DESIGN AND ANALYSIS FOR X BAND VSAT APPLICATION MICROSTRIP PATCH ANTENNA AT

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DESIGN AND ANALYSIS FOR X BAND VSAT APPLICATION MICROSTRIP PATCH ANTENNA AT

7.5 GHZ

BY

NORALYA FATIN BINTI MUZAMIL

A dissertation submitted in fulfillment of the requirement for the degree of Master of Science (Communication Engineering)

Kulliyyah of Engineering

International Islamic University Malaysia

SEPTEMBER 2020

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ABSTRACT

In this research, a compact size and lightweight structure of rectangular microstrip patch antenna operating at 7.5 GHz is presented. This research is proposed to replace the existing parabolic reflector antenna for the VSAT application in terms of portability. The dimension of the proposed antenna is 19.00 mm × 30.55 mm which is compact in size. The simulation of microstrip patch antenna exhibits a good return loss, S11 of -42.09 dB, VSWR of 1.02 and gain of 7.18 dB by using CST Microwave Studio. The proposed antenna have been fabricated by using substrate RT/duroid ® High Frequency 5880 with dielectric of (𝜺_𝒓 = 𝟐. 𝟐, tan (𝜹) = 𝟎. 𝟎𝟎𝟎𝟗 and t = 1.575mm). Then, the measurement return loss of the antenna prototype is performed using a Vector Network Analyzer, while the radiation patterns are measured in the anechoic chamber. The measurement of the antenna prototype exhibit a return loss, S11 of -30.53 dB, bandwidth of 455MHz, gain of 3.88 dB and efficiency of 68.71%.

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ثحبلا ةصلاخ

،ةيامحلل يندعم ءاطغ اذ و لكشلا ليطتسم ،يلخاد يئاوه سردي ثحبلا اذه ددرتلا يف لمعي مجحلا ريغصو نزولا فيفخ 7.5

.زتريه اقيق

يئاوهلا اذه

لا تاقيبطت يف لكشلا ةرعقم ةسكاعلا تايئاوهلل لايدب نوكي نأ حرتقأ VSAT

حرتقملا يئاوهلا داعبأ .اهب ةنراقم همجح رغصو هنزو ةفخل 30.55mmx19mm

مجحلا ريغص وهو .

يئاوهلا نأ ةاكاحملا جئاتن ترهظأ

ةعجار ةراشا ةبسن هيدل حرتقملا loss)s11

(return

يلاوح ديج -

42.09

، dB ةقاطلا ةءافك لدعم و

VSWR هيدل

1.02 ( بسكلا و ، ) gain

يلاوح

7.18 مادختسإب جئاتنلا هذه تلجس دقو . dB .CST Microwave Studio

ص ئاوهلا عن ي

مادختساب حرتقملا RT/duroid

substrate

درتب ®

يلاع 5880 :ةيتلاا تافصاوملاب ةمدختسملا ةلزاعلا ةداملا ،

( Er=2.2 tan (δ)=0.0009 and t = 1.575mm )

ةصاخلا جئاتنلا تلجس

ةعجارلا ةراشلإا ةبسنب )

(return loss

للحم مادختسإب حرتقملا يئاوهلا جذومنل

جتم ةكبشلا تاه

Vector Network Analyzer تاهاجتإ سايق مت امك ؛

ةراشلإا radiation patterns

ةيسيطنغمورهكلا ةراشلإل ةلزاع ةفرغ يف

anechoic chamber ةراشلإا ةبسن :يلاتلاك حرتقملا يئاوهلا جذومن تاسايق .

ةعجارلا

- 30.53

ددرتلا قاطنو dB 455

،زتريهاقيم بسكلا

3.88

dB كلاو ةءاف 68.71 .%

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APPROVAL PAGE

I certify that I have supervised and read this study and that in my opinion, it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a dissertation for the degree of Master of Science (Communication Engineering).

………..

Sarah Yasmin Mohamad Supervisor

………..

Norun Farihah Bt. Abdul Malek Co-Supervisor

………..

Md. Rafiqul Islam Co-Supervisor

I certify that I have read this study and that in my opinion it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a dissertation for the degree of Master of Science (Communication Engineering).

………..

Khairayu bt Badron

………..

Farah Nadia bt Mohd Isa

This dissertation was submitted to the Department of Electrical and Computer Engineering and is accepted as a fulfilment of the requirement for the degree of Master of Science (Communication Engineering)

………..

Mohamed Hadi Habaebi

Head, Department of Electrical and Computer Engineering

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This dissertation was submitted to the Kulliyyah of Engineering and is accepted as a fulfilment of the requirement for the degree of Master of Science (Communication Engineering).

