interoperability for Microwave

Access), Bluetooth, 4G LTE (Long Term Evolution)

represented one of the principal interest in the information

and communication field. Also, in today’s environment, technology demands antennas which can operate on

different wireless bands and should have different features

like low cost, minimal weight, low profile and are capable

of maintaining high performance over a large spectrum of

frequencies.

In this era of next generation networks require high data rate and size of devices are getting smaller day by day. In

this evolution three important standards are 4G LTE, WiFi

(WLAN) and WiMAX. Wireless local area network

(WLAN) and WiMAX technology is most rapidly growing

area in the modern wireless communication. This gives

users the mobility to move around within a broad coverage

area and still be connected to the network [1-3]. This

provides greatly increased freedom and flexibility. For the

home user, wireless has become popular due to ease of installation, and location freedom. For success of all these

wireless applications we need efficient and small antenna

as the size of the device is becoming smaller and smaller.

This being the case, portable antenna technology has grown

along with mobile and cellular technologies. It is important

to have the best performance antenna for a device. The best

performance antenna will improve transmission and

reception, reduce power consumption, last longer and

improve marketability of the communication device [4-5].

II. ANTENNA DESIGN

Fig. 1. Dimensions of front side and ground plane (unit: mm).

The proposed antenna may be considered as a transformer

of the slot antenna. As shown in Fig. 1, the configuration of the triple-band slot antenna is designed and substrate with

FR4, relative permittivity of 4.4, and a loss tangent of 0.02.

The entire size of the antenna is only 30X30x3.2 mm3.

Without loss of generality, a 50Ώ microstrip feed line with

a width of 3 mm is given for centrally feeding the antenna

at one side of the substrate and two S shaped parasitic

mailto:[email protected]:[email protected]




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elements are added on one side of the substrate and Some

simple slots are etched on the ground plane to give all the

work bands.

Fig. 2.Configuration of the simulated antenna. (a) Case I. (b) Case II. (c) Case III (d) Case IV

The rectangular slot in the ground plane can get the lowest

resonant frequency of 2.52 GHz. There are some L shaped

strips are added on the ground plane to get the middle resonant frequency of 3.5 GHz. The addition of two slots

the S shaped symmetric parasitic elements provides the

highest resonance and makes impedance matching in the

wide band range. The L strips embedded on the rectangular

slot are used for feeding and providing the middle band

work.The initial length of slot embedded on the S shape

and L strip is approximated according to,

𝑙 = 𝜆𝑃4

= 𝑐

4𝑓 𝜀 , 𝜀 =

𝜀𝑟 + 1

2

where c is the speed of light in vacuum, f is the resonant

frequency, and εr is the relative permittivity of the

substrate.

The whole antenna is optimized with the commercial software CST Microwave studio and values of some

optimized parameters are shown in table 1.

Table I: Dimensions of Proposed Antenna

Parameters L W Lg Wg Wf Lf W1

Dimension 30 30 30 30 3 16 11.4

Parameters W3 W6 W7 W8 L6 L5 L3

Dimension 0.3 8.5 13 0.27 6 5.5 16.5

Parameters L2 L8 LG2 Lg3 Lg4 Lg5 Lg1

Dimension 4.57 4 2.25 2.75 2.75 1.5 5.75

Parameters Lg9 Lg7 Wg1 Wg2 Wg3 Wg5 G1

Dimension 6.75 11.25 11 4 8.1 8.1 0.5

Fig. 3. Frequency versus return loss plot of different stages of antenna.

The fig. 2 shows the various designing stages of the

proposed microstrip antenna and fig. 3 shows the

corresponding return loss plots. The simulated return loss

versus frequency curve for the designed single antenna is shown in Fig. 4. The designed antenna resonates at 2.52

GHz, 3.47 GHz and 5.68 GHz respectively. The return loss

for 2.52 GHz is -30.24 dB, for 3.47 GHz is -32.09 dB and

the return loss for 5.68 GHz is -27.10 dB which covers the

minimum required value of return loss of -10 dB. The

bandwidth of the proposed patch antenna is 470 MHz (2.39

GHz – 2.86 GHz), 550 MHz (3.13 GHz – 3.68 GHz) for

3.47 GHz and 900 MHz (5.08 GHz – 5.97 GHz) for 5.68

GHz.

