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In this paper, the influence of user’s hand on mobile terminal antenna when it placed approximately on top of Multiple Input Multiple Output radiating element antennas (PIFAs) is studied extensively. The antenna is designed to operate at 5 GHz with 1.5 GHz of -6 dB bandwidth. The effect of user’s hand with different finger positions are studied at seven positions on slit at the ground plane, seven differences height above the antenna and nine different locations around the radiating element at 2 mm height from antenna. The losses due to presence of hand are studied in terms of scattering parameters, radiation efficiency and matching efficiency. The maximum loss in term of isolation in the presence of user’s hand is found at 6 mm on the slit and it decreased as the hand move away from the slitted area on the ground plane. The maximum efficiency loss is observed when the finger is placed right on top of the radiating element with -5.85 dB compare to antenna without the presence of user’s hand. On the other hand, the result for matching efficiency indicates approximately 0.2 dB losses occurred when the fingers are varied at different height and position.

Ultra-wideband (UWB) radio is a fast-emerging technology with many unique attractive features that promotes major advances in wireless communications, networking, radar, imaging, and positioning systems. Here, we propose a microstrip antenna with an ultra-wideband frequency. Because of the round corner of the rectangular slot and partial rectangular patch, the bandwidth of the antenna is enhanced largely. Good agreement between the measurement and simulation has been achieved. To validate the simulation results, prototypes of the proposed antenna are fabricated and tested. Measured results show a good agreement with simulated results. The prototype with overall size of 138 mm × 40 mm achieves good impedance matching, constant gain, and stable radiation patterns. The impedance bandwidth of the antenna reaches up from 600 MHz to 6.0 GHz for S11. Meanwhile, a good omnidirectional radiation performance has also been achieved.

The design of a wearable wideband textile antenna based on a loop structure and fed using a coplanar waveguide line is proposed in this work. Characteristic mode analysis is used to first estimate the radiating modes on the structure. This is to ensure that the optimal mode significance is chosen. Analysis of modal significance enabled the first four modes to be identified from the structure. In this paper, the antenna is proposed to designed with an inverse partial ground (IPG) to enhance the bandwidth. It is shown that this IPG method improved impedance bandwidth to 1560 MHz (60.57%), indicating a bandwidth broadening of about 370 MHz (11.61%). A compact size of 70×70 mm2(0.57 × 0.57 λg) is also maintained, with a realized gain of 4.23 dBi. Finally, the proposed antenna is fabricated and measured to validate the analysis experimentally, indicating a good agreement with simulations.

Wireless connectivity is a critical enabler for many IoT applications. Antennas are often required to be installed inside the device cover, which usually occurs in small sizes with optimal performance. On the other hand, a suitable antenna should also have high efficiency, gain and adequate bandwidth covering the desired frequency range. Here, we proposed new type of Frequency Selective Surface (FSS) with miniaturized resonator element to enhance the gain of an CPW antenna. Furthermore, the miniaturization of the Frequency Selective Surface unit cell is attained by coupling the two meandered wire resonators. The wire resonator is separated by thin and single substrate layer. The structure of the FSS is shown to have a FSS unit cell dimension that is miniaturized to 0.057λ. The CPW antenna size is only 28.8mm × 46.5mm operating at 2.45 GHz frequency. With the additional of the FSS, the antenna’s gain reaches up from 1.8 dBi to 2.6 dBi with omnidirectional radiation pattern.

In this paper, the influence of user’s hand on mobile terminal antenna when it placed approximately on top of Multiple Input Multiple Output radiating element antennas (PIFAs) is studied extensively. The antenna is designed to operate at 5 GHz with 1.5 GHz of -6 dB bandwidth. The effect of user’s hand with different finger positions are studied at seven positions on slit at the ground plane, seven differences height above the antenna and nine different locations around the radiating element at 2 mm height from antenna. The losses due to presence of hand are studied in terms of scattering parameters, radiation efficiency and matching efficiency. The maximum loss in term of isolation in the presence of user’s hand is found at 6 mm on the slit and it decreased as the hand move away from the slitted area on the ground plane. The maximum efficiency loss is observed when the finger is placed right on top of the radiating element with -5.85 dB compare to antenna without the presence of user’s hand. On the other hand, the result for matching efficiency indicates approximately 0.2 dB losses occurred when the fingers are varied at different height and position.