………..

Sany Izan Ihsan

Dean, Kulliyyah of Engineering

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DECLARATION

I hereby declare that this dissertation is the result of my own investigations, except where otherwise stated. I also declare that it has not been previously or concurrently submitted as a whole for any other degrees at IIUM or other institutions.

Noralya Fatin Binti Muzamil

Signature: ... Date: 30 September, 2020

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INTERNATIONAL ISLAMIC UNIVERSITY MALAYSIA

DECLARATION OF COPYRIGHT AND AFFIRMATION OF FAIR USE OF UNPUBLISHED RESEARCH

DESIGN AND ANALYSIS FOR X BAND VSAT APPLICATION MICROSTRIP PATCH ANTENNA AT 7.5 GHZ

I declare that the copyright holders of this dissertation are jointly owned by the student and IIUM.

No part of this unpublished research may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without prior written permission of the copyright holder except as provided below

1. Any material contained in or derived from this unpublished research may be used by others in their writing with due acknowledgement.

2. IIUM or its library will have the right to make and transmit copies (print or electronic) for institutional and academic purposes.

3. The IIUM library will have the right to make, store in a retrieved system and supply copies of this unpublished research if requested by other universities and research libraries.

By signing this form, I acknowledged that I have read and understand the IIUM Intellectual Property Right and Commercialization policy.

Affirmed by Noralya Fatin Binti Muzamil

……..……….. ………..

Signature Date

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ACKNOWLEDGEMENTS

Firstly, it is my utmost pleasure to dedicate this work to my dear parents and my family, who granted me the gift of their unwavering belief in my ability to accomplish this goal:

thank you for your support and patience.

I wish to express my appreciation and thanks to those who provided their time, effort and support for this project. To the members of my dissertation committee, thank you for sticking with me.

Finally, a special thanks to Dr Sarah Yasmin binti Mohamad for her continuous support, encouragement and leadership, and for that, I will be forever grateful.

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CHAPTER TWO: LITERATURE REVIEW………8

2.1 Overview………8

2.2 Antenna………..8

2.2.1 Antennas Performance Parameters. ………...9

2.2.1.1 Return Loss………..9

2.2.1.2 Voltage Standing Wave Standing Ration (VSWR)………10

2.2.1.3 Bandwidth………..11

2.2.1.4 Radiation Pattern………...11

2.2.1.5 Gain………....13

2.3 Classification of Antennas………...14

2.3.1 Parabolic Dish Antenna………....15

2.3.1.1 Double-Reflector Antenna………..…...15

2.3.1.2 Cassegrain Antenna………...16

2.3.1.3 Gregorian Antenna……….17

2.3.2 Microstrip patch antenna………..18

2.4 X BAND Communication………22

2.5 CST Microwave Studio Software ………23

2.6 Summarization of Previous Works………...24

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2.7 Summary………..28

CHAPTER THREE: RESEARCH METHODOLOGY……….29

3.1 Introduction……….29

3.2 Research Flowchart……….29

3.3 Design Architecture………30

3.3.1 Mathematical approximation to design microstrip patch antenna...30

3.3.2 CST Full wave modeling………..33

3.3.2.1 Design A (9.5GHz) ………...35

3.3.2.2 Design B (7.5GHz) ………...36

3.4 Design and Fabrication Processes Of The Prototype Antenna………...40

3.4.1 Convert from CST file into Gerber File………...41

3.4.2 Print layout from the Gerber File………...…..43

3.4.3 Cutting and profiling the substrate………...43

3.4.4 Printing the copper for the Interior Layers………...45

3.4.4.1 Preparation of board and Dry Film Photoresist………….45

3.4.4.2 Laminating of Dry Film Photoresist………..48

3.4.4.3 UV Exposer………...49

3.4.5 Etching Process………....51

3.5 Measurement Of Antenna………...55

3.5.1 Vector Network Analyzer (VNA) ………...55

3.5.2 Atenlab OTA-500………56

3.6 Summary……….63

CHAPTER FOUR: RESULTS AND ANALYSIS………..64

4.1 Introduction………64

4.2 Simulation Result of Antenna………64

4.2.1 Design A (9.5 GHz)………...65

4.2.2 Design B (7.5 GHz)………...69

4.3 Summary………77

CHAPTER FIVE: CONCLUSION AND FUTURE WORKS……….78

5.1 Conclusion……….…78

5.2 Future Works and Recommendations………...79

5.2.1 Design B (enhanced ground plane of 7.5 GHz) ………80

REFERENCES……….….84

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LIST OF TABLES

Table 2.2 Summary of Some Of The Related Works On Various Antennas 26 Design and Method in Satellite Communication

