Wan Norsyafizan W. Muhamad

Microstrip Rectangular 4x1 Patch Array Antenna at 2.5GHz for WiMax Application

This paper presents the design of microstrip rectangular patch antenna with center frequency at 2.5GHz for WiMAX application. The array of four by one (4x1) patch array microstrip rectangular antenna with microstrip line feeding based on quarter wave impedance matching technique was designed and simulated using Computer Simulation Tool (CST) Microwave Environment software. The performance of the designed antenna was than compared with the single patch rectangle antenna in term of return loss, Voltage Standing Wave Ratio (VSWR), bandwidth, directivity, radiation pattern and gain. The array antenna was then fabricated on the substrate type FR-4 with dielectric constant of 4.9 and thickness of 1.6mm respectively. The array antenna was measured in the laboratory using Vector Network Analyzer (VNA) and the results show good agreement with the array antenna simulated performances.

Energy Efficient Lighting System Design for Building

Lighting contributes the highest amount of electricity usage in a building. Generally, lighting will consume from 20% until 50% of the electricity consumption. The efficient and effective use of lighting can offer major energy and cost saving. This research investigates and analyses the energy management in a building and presents the design of energy efficient lighting systems. The first part propose a design of energy efficient lighting which will help users to determine the ideal number of luminaries needed in certain room without reducing the quality of lighting. The design was develop via Matlab. The second part is an audit and cost study to demonstrate the wastefulness of commercial, industrial, residential and community lighting. Based on the study, the design for improvement of current lighting system called Lamp Replacement had been proposed. The major findings in this project are that the energy-efficient lighting design could still be achieved without sacrificing the visual comfort and quality of lighting and replacement of older fixtures with new luminaries can greatly improve efficiency.

Maximizing Network Lifetime with Energy Efficient Routing Protocol for Wireless Sensor Networks

In the research field of Wireless Sensor Networks, how to reduce the energy consumption of WSN so that the lifetime of WSN can be prolonged is one of the hottest spots. Wireless sensor networks (WSN) lifetime is either superficial or impractical, which prevents us from thoroughly understanding the efficiency of these proposed routing protocols. Routing protocols have significant impact on the overall energy consumption of sensor networks. This project present variety of maximizing system lifetime wireless sensor networks with different energy consumption. Energy consumption for three routing protocols had been analyzed which are direct communication, minimum transmission energy and low adaptive energy clustering hierarchy. The energy consumption for Low Energy Adaptive Clustering Hierarchy (LEACH) routing protocol give the maximum lifetime compared to the others. Clustering is an energy efficient and scalable way to organize the WSN. The main objective of this research is to maximize the lifetime of the wireless sensor (WSN). Simulation via Matlab shows that by applying energy consumption for LEACH routing protocol had increase the network lifetime by as much as 65.2% compared to DC and MTE.

Evaluation of Stable Cluster Head Election (SCHE) routing protocol for Wireless Sensor Networks

Wireless sensor networks (WSN) will enable the reliable monitoring of a variety environment for both civil and military applications. Routing protocols have significant impact on the overall energy dissipation of sensor networks. This project present the development of an energy efficient routing protocol which consumes significantly less power compared to existing routing protocol for wireless sensor network. The design was developed based on low energy adaptive clustering hierarchy (LEACH) routing protocol. Clustering is an energy efficient and scalable way to organize the WSN. The main objective is to minimize the energy dissipation of each sensor node and reduces the energy dissipation for the whole network. Stable cluster head election (SCHE) analyzes the cluster head selection to find the optimal probability of becoming a cluster head. Simulation of Matlab shows that this design reduces communication energy by as much as 95% compared to LEACH, due to stable cluster head election.

Single layer coconut shell-based microwave absorbers

This paper presents a study of single layer radar absorbing material made using coconut shell-based activated carbon. Flaxane-80 was used as binder and was mixed to give 10 wt%, 15 wt%, 20 wt% and 25 wt% variation of activated carbon obtained from coconut shell to study the microwave properties of the absorber material. An industry standard electromagnetic simulator was used to predict the absorber behaviour, while microwave non-destructive testing (MNDT) technique was used to measure microwave properties and reflection characteristics of the samples. The relative permittivity of 25 wt% carbon sample was found to be the highest with a value of 12. The sample also has the highest tan δ of 0.4. The thicknesses of absorbers made of 25 wt% carbon were varied at 3.2 mm, 6.4 mm, 9.6 mm and 13.8 mm to determine the reflection characteristics. The 6.4 mm sample was found to offer minimum reflection at 9.6 GHz with −22 dB reflection loss. Sample 9.6 mm has a minimum reflection loss of −17dB at 11.3 GHz. The results of this study offer great opportunities for RF application seeking for low cost and light-weight radar absorber material using coconut-shell.