Device-Free Localization (DfL) exploits the radio signal irregularities, hence can be used as an assistive technology to detect the moving entities, e.g. people, without the need for wearable devices. However, most of DfL systems employ omni-directional antennas, where the localization accuracy of these systems experienced the complex multipath propagation behavior. The directional micro-strip patch antennas have been implemented into the existing DfL system to observe the quality of radio link behavior and its effect to the human indoor localization accuracy. The performance of the proposed system has been evaluated and compared to the existing omni-directional attenuation-based DfL, which usually experienced the complex multipath propagation problem. Result shows that the proposed system was able to accurately detect a human presence in both static and moving scenarios, with a significant improvement in the quality of radio links behavior.

An Ultra-wideband (UWB) radio is a fast-emerging technology. It is offering several unique attractive features that promotes major advances in wireless communications, networking, imaging, radar and positioning systems. Here, an Ultra-Wideband Coplanar Waveguide fed Monopole antenna for IoT Applications is proposed. The bandwidth of the antenna is enhanced due to the partial rectangular patch and the round corner of the rectangular slot. To validate the simulation results, prototypes of the proposed antenna are fabricated and tested. Based on the results, good agreement has been achieved between the measurement and simulation. The antenna prototype with a total size of 138 mm × 40 mm achieves good impedance matching, constant gain and stable radiation patterns. The impedance bandwidth of the antenna reaches up from 600 MHz to 6.0 GHz for S11 with good omnidirectional radiation performance has also been achieved.

In the air, there are many dust particles and pollutant gases such as carbon dioxide and carbon monoxide that created an air pollution. The indoor and outdoor air pollution has brought the illness and harmful effect to human health. This creates a need for an IoT Alarm Air Quality Monitoring System to detect the dust particle, pollutant gases, temperature and humidity in the surrounding. The objective of this research work is to develop an indoor and outdoor air quality monitoring system for different air quality parameters (carbon dioxide and carbon monoxide), temperature, humidity, and dust concentration (air particle). Besides, the Node-RED dashboard and Android app are developed for real-time remotely applications in this system. The system performance is evaluated by testing the sensor used in the research work. In this research work, NodeMCU, MQ7, MQ135, DHT22, and DSM501A are mainly used to develop the hardware. The MQTT is implemented as publish-subscribe network protocol to transfer the data as a message with the specific topic name. In the MQTT, the Node-RED dashboard, Android app and hardware are the MQTT client which are able to publish and subscribe the message. The Node-RED dashboard acts as a live dashboard for monitoring and alarming purpose whilst the Android Studio is used to develop an Android app for the monitoring and alarm system in the smartphone. The Node-RED dashboard and Android app are able to display the data and notification message for different parameters on healthy or unhealthy level. The user can activate and deactivate the alarm system in the Node-RED dashboard or Android app as well.

In the current trend, machine learning has been used widely for network attack detection. The performance of a machine learning model depends on its training dataset and the dataset distribution. Network attack detection is one of the problems that usually suffer from the imbalanced data distribution. However, the effect of this imbalanced data is generally neglected by researchers. Therefore, in this research, we studied the impact of an imbalanced multiclass dataset to the machine learning performance. Five state-of-the-art machine learning algorithms were used in this study, and the classifiers that can classify the minority class or the majority class instances accurately were also identified. In this research, the performances of these classifiers were evaluated by using the performance metrics: true positive rate, false positive rate, precision, F-measure, ROC area, and classification accuracy. The results show that the J48 classifier outperforms the other four classifiers in every aspect. Besides, Naïve Bayes, J48, has also worked as the best classifier that able to classifies the instances of the minority class accurately.

In this paper, Circular patch antenna design with defected ground plane is designed. The antenna is designed with circular patch and defected ground plane to allow it to operate in lower frequency as well as improved the antenna gain. The antenna has a feeding port and two defected ground slots to affect the frequency of the antenna. The proposed antenna is designed and simulated using Computer Simulation Technology (CST) Studio Suite 2016. The designed antenna has an operating frequency of 2.42GHz. A prototype has been fabricated and tested using network analyser and the measured results are in a good agreement with simulations.