Fig. 4. Simulated Return loss curve of the proposed antenna.




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Fig. 5. VSWR Plot of the proposed antenna.

The fig. 5 shows the simulated VSWR plot of the triple band antenna and VSWR ratio at 2.52 GHz, 3.47 GHz and

5.27 GHz frequency is 1:1.06, 1:1.05 and 1:1.09

respectively.

Fig. 6. Current distribution of the proposed antenna (a) 2.52 GHz, (b) 3.47 GHz and (c) 5.68 GHz

The current distribution at different frequencies are

illustrated in fig. 6(a), 6(b) and 6(c), The fig. 6(a) shows

that the current distributes mainly along the edges of the rectangular slot of the ground plane at 2.52 GHz. In figure

6(b) the current flowing along the two L strips embedded

in the ground plane at 3.47 GHz and in figure 6(c) the

current mainly concentrates in the slots provided in the

parasitic elements at 5.68 GHz.

III. INTEGRATION OF 2 x 1 MIMO ANTENNA

Fig.7 shows four common configurations of the

combination of two such antennas. The simulated S-

parameters of the MIMO/diversity configurations are

shown in Fig. 8. The proposed antenna provides good impedance matching with slight variation and high

isolation between the two antenna ports without the use of

any external slot. It is seen that in the front-to-front

configuration, the value of S12 is completely below the -

10dB while in the other configurations the S12 goes above

the -10dB.

Fig. 7. MIMO/diversity triple-band configurations, (a) front-to-front, (b) side by side, (c) orthogonal and (d) parallel.

Fig. 8 Simulated S-Parameters of different configurations of MIMO antenna

The simulated envelope correlation of the proposed

MIMO/ diversity triple-band configuration of the array

structures shown in Fig.7 is shown in Fig. 9. It is noticed

that all four configurations of the arrays, the front-to-front

provide less than 0.05 envelope correlations.

Fig. 9. Simulated ECC of different configurations of MIMO antenna.

IV. RESULTS AND DISCUSSION

(A) S- Parameters

Fig. 10. Simulated plots for the proposed MIMO antenna.

Examining the simulation results shown in Fig. 10, the return loss plots S11 and S22 are approximately same, the

mutual coupling S12 and S21 are same. The overall

reflection coefficient considering S11 and S22 of -10 dB

criteria. There is a multiband response happening at various

groups of frequencies. These bands are marked as band 1

(2.37 GHz – 2.76 GHz), band 2 (3.15 GHz – 3.67 GHz),

and band 3 (4.99 GHz – 5.97 GHz). The bandwidths for

these bands are determined by the reflection coefficient

(S11 and S22) of -10 dB or lower. The bandwidths are 400

MHz, 520 MHz, and 980 MHz of the three bands

respectively. In band 1 the S11 and S22 is -21.01 dB, band 2 at -31.06 dB and band 3 at -31.24 dB. In band 1 the mutual

coupling S12 and S21 is below -10.16 dB, band 2 at -13.70

dB and band 3 at -25.85 dB.




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(B) VSWR

Fig. 11. Simulated VSWR Plot of MIMO antenna.

Fig. 11 shows the VSWR plot for the MIMO antenna and provide VSWR of 1.19 for the lower band, 1.05 for the

middle band, and 1.05 for the upper band.

Radiation Pattern

Fig: 12, 13, 14 shows the simulated 3D radiation pattern, the radiation pattern seems to be nearly omni-directional.

Fig. 12. 3D Radiation Pattern (2.49 GHz)

Fig. 13. 3D Radiation Pattern (3.45 GHz)

Fig. 14. 3D Radiation Pattern at 5.66 GHz

(C) Envelope Correlation Coefficient

Fig. 15. Envelope correlation vs. frequency for MIMO.

The ideal value of Envelope correlation coefficient (ρ)

should be less than 0.07 for a mobile base station. Then for

mobile terminals, the value for ρ should be 0.5 or less.

From the fig. 15 the ECC will be less than 0.05 for all the

operating frequencies.

