Mohamad Huzaimy Jusoh

Circular patch antenna on metamaterial

This paper recommends a compact circular antenna on metamaterial substrate for C-band applications. The antenna has been designed to improve the performance of gain directivity, return loss and size. The size of the new metamaterial antenna has been reduced by a factor of 2.4 and the gain directivity was increased from 4.17 dBi in conventional design on Flame Retardant 4 (FR-4) to 5.66 dBi in the new approach. A better return loss was obtained from the metamaterial antenna which is −24.2 dB compared to −22.08 from the conventional antenna. By analyzing the radiation pattern, the metamaterial antenna has a sharp focus to the targeted direction. The compact antenna is expected to improve the cost of production due to the size reduction in a mess production.

Performance analysis for Estimation of signal Parameters via Rotational Invariance Technique (ESPRIT) in estimating Direction of Arrival for linear array antenna

Smart antenna refers to any type of antenna arrays combined with signal processor components which can adjust its own beam pattern in order to emphasize on the signal of interest and minimizing the interference signal. The accurate estimation of direction of interest which is also known as direction of arrival (DOA) of the incident signals is very significant to produce beam from antenna. There are several algorithms those have the ability in calculating the DOA of the incidents signals. In this paper an adaptive antenna is applied by using the most frequent used algorithm, estimation of signal parameters via rotational invariance technique (ESPRIT) to obtain the direction of arrival (DOA) of any incident signals. The exact number of samples and elements used is the most important parameter in the algorithms in order to sustain the accuracy of the direction of arrival of the incident signals. The optimization was done by running the program in cellular mobile environments. The data from the optimization was evaluated using SPSS in evaluating the performance of the algorithm.

Recognizing the ripeness of bananas using artificial neural network based on histogram approach

The main objective of this project is to develop a technique to classify the ripeness of bananas into 3 categories, which is unripe, ripe and overripe systematically based on their histogram RGB value components. This system involved the process of collecting samples with different level of ripeness, image processing and image classification by using artificial neural network. Collecting bananas sample is done by using Microsoft NX6000 webcam with 2 mega pixels. 32 samples were used as training samples for artificial neural network. In order to see whether the method mention above can classify the image correctly, another 28 images was used as a testing. From the result obtained, it was shown that the artificial neural network can generally classify the ripeness of bananas. This is because it can classify up to 25 samples correctly out of 28 samples. Developing a program totally by using Matlab version 7.0 can help classification process successfully.

Earthquake prediction technique based on GPS dual frequency system in equatorial region

The ionospheric Total Electron Content (TEC) measurements were investigated at Universiti Teknologi Malaysia, UTMJ on 20 February - 20 March 2007. The observation was made 14 days before earthquake and 14 days after earthquake. TEC is extracted using GPS dual frequency data which in RINEX format that supplied by JUPEM (Jabatan Ukur dan Pemetaaan Malaysia). In order to reveal possible earthquake precursor through the changes variation of TEC reading, Southern Sumatra Indonesia earthquake that happened on 6th March 2007 is chosen as a study case. The results show that satellite facilities may detect earthquake precursors in ionosphere 5-11 days or a few hours before main shock and various grounds based or satellite observation have shown strong perturbation of the ionosphere after earthquake. The results show a good agreement with other researchers who studied other earthquakes.

Implementation of Real-Time Kinematic Data to Determine the Ionospheric Total Electron Content

Ionosphere layer is an important medium in communication system. At this layer where the total electron content exist because of ionization by the Suns extreme ultraviolet radiation, meanwhile the night side ionosphere electron content is reduced by chemical recombination. Maximum Total Electron Content (TEC) was detected at 0500 Local Time Clock (LTC) and will decrease gradually and reached its minimum at 2200 LTC. TEC during the day is higher than at night. The ultraviolet (UV) radiation from the sun ionizes fractions of the neutral atmosphere and forms the ionosphere. The elevation angle of satellite will also influence the TEC value. The higher elevation angle, the value of vertical TEC will also increase. The data from GPS Stations in RINEX format is supplied by Department of Survey and Mapping Malaysia (JUPEM). The data is taken from two different stations located at GPS Station Arau, Perlis and GPS Station Universiti Teknologi Malaysia Skudai, Johor.

Design of hairpin band pass filters for K-Band application

This paper presents Chebyshev three and four poles microstrip hairpin filter for radar applications. The filters are operated at K-band frequency segment of 20-20.3 GHz. The filters were designed using Genesys software and implemented on Roger 5870 substrate. The results from simulation and measurement show that both filters were operating at the desired specification. Based on the experimental analysis, it was observed that the filter with four elements better than the three which was quite agree to other researchers.