Laundry Management System and Laundry-On-Demand Mobile Applications are presented in this paper. Using conventional laundry service method, customer is not informed about the laundry process stage, does not have option to arrange the preferred laundry pick up time for the deliveryman to pick up the unwashed laundry from the address provided by customer and the laundry ordering paper forms are often lost in transit between customer and admin. Therefore, a laundry management system software and laundry on demand mobile application is demanded to solve the problems. The software development is performed using an open source developing platform Android Studio IDE and Firebase Real-time Database, Authentication, Cloud Messaging and Cloud Storage. The method used to develop the software is waterfall modelling and two characters are involved, which is admin and customer. The two characters functions are separated in two different applications. A Laundry Management System Software is developed for admin to manage, make order and monitor the business. A Laundry-On-Demand Mobile Application is developed for customer to make order and monitor the order. These both applications can receive notification from each other. The data can be correctly written and read from Firebase Real-time database, Firebase Authentication, Firebase Cloud Storage. The developed software and mobile application are evaluated in term of its functionality.

The ability to have a communication with devices implanted inside a human body will cause a great improvement in current wireless medical applications technology. Wireless Capsule Endoscopy (WCE) is a medical device that could send images from inside of human’s intestines to the sensor outside the body. However, this device has few disadvantages like its location cannot be detected once it entered the body and it also cannot be control from outside the body. Considering these factors, an antenna that has the ability to penetrate into human body tissues for in-body communication is proposed. UWB system has considered as the solution for future in-body communication devices since current standard does not allow high data rate wireless connections between implanted nodes. Low part of UWB frequency band which is 3.1 GHz to 5.0 GHz is used in this research in order to reduce the attenuation through the body tissues as the frequency increase. The design of this antenna has taken in consideration of the propagation medium which is the human body tissues. Simulation for the designed antenna was done in CST Software. The size of this antenna is designed to be compact and wearable on human body. The substrate used for this antenna is cotton to ensure comfort once it is placed on the human body. The results that are considered in this research are the S11, directivity and gain of the antenna. Both simulation results and measured results are compared to evaluate the ability of this antenna.

This project is focused on the development of personal shopper mobile phone application. The purpose of this system is to help part-timer and full-timer personal shoppers gather in one platform and also for the customer to hire a personal shopper to buys their items. This project will implement a rating system, give reward to the customer, accept customer requests, view customer requested details and contact the customer through Whatsapp application. This application is very flexible for the customer and personal shopper where the customer can become a personal shopper and vice versa. This entire project is developed according to software engineering methodology with the waterfall model. The tool used to create this project is Android Studio with Java, PHP, XAMPP Server, and MySQL database.

A compact square-shaped circularly polarized antenna is presented for pico-satellite application. Four dipole antennas are integrated with a phase delay line on a Rogers RO4003C to operate at 2.4 GHz with a dimension of 0.724λ g (55mm) × 0.724λ g (55mm) × 0.0112λ g (0.85mm) based on the lowest guided wavelength. Reflection and radiation performance exhibited are acceptable, with an impedance bandwidth and axial ratio bandwidth of 34 % and 11 % respectively. The proposed antenna operates in circular polarization with a maximum gain of 3.49 dB towards the forward direction.

In this paper microstrip triangle with slot antenna for 5G wireless communication network are proposed. The microstip triangle antenna is design and operating 60 GHz milimeter-wave frequency band and it's suitable for 5G wireless communication. The substrates are chosen in the design, which are RogerRT5880 with copper thickness 0.035 mm to analyze their effect toward milimeter-wave performance on the designed. The designed and analysis is performed by using CST Microwave Studio. The lowest return loss of the antenna is -24.75dB which is triangle with slot and the maximum gain obtained is 6.82 db at the 59.68GHz for this antenna. The antenna is considering the gain, return loss and size, the microstrip antenna can be a suitable candidate for the 5G wireless application for short range high speed communication.

The antenna application for internet of things (IoT) in urban infrastructure is introduced. Here, an effective design of microstrip 3D antenna for a RFID system in IOT which can also be used in narrow-band wireless communication is proposed. The antenna is combination of meander line techniques implemented with 3D structure resulted to miniature size of antenna that will be useful in many application. The critical parameters analysis and simulation results demonstrate the validity of the antenna with high gain and impedance matching are discussed as well.

User interaction (UI) has been identified to degrade the performance of the antenna. A system that measures impedance characteristics of a planar inverted-F antenna (PIFA) when there are user interactions is designed using Keysight VEE Pro. The operational frequencies of the antenna are 900 MHz and 1800 MHz at low band and high band, respectively. The obtained results are compared and then a new impedance matching circuit is proposed and designed by using ADS (Advanced Design System). The proposed matching circuit at each operating frequency is a basic lumped circuit using the L network. Both simulation and experimental work have been done.

