Design And Construction Of A Flexible TV Antenna

ABSTRACT

This paper presents the development of a flexible antenna for the digital television (DTV) reception in areas having poor signal or in high-rise buildings. The antenna structure is composed of a meander line printed on a polyimide film as a radiating element. It has a thickness of 0.3 mm, highly flexible, and very lightweight. The design and analysis of the radiating element are based on a full-wave method implemented by a commercial electromagnetic simulation software. The impedance matching between the radiating element, the feed line, and the active circuit are considered. Due to its flexibility, low profile, lightweight, and additional gain, the proposed antenna could be useful for various specific applications.

TABLE OF CONTENTS

 TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWLEDGEMENT

ABSTRACT

TABLE OF CONTENT

CHAPTER ONE

• INTRODUCTION
• BACKGROUND OF THE STUDY
• PROBLEM STATEMENT
• AIM AND OBJECTIVE OF THE PROJECT
• PURPOSE OF THE PROJECT
• SIGNIFICANCE OF THE PROJECT
• SCOPE AND LIMITATION OF THE PROJECT
• RESEARCH QUESTION

CHAPTER TWO

LITERATURE REVIEW

2.0     LITERATURE REVIEW
2.1      REVIEW OF TELEVISION BROADCAST
2.2     ANTENNA THEORY

CHAPTER THREE

3.0      METHODOLOGY

3.1     MATERIAL SELECTION

3.2     FABRICATION METHODS

CHAPTER FOUR

RESULT ANALYSIS

4.1   TEST

4.2   RESULT

4.3   APPLICATION OF FLEXIBLE ANTENNA

CHAPTER FIVE

5.0     CONCLUSIONS, RECOMMENDATION AND REFERENCES

• CONCLUSIONS
• RECOMMENDATION

5.2     REFERENCES

 

CHAPTER ONE

1.0                                                 INTRODUCTION

1.1                                    BACKGROUND OF THE STUDY

The first analogue television signals were broadcasted in 1956, and the analogue terrestrial network is today replaced by a digital terrestrial network (DTT), (Teracom, TV- och radioutsändningar, 2015). Teracom’s main role  is to ensure that program distributors, for example SVT, Barnkanalen and Kunskapskanalen, can reach their audience via a reliable, robust and cost-effective distribution. The television broadcast exists in the form of both free and paid-TV channels. Boxer Sweden and Denmark is the subsidiary that offers paid-TV channels, mainly via the terrestrial network but also via Internet.

To receive radio signals and watch television through the usage of DTT, households need to have a receiver antenna and a setup box. Television broadcast and receiver antennas are looking almost the same today, compared to 50 years ago. This is mainly because of the absence of improvement of network coverage and also due to lack of commercial incentives. When television broadcast went from analogue to digital in 2007, it was easier to keep customers by marketing the message “keep your old antenna, no changes are needed”. This has contributed to the decreased focus on developing TV-antennas and affected the usage of DTT Network.

To be able to receive radio signals and watch TV, the user needs to have a receiver antenna, inside or outside, and a setup box. The box can be a separate device from the TV or in form of a card, directly attached to the TV. The antenna is connected to a coaxial cable, which in turns is connected to a box inside the house. The box demodulates, deMUXes and decodes incoming data from the antenna. The output from the box contains a decompressed video, which is sent through an HDMI-cable to the TV. The TV receives the HDMI-signal and the user can thereafter watch TV. Which channels the user can watch are dependent of which subscriptions the user has.