Table II: Comparison of Simulated Antennas

Antenna Type

Frequency

Range

Return Loss

Band

Width

Gain

Single

Antenna

2.39 GHz-2.86 GHz

-30.24 dB

470 MHz

2.66 dB

3.10 GHz-3.68 GHz

-32.09 dB

550 MHz

3.02 dB

5.08 GHz-5.96 GHz

-27.10 dB

900 MHz

4.09 dB

MIMO

Antenna

2.37 GHz-2.76 GHz

-21.01 dB

400 MHz

3.58 dB

3.15 GHz-3.67 GHz

-31.06 dB

520 MHz

4.22 dB

4.99 GHz-5.96 GHz

-31.24 dB

980 MHz

7.06 dB

Table III shows a comparison of fabricated triple band MIMO antenna and previously implemented triple band

MIMO antenna in [5-14]. The antennas designed in the

papers do not cover the WLAN (2.4/5.2/5.8),WiMAX

(2.5/3.5/5.5) and 2.6 GHz 4G LTE. The overall size of the

antenna reduced to 77 x 30 x 3.2 mm3 compared to the antennas designed in [5-14].

Table III: Comparison with Existing Mimo Antennas

Ref. No: Dimensions

(mm3)

WLAN

(2.4/5.2/5.8)

WIMAX

(2.5/3.5/5.5)

4G

LTE

(2.6)

[5] 80x18x1.6 mm3 (2.4/5.8) (2.5/3.5/5.5) -




5

[6] 85x40x0.64 mm3 (2.4/5.2) (3.5) -

[7] 110x52x1.6 mm3 (2.4) (3.5/5.5) -

[8] 48.54x40x1.6 mm3 (5.2) (3.5) -

[9] 110x52x1.6 mm3 (2.4) (3.5/5.5) -

[10] 110x160x0.8 mm3 (2.4) (2.5) (2.6)

[11] 99x55x1.6 mm3 (2.4) (3.5) -

[12] 125x85x0.8 mm3 (2.4) (5.5) -

[13] 79x160x1.52 mm3 (2.4/5.2/5.8) (3.5) -

[14] 40x90x0.79 mm3 (2.4) (3.5) -

MIMO

Antenna 77x30x3.2 mm

3 2.4/5.2/5.8) (2.5/3.5/5.5) (2.6)

The images of the fabricated single antenna and Multiple

input multiple output antenna for Bluetooth, 4G

LTE,WLAN and WiMAX applications is shown in fig. 16, fig. 17 and fig. 18. Fig. 19, Fig. 20, Fig. 21 shows the

comparison of simulated and measured results of single

antenna and Multiple input Multiple Output Antenna.

Fig. 16. Front view and Back view of fabricated SISO

Microstrip Antenna

Fig. 17 Front view of fabricated MIMO Microstrip Antenna

Fig. 18 Back view of fabricated MIMO Microstrip Antenna

Fig. 19. Simulated and Measured Return loss of the single antenna.

Fig. 20. Simulated and Measured Return loss of the MIMO antenna.

Fig. 21. Simulated and Measured Insertion loss of the MIMO antenna.

V. CONCLUSION

In this work a compact microstrip slot antenna designed for a triple band operation is presented. The proposed

antenna is composed of a ground plane on which a

rectangular slot is etched and a Pair of L strips embedded

in the slot and S shaped parasitic elements are added on

another side of the substrate that enables proper adjusting

of the resonant bands. The simulation results of the triple

band single antenna with bandwidths of 470 MHz (2.39

GHz - 2.86 GHz), 550 MHz (3.13 GHz - 3.68 GHz) and 900 MHz (5.08 GHz - 5.97 GHz) are obtained. Next, a

study was performed to implement the single antenna into

2x1 MIMO arrangements on the same circuit space. The




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simulation results of the MIMO antenna with bandwidths

of 400 MHz (2.37 GHz - 2.76 GHz), 520 MHz (3.15 GHz -

3.67 GHz) and 980 MHz (4.99 GHz - 5.96 GHz) are

obtained and it shows that the MIMO antenna is suitable

for working in Bluetooth (2.4GHz – 2.5 GHz), 4G LTE (2.5 GHz – 2.69 GHz), WLAN (2.4/5.2/5.8 GHz), and

WiMAX (2.5/3.5/5.5 GHz) applications. Because of the

good electromagnetic property and compact size, the

antenna is competitive candidate for multiband wireless

communication applications. The proposed antenna can be

an excellent choice for Bluetooth, 4G LTE, WLAN and

WiMAX applications due to its small size, simple

structure, good multi-band characteristics, nearly

omnidirectional radiation pattern, better gain, better mutual

coupling and better envelope correlation coefficient over

the three bands.