The use of energy saving glass has become very popular in the modern day building design. This energy saving property is achieved by applying a very thin tin oxide (SnO2) coating on one side of the glass. This coating can provide good thermal insulation to the buildings by blocking infrared rays while being transparent to visible part of the spectrum. Drawbacks of these energy saving windows is that it also attenuates the transmission of useful microwave signals through them. These signals fall within the frequency band of 0.8GHz to 2.2GHz. In order to pass these signals through the coated glass, the use of aperture type frequency selective surface (FSS) has being proposed. In the present work, SnO2 thin film with FSS structure was fabricated. Microwave transmission through SnO2 coated glass with FSS structure was also analyzed using network analyzer. The result of computer simulation was confirmed and consistent with the network analyzer results that showed the improvement of SnO2 coated glass with the FSS structure.

Structural health monitoring (SHM) technologies have attained attention to monitor civil structures. SHM sensor systems have been used in various civil structures such as bridges, buildings, tunnels and so on. However the previous sensor for SHM is wired and encounter with problem to cover large areas. Therefore, wireless sensor was introduced for SHM to reduce network connecting problem. Wireless sensors for Structural Health monitoring are new technology and have many advantages to overcome the drawback of conventional and wired sensor. This project proposed passive wireless SHM sensor using frequency selective surface (FSS) as an alternative to conventional sensors. The electromagnetic wave characteristic of FSS will change by geometrical changes of FSS due to mechanical strain or structural failure. The changes feature is used as a sensing function without any connecting wires. Two type of design which are circular ring and square loop along with the transmission and reflection characteristics of SHM using FSS were discussed in this project. A simulation process has shown that incident angle characteristics can be use as a data for SHM application.

The capability of the flexible substrate of the frequency selective surface (FSS) to filter out particular frequency is discussed in this paper. A new type of FSS are applied using flexible thin plastic substrate to enhance the performance of the conventional FSS that lacks of flexibility and cannot be used in bending surface. A simulation based investigation shows that the diameter or length of the square has a significant effect on the band-stop selective characteristic of the FSS. The frequency response of the band-stop are at 2.45GHz that drop at -10dB.

The design of directive antenna using Frequency Selective Surface (FSS) superstrate is proposed in this project. The suitable design FSS as superstrate layer is very important to enhance the high directivity and narrow bandwidth on the antenna. By using the FSS layer to design the superstrate layer, there are able to determine the reflection coefficient accordingly to the desired frequency.

This paper is introduced a passive sensor to detect the performance of the structure using three-dimensional (3D) Frequency Selective Surfaces (FSS). The proposed 3D Circular FSS results are proved behave as passive sensor with changing of sensitivity incident angles to be apply in Structural Health Monitoring (SHM) system. Moreover, this 3D Circular FSS capable to operate without stand to any (DC/AC) power and very low cost in term of installation and maintenance.

Fibre Bragg Grating is an optical fibre that widely use as sensor to sense strain, temperature and pressure. The advantages of FBG sensor are it will not affected by electromagnetic interference which can improve the accuracy of the result and also can be wearable sensor. In this paper, Optisystem software tools are used to analyse the strain performance of FBG sensor for monitoring knee joint movement in rehabilitation process. Single mode FBG with original wavelength of 1550nm are used to get the accurate result because of less attenuation and absorption factor. This project also analysed the wavelength shifted when strain experienced by FBG change. The accuracy of sensor and method of delivering the result are taken into the account. The interrogator are used to display the wavelength shifted by the FBG when there is change in strain experienced by FBG. All of the proposed designed are tested by using simulation software and the wavelength shifted in the simulation are compared to the theoretical value that has been calculated in this project. The development of this system expected to improve the rehabilitation process towards a healthy life.

Optical millimeter-wave signal generation in Radio over Fiber (RoF) based on external modulators using different modulation schemes such as Single-Sideband (SSB), Double-Sideband (DSB) are experimentally compared. The major fallout for external modulation scheme system performance to downgrade is due to dispersion and the fading effect in optical signal generation while generating high Bit Error Rate (BER) when involving long distance delivery. In this work, we proposed mm-wave signal utilize Stimulated Brillouin Scattering (SBS) scheme which indicates the best performance amongst the scheme based on simulation that it achieves to propagate longest of distance over fiber, highest receiver sensitivity, the lowest BER and coherence of Mach-Zehnder Modulator (MZM) extinction ratio. Mm-wave signal of 40 Ghz and 10 Gb/s data rate was generated with the plotting of eye diagram.

