Fairul Afzal Ahmad Fuad

Energy consumption optimization with Ichi Taguchi method for Wireless Sensor Networks

Wireless Sensor Networks (WSN) consists of sensor nodes for monitoring and reporting sensible changes on a field to a specific server. One of the applications of WSN is large area monitoring, where sensor nodes are placed in far fields with limited power sources. Due to the adhered reason, the energy consumption of sensor nodes is considered as one of the major challenge in WSN. Many factor in WSN contributes to energy consumption such as Medium Access Control protocol (MAC), the network topology, and routing protocol. With the variety of factors that affects the energy consumption in WSN; the challenge of optimizing WSN networks toward a low energy consumption is becoming a hard problem. In the literature many efforts are paid for designing, implementing, and improving protocols in terms of power consumption. However, few efforts are paid for optimizing the existing protocols and other network parameters toward a green technology. This paper focuses in WSN infrastructure and protocols optimization by introducing the Ichi Taguchi (Taguchi) optimization method. Taguchi method is used to predict the best design parameters to achieve optimal performance parameters. Moreover, Taguchi method is used to optimize the energy consumed by sensor nodes against network protocols and network topology design parameters. A simulation experiments are curried out on the discrete event simulator OMNET++ for the purposes of this research paper. The obtained results show the impact of the network protocols toward the energy consumption. Furthermore, a proposed network topology and protocols set is introduced, and compared against the existing once.

Hardware Implementation of Modeling Frequency Coded Serial Communication for Eurobalise Using ASK Module

This paper discusses about the modeling of frequency coded serial communication for the application of Eurobalise on hardware-based field programmable gate array (FPGA). The transceiver consists of FPGA and the ultra-high frequency (UHF) band amplitude shift keying (ASK) module. In the convention interface of the ASK transceiver module with the digital controller, noise has introduce into the channel. The noise in the output of ASK receiver has distorted the transmitted data causing the throughput of the wireless channel to be decreased. When the ASK module interfaces with the FPGA device, the noise from the output of the ASK receiver causing the receiving FPGA retarded. The purpose of the frequency coded serial data is to provide continuous specific frequency pulse train to the ASK transmitter. The original serial bit stream is then modulated in the pulse train with different frequency corresponding to the bit’s logic level. This technique has made the output of the ASK receiver to produce a very clean signal with extremely less noise. Hence, the receiver’s FPGA able to capture all the transmitted data accurately across traditional disciplinary boundaries, including computer hardware, algorithms, electronics interfacing and application domain.

Short-Term Non-ionizing 2.45 GHz WBAN RF Exposure Does not Affect Human Physiological Measures and Cognitive Performance Exposed by Wearable Textile Monopole Antenna

This paper presents a novel study of evaluating non-ionizing effect of 2.45 GHz Wireless Body Area Networks (WBAN) radiofrequency (RF) electromagnetic fields (EMF) exposure on human physiological parameters and cognitive performance. The study aims to test the hypothesis whether exposure of 2.45 GHz WBAN radio electromagnetic fields may affect physiological parameters and cognitive performance of human. Twenty healthy volunteers are involved in the test and exposed to 2.45 GHz WBAN RF radiation, emitted by a planar textile monopole antenna. Physiological measures of body temperature, systolic blood pressure, diastolic blood pressure and heart rate are obtained, along with cognitive performance outcomes. Results indicated that no significant difference is observed in any of the three sessions (pre, exposure and post) for all physiological parameters, p > 0.05. Insufficient evident is found to indicate a difference in mean of all cognitive tests between WBAN RF and Sham exposure sessions, p’s > 0.05.

Wettability Study Using O2 and Ar RIE Gas Treatment on Aluminium Surface

Wettability is one of the most important aspects in microfluid technology. The effect of surface roughness on the wettability by a liquid has been studied experimentally using Design of Experiment(DOE). Sixteen samples were etched using Reactive Ion Etching (RIE) technique with different combination of parameters. RIE parameters concerned in this experiment are ratio of Oxygen, Argon, ICP power and BIAS power. Reactive Ion Etching influences surface morphology which is correlated with the contact angle produced. This preliminary study is to gain information on the how does RIE affects the aluminum bondpad in terms of surface roughness and contact angle.