Wi-Fi and GSM Based Motion Sensor for Home Security System Apllication

The Wi-Fi and GSM based home security system is a system designed to reduce the high rates of crimes in most personal housing. The overall project consists of three major parts; the input part that consists of sensors, the software part that operates the entire hardware structure, and the output part, which consists of camera, alarm system, and micro secure digital (SD) data storage card. It is based on the principle of infrared radiation generated by a human body heat which trigger the passive infrared (PIR) sensor. The microcontroller processes the received signal, then trigger the buzzer alarm, camera and alerts the home owner through an SMS. Once triggered, the camera will capture the image of the intruder and the image will be saved in SD card. As alert to the user (away), the Global System for Mobile Communication (GSM) will send the Short Message Service (SMS) from the device to the users mobile phone. The image will be sent to Dropbox data cloud storage via Wi-Fi for further clarification. The prototype was successfully developed, tested and has been installed at residential area in Taman Cahaya Alam, Section U12, Shah Alam, Malaysia.

Radio frequency radiation at satellite earth station for occupational safety and health

This paper presents on Radio Frequency (RF) Radiation at Satellite Earth Station and the effect to occupational workers and members of the public. This research and measurement was requested by OSH Committee, Satellite Earth Station, Telekom Malaysia Berhad as a result of concern raised by their workers and member of the public about potential health hazard caused by the RF radiation emitted by the Satellite Earth Station. This study shall produce the Radio Frequency radiation strength at Satellite Earth Station and the measurement will include the electric field strength, magnetic field strength and power density at certain identified locations at the Satellite Earth Station. In general, results of the research indicate that the radio frequency radiation present in the Satellite Earth Station were measurable but of very low levels. The result of the measured radiations is evaluated based on the exposure limits and the recommendations set by Malaysian Communications and Multimedia Commission (MCMC) and International Commissionon Non-Ionizing Radiation Protection (ICNIRP) for occupational workers and members of the public. Based on the evidences presented, the researcher is convinced that the health hazard is minimized and the radio frequency radiation at Satellite Earth Station has no adverse effect to the health, and the claim done by workers and member of the public at the Satellite Earth Station is unfounded and baseless.

Development of Low Power Anisotropic Magnetoresistive (AMR) Wireless Magnetometer for Earth’s Magnetic Field Measurement

Magnetometer is an instrument to measure Earth’s magnetic field magnitude. Microelectromechanical system (MEMS) magnetic sensor is implemented in the device system since it consists of multi-axis magnetic field sensing driven in a single microchip physical scale at low power consumption. The magnetometer is equipped with built-in data logger system as an automatic data storage system to overcome data loss. The Anisotropic Magnetoresistive (AMR) sensor is the best MEMS magnetometer sensors, since it consumes low power (3.3Vdc), small physical size (less than 8.1mm3) and considerable 200nT resolution for Earth’s magnetic field sensing. The magnetometer consumes 5.0Vdc for complete system operation. The instrument device is useful for scientific and geophysical field to observe and measure geomagnetic field magnitude, where the measurement could be taken anywhere around the globe. The mobile wireless magnetometer was tested and experimental measurement was performed at Faculty of Electrical Engineering, Universiti Teknologi MARA, Selangor, Malaysia (coordinate: 3.07°N, 101.50°E).

GPS Ionospheric Scintillation and Total Electron Content during partial solar eclipse in Malaysia

The most famous and known effects of space weather is fluctuation in the amplitude and phase radio signal that propagates in the ionosphere. This fluctuation is also known as scintillation which will intense, degrades the signal quality, reduce the information content, or cause failure of the signal reception. During solar eclipse day, there are some fluctuations to the signal received by GPS (Global Positioning System). The analysis of fluctuation can be used to predict the behavior of ionosphere during solar eclipse. The phenomenon in solar activity which is solar eclipse will occurs when the Moon passes between Earth and the Sun, thereby totally or partially obscuring the image of the Sun for the viewers on Earth. Scintillation at the ionosphere during the solar eclipse seems to be different compared to normal time. So, this research is mainly focuses on the effect of ionosphere corresponding to scintillation during solar eclipse. The method that will be used is analysing the GPS Ionospheric Scintillation and TEC Monitor (GISTM) data obtained from UKM Bangi station and Langkawi station using MATLAB. Before that, raw data that obtained from GISTM station will be converted into ASCII format using PARSEIM software. The result will be recorded in graph and tables to see the different of parameters value during solar eclipse happened and two days before and after it happened. The finding from this research is Total Electron Content (TEC) was decreasing when solar eclipse occurs as well as amplitude scintillation that also decreasing. Geographic storm and aurora were not one of the effect of solar eclipse.