This paper presents a new class of Sequential Algorithm (SeQ) code for Optical Code Division Multiple Access (OCDMA) system. The SeQ code has advantages of various cross – correlation property at any given number of users, and code weights. The result shown, at error floor BER = 10-09, the SeQ code capability to support 190 numbers of simultaneous users was higher than those achieved by FCC (W=4), DCS (W=4) and MFH (W=4). SeQ code excellently support 190 number of users due to due to the arrangement of code algorithm and flexibility cross-correlation (0 and 1) role. In addition, SeQ code capable to support up to 70 km for bit rate 155 Mbps in comparison 622 Mbps, 1 Gbps, and 2 Gbps be able to support 40km, 30km and 20km respectively. Hence, we can ascertain that PIIN and MAI are successfully eliminated for SAC-OCDMA coding system.

A new type of Frequency Selective Surface (FSS) with miniaturized resonator element is proposed. The FSS structure is shown to have a FSS unit cell dimension that is miniaturized to 0.067 $\lambda_{{{0}}}$ . Miniaturization of the FSS unit cell is achieved by coupling two meandered wire resonators separated by single thin substrate layer. The capacitance due to the small separation between the meandered wire elements results in a lowering of the resonant frequency. To demonstrate the validity of the design, the meandered wire resonator FSS was fabricated and tested using a free space measurement facility. The FSS produces a stable angular response up to 80 degrees for TE and TM incident angles.

Reconfigurable and tunable frequency selective surfaces (FSSs) are of significant interest in applications such as tunable radomes and adaptive screening of unwanted wireless transmissions. Conventional FSSs require additional bias circuitry to tune the operating frequency or to change its characteristics. In this letter, a new tuning technique using a spring resonator element is proposed. This technique can be applied to FSS design to make it reconfigurable and/or to fine-tune the response. The FSS frequency response can be adjusted by changing the spring height $h$ with applied pressure. The functional characteristic of the FSS can also be altered between a bandstop and bandpass filter response. A parametric analysis of the novel spring FSS is undertaken in CST software, and the results are validated with experimental measurement .

IoT technology has improved the quality of life as well as provides intelligence and comforts to the user. A Wireless Sensor Networks (WSN) technology is one of the powerful technologies that enable IoT objects to communicate with each other. Device-Free Localization (DFL) system exploits changes in radio signals across different environments aims to detect and track entities without requiring them to carry any additional RF devices or to be cooperatively participating with the localization process. This paper proposes a received signal strength indicator (RSSI) — based DFL system that can be used to detect human presence in an area of interest (AoI) using changes in signal strength measurements. The main objective of this paper is to design a DFL system that can be easily deployed and configured using IRIS mote from MEMSIC based on ‘plug and play’ concept and operates in real time. The system is deployed in CEASTech's Research Room by using the IRIS mote as the communication module in the network. The principle behind this is that the human body and motion have strong impact on the signal strength of indoor wireless links being transmitted from a transmitter to one or more base stations by either shadowing or diffraction, or by scattering. Result shows that signal strength fluctuate by 3.97dBm and from 10 to 15dBm with the presence of stationary human and moving human respectively.

In this paper, a new FSPA for new application — outdoor RF energy harvesting will proposed and designed. A new FSPA structure will joint with folded patch meander line and two pairs of slot embedded into its ground plane. A less profile, less cost and ease to fabricate the folded shorted patch antenna (FSPA) will introduced. The proposed antenna designing and performing using Computer Simulation Technology (CST). Simulated results show that this antenna can obtain an impedance bandwidth of 2.48% from 839 to 860 MHz at the center frequency of 848 Mhz. The results also show that the good omnidirectional radiation pattern and stable gain over the operating frequencies.

This paper describes the design procedure of a deployable antenna for Cubesat applications operating in the UHF frequency band of 437 MHz. Due to the expected large size for operation in this band, the meanderline and Vivaldi miniaturization and broadbanding techniques are used to obtain a wider impedance bandwidth. This is to ensure the size compatibility of the proposed antenna to the compact Cubesat chassis, and to ensure operation with different orientations in space. The antenna is designed using CST Microwave Studio software, and is aimed to be integrated with the RF components in the Cubesat platform. The antenna is capable of operating in the 437 MHz band with a 10 dB impedance bandwidth of 5% and a gain of 4.1dBi.