Grain Size Analysis on Ba0.65Sr0.35TiO3 Thin Films Using Design of Experiment

This paper presents the relationship between spin coating speed, heat treatment time, and annealing temperature in response to the grain size in ferroelectric Barium Strontium Titanate (BST). Many fundamental issues such as heat conduction, contact deformation, mechanical stress, and friction can be explained and distinguished through the understanding of the grain size. The investigation was done using a full factorial design of experiment (DOE). Analysis was done quantitatively by plotting the main effects graphs. The results suggest that higher spin coating speed and the annealing temperature decreases the grain size while the heat treatment time is directly proportional to the value of grain size.

Quantitative Bump Height Analysis in ENIG Using Design of Experiment

Flip chip technology has grown by leaps and bounds and is getting even smaller in size. Optimization of process parameters in manufacturing is eminent due to reliability issues. This paper reports the parameters that affect the quality of the bump height in electroless nickel immersion gold (ENIG) and their relationships between each other. A total of four different combinations of parameters have been carried out for this investigation using the design of experiment (DOE) approach. It can be concluded that higher temperature of electroless nickel permits an increase of bump height where as the increment in immersion gold temperature does not nessasarily affect the value of bump height. All four samples recorded a higher value of bump height than the controlled bump height value. This implies reliability of the solder joint and assembly process robustness can be improved with an increase of bump height by increasing the time.

Relationship between Controllable Process Parameters on Bump Height in ENIG

This paper reports the factors that affect the bump height in electroless nickel immersion gold (ENIG) and their interrelation between each other. Bump height is a critical issue that needs to be investigated because a certain quality and requirements of bump height needs to be achieved prior to reflow oven soldering process. A total of four controllable process variables, with 16 sets of experiments were studied using a systematically designed design of experiment (DOE). The result suggests that the electroless nickel bath time has the most significant effect on the formation on bump height and consequently provide larger area for conductivity.

Bump height at low temperature analysis

The effects of chemical bath time in response to the bump height in electroless nickel immersion gold (ENIG) process was investigated. This paper presents the correlation between electroless process time, immersion gold process time and the bump height. A certain bump height need to be achieved in order to create acceptable solder bumps for reflow process. The study was done using a full factorial design of experiment (DOE). The DOE matrix is made of two levels with two factors. Analysis was done by plotting the main effects plot for each factor. The results suggest that higher process time increases the plating rate where the temperature fixed at 70 °C. Electroless nickel time has more influence to the bump height compared to immersion gold time.

Aluminium Surface Grain Size Analysis on RIE Treatment

Reactive Ion Etch (RIE) has been an important process in the world of microelectronic fabrication. Focus of this preliminary study is on how RIE affects the grain size of aluminum film which is fabricated on substrates. RIE parameters are varied to obtain 16 different recipes which are done using Design of Experiment. Grain size of the samples is recorded for all 16 samples before and after RIE treatment. This produces results that can be compared to obtain the effect of RIE on the aluminum film. Results show that RIE affects the mean grain size of the aluminum film as it increases after RIE treatment.

5mm × 5mm Sized Slug on High Power LED Stress and Junction Temperature Analysis

Conventional incandescent lamps are being replaced by high power light emitting diode as a lighting source due to it ascendancy in terms of physical size, performance, output and lifetime. Nevertheless, the reliability and efficiency of the LED is dependent on the junction temperature. This study presents the thermal simulation of single chip LED package with 5mm x5mmx 1mm aluminum heat slug. The junction temperature and stress of LED chip were evaluated using Ansys version 11. Input power of 0.1 W and 1 W were applied to the LED. The simulation results showed that at input power of 1W, the maximum junction temperature and stress of the LED chip is 112.91°C and 263.82Mpa respectively.