Table 3.1 Dimensions of the Microstrip Patch Antenna 32 Table 4.1 Overall performances of the simulated Design A (9.5 GHz)

microstrip patch antenna. 68

Table 4.2 Overall performances of Design B (7.5 GHz)

simulation, measurement and percentage difference between

simulation and measurement result of microstrip patch antenna. 77 Table 5.1 Overall performances of enhanced ground plane in

Design B (7.5 GHz) simulated microstrip patch antenna 83

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LIST OF FIGURES

Figure 1.1 Parabolic reflector antenna in STRIDE 3 Figure 2.1 Transition between transmitting and receiving antenna 9 Figure 2.2 a) Return loss b) Equations of return loss and

reflection coefficient 10

Figure 2.3 Directional radiation lobes and beam widths 12 Figure 2.4 a) Isotropic radiation pattern b) Omni-directional pattern 13

Figure 2.5 Cassegrain antenna 17

Figure 2.6 Gregorian Antenna 18

Figure 2.7 Regular patch antenna 19

Figure 2.8 a) Microstrip line technique, b) Coaxial Probe Feed,

c) Proximity coupled Feed and d) Aperture coupled feed 21

Figure 3.1 Flowchart of overall project 29

Figure 3.2 The fundamental setup for microstrip patch antenna by

using the CST-MWS 34

Figure 3.3 Parameters is defined 34

Figure 3.4 Full dimensions of Design A antenna 35 Figure 3.5 The dimension of Ground Plane is defined 36 Figure 3.6 The material used for Dielectric Substrate is defined 36 Figure 3.7 The dimension of Dielectric Substrate is defined 37 Figure 3.8 The dimension of Rectangular Patch is defined 37

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Figure 3.9 The dimension of Transformer is defined 38 Figure 3.10 The dimension of Feedline is defined 38

Figure 3.11 The dimension of Slots is defined 39

Figure 3.12 a) Full dimension on the designed antenna

b) Isometric view of the full designed microstrip antenna 39 Figure 3.13 Procedure of antenna fabrication process 40 Figure 3.14 Steps to convert the CST file to Gerber File 41 Figure 3.15 Printed antenna in a transparent sheet 43

Figure 3.16 CNC machine to cut the board 44

Figure 3.17 The exact dimensions of the antenna that need to be cut

using CNC machine 44

Figure 3.18 The CNC machine cut the board according to

antenna’s exact dimensions 45

Figure 3.19 The board surface is brushed to remove dirt 46 Figure 3.20 Preparation for Dry Film Photoresist 46 Figure 3.21 First layer of film is removed by using a “salotape” 47 Figure 3.22 The film was put into a white paper 47

Figure 3.23 Laminating process 48

Figure 3.24 Cut the unwanted laminate film 49

Figure 3.25 UV exposure machine 50

Figure 3.26 The board is place inside the UV exposure 50 Figure 3.27 Removing second layer of Film Photoresist 51 Figure 3.28 Glove and mask should be used before the

etching process for safety purpose. 52

Figure 3.29 Developer (-ve board) chemical 52

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Figure 3.30 Conveyorised spray machine 53

Figure 3.31 The antenna board put on top of bigger board 53

Figure 3.32 Stripper chemical 54

Figure 3.33 Completed antenna board fabrication. 54 Figure 3.34 The antenna board is measured using Vector Network analyzer 56 Figure 3.35 Anechoic Chamber in UiTM Shah Alam

for radiation pattern measurement of the antenna prototype 57 Figure 3.36 The antenna prototype in the antenna holder 58 Figure 3.37 Laser 1 marker is aligned to the center of the antenna holder 59

Figure 3.38 Interface Page for settings 59

Figure 3.39 Setting the frequency for radiation measurement pattern 60

Figure 3.40 Confirmation of setting the frequencies 61

Figure 3.41 Passive type choices 62

Figure 3.42 Save the measurements to specific folder 62 Figure 4.1 Design A microstrip patch antenna at 9.5 GHz 65 Figure 4.2 The simulated return loss of the Design A (9.5 GHz)

microstrip patch antenna 66

Figure 4.3 The simulated 3D Farfield Radiation Pattern from

isometric, y-axis and x-axis view of the Design A (9.5 GHz)