This paper introduced a new type of passive sensor without using any power consumption for Structural Health Monitoring (SHM) system. The 3D FSS will be used as new type of passive sensor to replace current sensor technology. This new 3D FSS design was modified from the basic square cross section unit elements by adding extra height on conductor element. By elevating conductor elements of square cross section, the transmittance FSS meet the appropriate results that will be used in SHM. Another important characteristic of the FSS is the sensitivity towards incident angle, where up to 80 degrees incident angle TE and TM incident wave are studied. The influence of various main parameters to design 3D FSS characteristic was investigated using CST software simulation tools.

Influence of hand on the MIMO antenna performance for future 5G terminal has been studied and presented in this paper. The study covers on performance for mobile terminal operating at 5.0 GHz with 1 GHz bandwidth at −6 dB. Development of this study is due to the concern from service provider and mobile designer in developing a small and compact mobile terminal. The effect of users finger is studied on sixteen index finger locations. Depends on the location of the index finger, the reflection coefficient and mutual coupling are deteriorated, whereas radiation and mismatch efficiency losses are increased. It is shown that the losses of radiation and mismatch efficiencies can be up to −1.6 dB and −0.9 dB respectively.

A novel 3D Frequency Selective Surface (FSS) architecture based on a circular ring unit element is presented. The circular ring was made 3D by creating a cylindrical element of a certain length, adding an extra degree of freedom into the structure. The length of the cylinder is shown through electromagnetic simulation to have a signiflcant efiect on the frequency characteristics of the FSS. Increasing the length of the cylinder can change the FSS from a band-stop to a band-pass fllter response. The center frequency of both band pass and band stop responses can also be tuned with adjustment to the length. Dielectric materials are introduced in the center of the cylindrical unit cell elements to simultaneously obtain a stop and pass band with a sharp transition. For high dielectric fllling materials, the 3D periodic structure exhibits negative refractive index metamaterial properties. A parametric analysis was conducted on these new cylindrical unit elements, and a prototype 3D FSS structure has been constructed and experimentally validated.

This paper presents the design of circularly polarized printed slot antenna operating at 5 – 6 GHz. The proposed antenna consists of L-shaped feedline on the top of structure and circular ring slot positioned at the ground plane underneath the substrate as a radiator. A radial and narrow slot in the ground plane provides coupling between the L-shaped feedline and circular ring slot. The circular polarization is realized by implementing the slits perturbation located diagonally to perturb the current flow on the slot structure. The antenna prototype is fabricated on FR4 substrate. The simulated and measured results are compared and analyzed to demonstrate the performance of the antenna. Good measured of simulated results are obtained at the targeted operating frequency. The simulated -10dB reflection coefficient bandwidths and axial ratio are 750 MHz and 165 MHz, respectively. The investigation on the affect of the important parameters towards the reflection coefficient and axial are also presented. The proposed antenna is highly potential to be used for wireless local area network (WLAN) and wireless power transfer (WPT).

Structural health monitoring (SHM) technologies have attained attention to monitor civil structures. SHM sensor systems have been used in various civil structures such as bridges, buildings, tunnels and so on. However the previous sensor for SHM is wired and encounter with problem to cover large areas. Therefore, wireless sensor was introduced for SHM to reduce network connecting problem. Wireless sensors for Structural Health monitoring are new technology and have many advantages to overcome the drawback of conventional and wired sensor. This project proposed passive wireless SHM sensor using frequency selective surface (FSS) as an alternative to conventional sensors. The electromagnetic wave characteristic of FSS will change by geometrical changes of FSS due to mechanical strain or structural failure. The changes feature is used as a sensing function without any connecting wires. Two type of design which are circular ring and square loop along with the transmission and reflection characteristics of SHM using FSS were discussed in this project. A simulation process has shown that incident angle characteristics can be use as a data for SHM application.