Real Time Monitoring Critical Parameters in Tissue Culture Growth Room with SMS Alert System

Real-time monitoring critical parameter is enhanced with email and short messaging system (SMS) for alert system. This system consists of four subsystems which include data acquisition, website monitoring, email protocol and SMS system. The aim of the integrated system is to remotely monitor critical parameter in tissue culture growth room. Research has shown that factors such as temperature, humidity, liquid, phase and gas compositions are critical in producing quality clonal materials using tissue culture process. Consequently, sensors are required to monitor and record the data in growth room. All sensors will monitor critical parameters that will be linked to the database and analysis software for storing and analyzing the monitored data. For the purpose of remotely monitor critical parameter, website and SMS enquiry are developed. The system would monitor via telemetry system and provide automatically email or short message (SMS) notifications upon identification of a disturbance module.

Experimental verification of multi-layer coconut shell-derived microwave absorbers

This paper presents experimental results of our study on multi-layer microwave absorbers synthesized using coconut shells as the source of activated carbon. In this investigation, activated carbon with content variation of 0, 10, 15, 20, 25 and 30 wt% were mixed with Flaxane-80 to study the microwave properties of the absorbers. Three- and four-layer microwave absorbers with various carbon contents were fabricated to study their reflection properties. A microwave non-destructive testing (MNDT) set-up was used to evaluate the microwave properties. Samples with 30 wt% carbon composite showed the highest relative permittivity of 17. All the four-layer absorbers fabricated in this work showed excellent performance in absorbing microwave signals, exhibiting respectable wideband performance with bandwidths up to 38%.

Efficient network coverage for wireless sensor networks

Wireless sensor networks have a wide range of applications including environmental monitoring, habitat monitoring and disaster recovery. Since sensor nodes are deployed in a large land region, the objective is to achieve complete coverage of the region. It is crucial to develop a sufficient transmission signal between the node in the region or cell to the leader node or in base station. In previous research, network coverage is the main issue in WSN. This study presents an approach for the design of wireless sensor network under the deployment of hexagonal shaped cell with sectorized antenna. The proposed approach should be regarded as part of any feasibility study during the planning stages for the deployment of a wireless sensor network, when decisions about its efficient network coverage and cost are considered. The main objective of this project is to improve the communication coverage in the network. By improving the coverage problem, it will also reduce the number of sensor nodes deployed, hence reducing the cost.

Smart RFID system for oil palm bio-laboratory

The tissue culture laboratory provides the oil palm industry with innovations for the production of improved planting materials and information on the molecular biology of tissue culture processes. Research has shown that factors such as temperature, humidity, liquid, phase and gas compositions, are critical in producing quality clonal materials using tissue culture process. Therefore, it is necessary to provide good physical and chemical conditions for production of quality products. Consequently, sensors are required to monitor and record the data in growth room. All sensors will monitor critical parameters that focus on temperature, humidity, oxygen, carbon dioxide, ethylene and also an optical sensor for liquid phase and composition that will be linked to the database and analysis software for storing and analyzing the monitored data. The integrated sensors are low cost because it used local products and low power consumption and fabricated to suit the biological laboratory environment. The purpose of these integrated biotechnology sensors system is to serve as an interface among user, as the disturbance analysis program and an expert system in identifying the disturbance. The system would monitor via a smart RFID telemetry system and provide automatically email or short message (SMS) notifications upon identification of a disturbance module. Radio-frequency identification (RFID) is an automatic wireless identification method using radio waves, relying on storing and remotely retrieving data from integrated sensors using devices called RFID tags or transponders. Some tags can be read from several meters away and beyond the line of sight of the reader which make easier for data transportation. For the best communication path, active RFID tags will be equipped with autonomous networking; which greatly improves the utility of the device. Eventually, this smart RFID technology system could improve the efficiency of inventory tracking and management for oil palm tissue culture growth.

Chebyshev multi-layer microwave absorber design

This paper presents the use of Chebychev transformer in the design of multi-layer microwave absorbers constructed of coconut shells. The two, three and four multi-layer absorbers were modelled based on measured permittivity. The permittivity were obtained using microwave non-destructive testing (MNDT) from previous experiment. Then the permittivity of each layer was calculated using Chebychev multi-section transformer to provide a proper transition impedance. These microwave absorbers were modelled and simulated in MATLAB. The simulations were carried out from 1 GHz to 15 GHz to analyse the absorbers performance. The two-layer absorbers showed the multiple resonant frequencies. The permittivity of back layer influences the resonant frequency. A higher permittivity reduces the resonant frequency to a lower value. The two and three-layer absorbers showed an excellent bandwidth up to 110% and 120% respectively. The bandwidth can be improved by adding more layers to provide a smooth transition impedance between layers.