Figure 4.4 The polar farfield radiation pattern from E-plane of the simulated

Design A (9.5 GHz) microstrip patch antenna 67

Figure 4.5 The polar farfield radiation pattern from H-plane of the simulated Design A (9.5 GHz) microstrip patch antenna 67 Figure 4.6 The combination of polar farfield radiation pattern for E-plane and

H-plane of the simulated Design A (9.5 GHz)

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Figure 4.7 Design B microstrip patch antenna at 7.5 GHz 69 Figure 4.8 The (a) simulated and (b) measurement return loss of the

microstrip patch antenna for Design B (7.5 GHz) 70 Figure 4.9 The simulated VSWR of the microstrip patch antenna 71

Figure 4.10 The simulated 3D Farfield Radiation Pattern from (a) isometric, (b) y-axis and (c) x-axis view of the

Design B (7.5 GHz) microstrip patch antenna 72

Figure 4.11 The measured 3D Farfield Radiation Pattern from (a) below, (b) front and (c) top view of the

Design B (7.5 GHz) microstrip patch antenna 72

Figure 4.1 The (a) simulated and (b) measured polar farfield radiation pattern for E-plane from Design B (7.5 GHz)

Figure 4.13 The (a) simulated and (b) measured polar farfield radiation pattern for H-plane from Design B (7.5 GHz) microstrip patch antenna 74

Figure 4.14 The combination of (a) simulated and (b) measured polar farfield radiation pattern for E-plane and H-plane of the

simulated Design B (7.5 GHz) microstrip patch antenna 75

Figure 5.1 Enhanced ground plane for Design B microstrip

patch antenna at 7.5 GHz 80

Figure 5.2 The simulated return loss of the microstrip patch antenna

for enhanced ground plane of 7.5 GHz 81

Figure 5.3 The polar farfield radiation pattern from a) E-plane, b) H-plane and c) combination of E and H-plane of the simulated

microstrip patch antenna for enhanced ground plane of 7.5GHz 82

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LIST OF SYMBOLS

𝛤 Reflection Coefficient

∆𝐿 Correction Factor

𝜆_𝑔 Guide Wavelength

𝑍_𝑜 Impedance

𝜀_𝑟 Permittivity

𝜀_𝑒𝑓𝑓 Effective Dielectric constant

h Thickness of Substrate

t Metallization thickness

c Speed of Light

f Frequency

𝛿 Loss Tangent

W Width

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LIST OF ABBREVIATION

STRIDE Science Technolology Research Institute for Defence

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CHAPTER 1

INTRODUCTION

1.1 BACKGROUND OF THE STUDY

Nowadays as technology evolves in fast pace, antenna has become extremely important in communication technology. Thus, antenna plays a crucial aspect in this field because it transmits and/or receives electromagnetic waves with its specific direction and properties to the intended application (Balanis, 2016). There are various forms of antennas available in the market, for instances wire, aperture, microstrip patch, array, reflector and lens antennas (Ahmad, 2013).

Microstrip patch antenna is one of the most popular used antenna nowadays due to its excellent properties such as having low profile, a light and weight structure, low cost, ease of fabrication and ease of integration with circuits (Samsuzzaman & Islam, 2014).

Apart from that, patch antenna exhibits lower side lobes level which makes it a good antenna candidate for satellite applications. Lower side lobes level are crucial because there will be lower wasted radiation energy and will not cause interference (Cao, et al., 2018). In addition, a compact size antenna should be used for satellite application so that it can be easily carried around or accommodated on moving stations (Vivek, et al., 2015).

VSAT stands for ‘very small aperture terminal’ which has a diameter less than 2 metres (Madiawati & Suryana, 2016). Even though VSAT satellite communication is

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used more in military, VSAT also owns the benefits having a flexible configuration for satellite station, small size, less weight and low power consumption. Generally around the world, the frequency of military communication lies in between the X band range (8-12 GHz) (“Satellite frequency bands”, 2019). However, according to The Science &

Technology Research Institute For Defence in Malaysia (STRIDE), the range of military frequency used in Malaysia started at 7 GHz (Avl Technologies Operations And Maintenance Manual Model 1098 Fly Away Integrated Terminal System, 2019). The common antennas used for this specific application are parabolic reflector, microstrip, and array antennas.

In this project, a microstrip patch antenna is proposed to be used for VSAT application at frequency 7.5 GHz. The antenna should exhibit a compact size and a lightweight structure compared to parabolic reflector for mobility purpose. Figure 1.1 shows the existing parabolic reflector antenna used in STRIDE. The disadvantage of this type of antenna is that it is huge and heavy, which is not good for portability and cannot be used on a moving transport. The dimension of this antenna is around 46.0 inch x 29.3 inch x 13.5 inch (116.84 cm x 74.42 cm x 34.29 cm) with weight of 66.2kg (Avl Technologies Operations And Maintenance Manual Model 1098 Fly Away Integrated Terminal System, 2019). Therefore, it is expected that the proposed microstrip patch antenna can be an alternative solution to this problem.