Antenna for a wireless sensor network for early wheel trains damage detection has successfully developed and fabricated with the aim to minimize the risk and increase the safety guaranty for train. Current antenna design is suffered in gain and big in size. For the sensor, current existing sensor only detect when the wheel malfunction. Thus, a compact microstrip patch antenna with operating frequency at 2.45GHz is design with high gain of 4.95dB will attach to the wireless sensor device. Simulation result shows that the antenna is working at frequency 2.45GHz and the return loss at -34.46dB are in a good agreement. The result also shows the good radiation pattern and almost ideal VSWR which is 1.04. The Arduino Nano, LM35DZ and ESP8266-07 Wi-Fi module is applied to the core system with capability to sense the temperature and send the data wirelessly to the cloud. An android application has been created to monitor the temperature reading based on the real time basis. The mainly focuses for the future improvement is by minimize the size of the antenna in order to make in more compact. In addition, upgrade an android application that can collect the raw data from cloud and make an alarm system to alert the loco pilot.

The development and transmission/reflection characteristics of a 3D dual cylinder Frequency Selective Surface (FSS) is presented. The investigation shows that the length of the resonant cylinders in the unit cell has significant effect on the frequency characteristics of the FSS, and the FSS can produce close band or highly selective responses. A stop and pass band very close to one another (essentially 1:1 band ratio) is achieved using equal length cylinders, without the need for any active components. Independently varying the unit cell cylinder heights produced a highly selective pass band with less than 0.3 dB insertion loss and deep nulls only approximately 500 kHz on either side. The dual cylinder 3D FSS was also experimentally verified, achieving very good agreement between the simulation and measurement results.

There are variety of lliquid sensor measurement systems that available in the market nowadays. It is used to measure various parameter for wide range application or to address a specific application. However, most of the existing monitoring system still involved bulky equipment and required a quite amount or liquid to be tested. The results obtained time consuming and take a long time to obtain the desired results. To solve the problems, we develop and design a small sensor using antenna that is small, robust as well as reliable and efficient to work as a sensor for liquid sensor detection. It is efficient and reliable to obtain in-situ result. The helical antenna is design using CST Software and the fabricated antenna is measured. The helical antenna works on 2 GHz frequency is tested with three different type of liquids and it is shows different liquid has their own frequency shift.

In this paper microstrip patch antenna for millimeter-wave is proposed. Evolution of shape microstrip antenna are designed which is from rectangular antenna to triangle antenna and changed to triangle with slot. The proposed antenna configuration achieved for covering 5G wireless system. The lowest return loss of the antenna is -29.23dB which is triangle with slot and the maximum gain obtained is 8 db at the 61.93 GHz for the triangle antenna. This antenna are suitable for the 5G wireless application for short range and high rate communication system.

One of the most used antennas in mobile devices is planar inverted F antenna (PIFA). PIFA can be design in dual band frequencies due to the coverage of the wireless service in a mobile device that requires a multiple frequencies. However, the consideration of technical operation has to be combined with an evaluation of the antenna radiation impact on the users. A procedure of PIFA work in GSM (867-960MHz) and GSM (1710-1899MHz) is done using CST Software. The dual band frequency response is obtained by means of an insertion of an L-shaped slot, which is use to tune the operation frequencies. The prototype of the antenna is fabricated as model by CST Software and evaluated. It is found out that the PIFA antenna has a good efficiency, bandwidth as well as produce a maximum gain for the antenna. A key and innovative research is still underway to broaden performance parameters of the antenna.

A novel 3D Frequency Selective Surface (FSS) with horn shaped resonators is proposed which exhibits a very wide stop band. This new horn shaped resonator is a modification from a 3D FSS consisting of square cylinder unit elements. This feature introduces frequency-selective surfaces with the added advantage of lowering the sensitivity of the FSS frequency response with respect to the incidence angle. Simulation results prove that the FSS can realize broad selectivity of waves with the bandwidth more than 57%. The wideband transmission behavior is stable under oblique TM incidence angles from 0 to 80 degrees. The influence of various key parameters on 3D Horn Shape FSS characteristics has been investigated using the CST simulation software tool. By understanding the effect of each parameter, a comprehensive study for a better design of 3D Horn Shape FSS with wideband response is presented.

The transmission and reflection characteristics of a dual cylinder 3D Frequency Selective Surface (FSS) is discussed in this paper. A simulation based investigation shows that the length of the cylinder has significant effect on the stop band frequency selective characteristics of the FSS. This can result in a closely spaced band pass and band stop response. A comparison is drawn to the introduction of dielectric materials into a single 3D cylindrical FSS.