Flexible electronics integrated with a textile substrate whose mechanical properties are able to bend, and twist would considerably offer many advantages in modern electronic devices. A wearable antenna for example can sense, communicate data, harvest energy, and function while being worn[1]. Recently, a lot of interest in wearable devices and antenna sensors in particular due to the simple configurations, sensing, multimodality, and low-cost fabrication [2]. The design of the antenna varies depending on the environment, frequency range, and transmission strength [3]. However, the performance of the antenna depends on the materials used. to design the antenna such as the substrate properties in terms of its ability to adapt to a harsh environment like bending and twisting, conductive materials in terms of resistance, and high tolerance to degradation due to mechanical deformation. In [4], the authors had design A circular antenna, aimed to measure the humidity content of sludge samples as a new method for determining the moisture content of dielectric materials. the wearable textile antenna becomes more involved in on-body applications, due to its ability to detect microstructure deformation and human motion and to monitor and supervise human health[5]. In a comparison with conventional antennas, textile antennas have the advantages of being integrated with the outfits and offer many key features such as lightweight, comfort, and washability. There are many different types of flexible antennas such as a microstrip patch antenna, monopole antenna, and planar inverted-F antenna. Conductive materials used such as gold, silver, and copper are widely used as a radiating element due to their high conductivity. High conductive materials ensure high gain, efficiency, and bandwidth. Silver, for example, had a conductivity of 6.173 × 107 (S/m). Another important consideration to design the flexible antenna is the substrate itself. Felt fabric[6], Jeans[7], and polyethylene terephthalate (PET)[8] are among many other substrates used due to low dielectric constant.

1.2                                          PROBLEM STATEMENT

Conventional  TV receiving antennas have large sizes and they are not rigid to where they are mounted (such as on top of TV sets). Furthermore, they are sensitive to only one polarization and, therefore, they have a poor indoor performance. Moreover, they are pure electric field antennas and, hence, their performance is significantly deteriorated in vicinity of conductive objects such as concrete walls. On the other hand, conventional indoor TV receiving antennas cannot be used in multi-input (MI) configurations and techniques for space and/or polarization diversity.

One of the critical barriers to technological advancements of next-generation IoT related devices is inflexibility stemming from form factor and weight considerations. While there have been orders of magnitudes of advances in miniaturization, flexibility is a feature that is hard to conquer. In order to overcome some of the above problems, flexible antenna have been developed which is often lightweight, portable, less expensive, environment friendly, and disposable (Zhan et al., 2014). Flexible electronic systems require the integration of flexible antennas operating in specific frequency bands to provide wireless connectivity, which is a necessity in today’s information-oriented society.

1.3     AIM AND OBJECTIVES OF THE STUDY

The main aim of the study is to build a flexible Antenna for Indoor Reception of UHF Terrestrial Digital TV Broadcasting. The objectives of the study are:

1. To build a flexible, lightweight, portable, less expensive, environment friendly, and disposable antenna.
2. To improve the reception of a television

• To increase the performance of a television set

1.4     PURPOSE OF THE STUDY

The purpose of this work is to develop a new concept for a future digital TV-antenna thereby improving a television reception.

1.5     SIGNIFICANCE OF THE STUDY

Flexible antenna will serve a means of improving digital television reception for people living at a distance at least 20 km from the nearest transmitter mast. From this distance, flexible antennas are normally required.

To the student involved, this study will serve as means of having a wider knowledge about antenna and it theory.

1.6     SCOPE AND LIMITATION OF THE STUDY

The scope of this work covers building a flexible antennas which can be fabricated using nanoparticle inks, silver-nanoparticle inks, thin glasses, textile materials, metal foils, conductive polymers, graphene, plastics, or polymer substrates. The chosen substrate material must withstand mechanical deformations such as bending and twisting.

The mechanical properties of the rubber makes the antenna flexible. The antenna operates in the ISM band(2.4–2.5) GHz.

Due to lack of time and knowledge within the area electrical engineering and wireless communications, limitations needed to be concretized in order to have a manageable project and achieve a master thesis within the area Industrial Design Engineering. Decisions are made not to focus on designing a new technology for a TV-antenna, instead base the final solution on an already existing technology and develop it in the meaning of design and construction. The antenna will be designed to suit the UHF band and not the VHF band.

1.7     RESEARCH QUESTION

1. What is a flexible antenna?
2. What makes the antenna flexible