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Figure 1.1: Parabolic reflector antenna used by STRIDE (Source: Avl Technologies Operations and Maintenance Manual Model 1098 Fly Away Integrated Terminal System,

2019) 1.2 PROBLEM STATEMENT

The most common antenna used in VSAT application is the parabolic reflector antenna (Madiawati & Suryana, 2016). However parabolic reflector antenna is too big and bulky to be conformed on a moving vehicle (Asci, et al., 2016). The evolution of military technologies nowadays requires an antenna that is not hefty, portable, easy to be carried around or accommodated on moving stations (Vivek et al., 2015). Even though parabolic reflector antenna is widely and commonly used, it is not compatible for military requirement in terms of portability. Hence, in this report, a microstrip patch antenna is proposed to fulfill this requirement where it can provide the advantages of having a lightweight, low profile and compact structure compared to the parabolic reflector.

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1.3

RESEARCH OBJECTIVES

The objectives of this research are:

1. To design, simulate and optimize a microstrip patch antenna for VSAT application in terms of having a compact size and a lightweight structure.

2. To fabricate the microstrip patch antenna.

3. To measure and compare the simulated and measured results of the microstrip patch antenna for validation purpose.

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1.4

RESEARCH METHODOLOGY

The research methodologies of this project are:

1. Performing research and literature review from books and previous papers such as journal publications and conference proceedings on the specific topic.

2. To complete objective 1, the design parameters of the microstrip patch antenna are studied and analyzed, followed by the simulation and optimization which are executed using CST Microwave Studio (CST MWS) software.

3. To complete objective 2, the design of the microstrip patch antenna is fabricated by using substrate RT/duroid® High Frequency 5880 at the antenna laboratory in International Islamic University Malaysia (IIUM)

4. To complete objective 3, the S11 measurement of the microstrip patch antenna is performed using Vector Network Analyzer, while the radiation pattern measurement is carried out in the anechoic chamber at Faculty of Electrical Engineering (FKE), Universiti Teknologi MARA (UiTM). The measurement results are then compared with the simulation results.

5. Report write-up and publication.

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1.5

RESEARCH SCOPE

There are five main scopes in this project which consist of design, simulation, optimization, fabrication and measurement. First of all, the design, simulation and optimization of the microstrip patch antenna is executed using CST Microwave Studio software (CST MWS). The antenna design is simulated to get the performance result such as gain, radiation pattern and return loss, S11. The antenna is also optimized in order to enhance the simulation results to fulfill the objectives of the project; which are to obtain a compact size antenna and a lightweight structure with good radiation performances. The antenna is then fabricated by using substrate RT/duroid ® High Frequency 5880 with dielectric of 𝜀_𝑟 = 2.2 , tangent loss of 𝜎 = 0.0009 and dielectric thickness of 𝑡 = 1.575𝑚𝑚. The S11 measurements of the antenna are performed using Vector Network Analyzer, while the radiation patterns are measured in the anechoic chamber. Finally, the comparison between the measurement results and the simulation results is performed.

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1.6

THESIS ORGANIZATION

Chapter 1 begins with the introduction of the report. A brief introduction on microstrip patch antenna and VSAT application are explained under Section 1.1, followed by problem statement and objectives of the project in Section 1.2 and Section 1.3. Next, the research methodology and the resources or tools used in this project are explained in Section 1.4 Finally, the scope of the project is explained in Section 1.5 to give a general idea on the area or subject matter that is being dealt in handling this project. Chapter 2 focused on the details, the theory of microstrip patch antenna and VSAT. The literature reviews on the topic are based on the articles, research paper, books and journal publication on the specific topic. Chapter 3 presents the detailed research methodology which is carried out in order to achieve the goals of the project. In chapter 4, the result and analysis for the proposed microstrip patch antenna is presented. The result and analysis of CST simulation and discussion is presented in simulation and graph form. The comparison between the measurement results and the simulation results is included. In this chapter also, fabrication and measurement of the microstrip patch antenna has included. In addition Chapter 5 concludes on the overall project. Future recommendation is also discussed in this chapter.

Kulliyyah of

DESIGN AND ANALYSIS FOR X BAND VSAT APPLICATION MICROSTRIP PATCH ANTENNA AT