VI. REFERENCES

[1] Lin Dang, Zhen Ya Lei, Yong Jun Xie, Gao Li Ning, and Jun Fan, "A Compact Microstrip Slot Triple-Band

Antenna for WLAN/WiMAX Applications", IEEE

Antennas and Wireless Propagation Letters,

Vol.9.2010.

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

"Compact Triple-Band Antenna Using Defected

Ground Structure for WLAN/WIMAX Applications",

Progress In Electromagnetics Research Letters, Vol.

35,164, 2012.

[3] C.R. Byra Reddy, N.C. Easwar Reddy and C.S.

Sridhar, "A Compact Triple Band Rectangular

Microstrip Slot antenna for WLAN/WIMAX

applications", Journal of Theoretical and Applied

Information Technology, October 2011.

[4] Reza Karimian and Hamed Tadayon, "Multiband

MIMO Antenna System with Parasitic Elements for

WLAN and WiMAX Application", International

Journal of Antennas and Propagation, 2013.

[5] Ali Foudazi, Alireza Mallahzadeh, and Sajad

Mohammad Ali Nezhad, "A triple-band

WLAN/WiMAX printed monopole antenna for MIMO

applications", Microwave and Optical Technology

Letters, Vol. 54, No. 5, May 2012.

[6] A.R. Mallahzadeh, S.F. Seyyedrezaei, N.

Ghahvehchian, S. Mohammad ali nezhad and S.

Mallahzadeh,"Tri-Band Printed Monopole Antenna for

WLAN and WiMAX MIMO Systems", Proceedings of the 5th European Conference on antennas and

propagation.

[7] Masoumeh Darvish and Hamid Reza Hassani, "Quad

band CPW-fed monopole antenna for MIMO applications", EuCAP 2012.

[8] R. lothi Chitra, B. Ramesh Karthik and V. Nagarajan,

"Double L -Slot Microstrip Patch antenna array for

WiMAX and WLAN", IEEE, 2012.

[9] Masoumeh Darvish and Hamid Reza Hassani,

"Multiband Uniplanar Monopole Antenna for MIMO

Applications", 20th Iranian Conference on Electrical

Engineering, May 2012.

[10] Xing Zhao and Jaehoon Choi, "Multiband MIMO

antenna for 4G Mobile Terminal", Asia-Paci_c

Microwave Conference Proceedings, 2013.

[11] Teng Guo, Dongya Shen, Wenping Ren and Xiupu

Zhang,"A High Isolation MIMO Antenna for WLAN

and WiMAX", IEEE 2013.

[12] Sultan Shoaib, Imran Shoaib, Nosherwan Shoaib,

Xiaodong Chen and Clive G. Parini, "Design and

Performance Study of a Dual-Element Multiband

Printed Monopole Antenna Array for MIMO

Terminals", IEEE Antennas and Wireless Propagation

Letters, vol. 13, 2014.

[13] Reza Karimian, Homayoon Oraizi, Senior Member, IEEE, Saeed Fakhte, and Mohammad Farahani,

"Novel F-Shaped quad-band printed slot antenna for

WLAN and WiMAX MIMO Systems", IEEE

Antennas and wireless propagation letters, vol. 12,

2013.

[14] Chan Hwang See, Raed A. Abd-Alhameed, Zuhairiah Z. Abidin, Neil J. McEwan, and Peter S.

Excell,"Wideband Printed MIMO/Diversity Monopole

Antenna for WiFi/WiMAX Applications", IEEE

Transactions on Antenna and Propagation, vol. 60,

NO. 4, April 2012.

Documents

Design, Fabrication and Performance Analysis of Microstrip … · and 5.08 to 5.97 GHz frequency bands while rejecting frequency ranges between these three bands. Next, a study was