Ade Syaheda Wani Marzuki

Performances analysis of VoIP over 802.11b and 802.11e using different CODECs

This project is to simulate the Voice over Internet Protocol (VoIP) over IEEE 802.11b and 802.11e WLANs (Wireless Local Area Network) with different Coder-Decoder (CODECs) by using Network Simulator-2 (NS-2). The main objectives of this project are to analyze the VoIP of Mean Opinion Score (MOS), throughput and packet drop rate. The simulation is conducted using different CODECs (G.711, G.729A and G.723.1) and simulated without background traffic (data). The simulation in this project is using 1 wired node and 1 access point connected with mobile nodes in hierarchy. The mobile nodes will send VoIP calls to wired node through access point simultaneously. From the project, it is found that the CODEC G.711 provides the best quality of VoIP calls. However, CODEC G.723.1 can support the most VoIP calls with acceptable quality. In addition, with the first priority given by 802.11e to the VoIP, it can provide a very good perceived audio quality.

Biological Effect of 900MHz and 1800MHz Mobile Phones in SAR Weight

In recent years, the public concern on human biological effect of mobile phone is increasing due to the widely used of mobile phones by public including the children. As a consequences, a safety guidelines have been established by the various public organization such as World Health Organization (WHO) and International Commission on Non-Ionization Radiation Protection (ICNIRP). The main objective of this paper is to investigate and study on the human biological effect that may cause by the used of 900MHz and 1800MHz mobile phones. For the purpose of the assessment, Finite-Difference Time Domain (FDTD) is used to simulate the modeling of mobile phone attached to human head in order to obtain the Specific Absorption Rate (SAR) value of mobile phones that absorbed into human head. The minimum SAR value stated by International Commission on Non-Ionization Radiation Protection (ICNIRP) is 2W/kg. When the limit is exceeds, it may produces adverse human health effects that contibute to reverse cell membrane polarity, alter brain waves and damage DNA. This leads to cancer and memory loss. However, mobile phones are designed with low power and operate at high frequency, resulted in lower SAR value comparing to 2W/kg that stated by ICNIRP. Other temporary biological or potential human health effects that may produce by mobile phones are heating, headache, fuzziness, fatigue and nausea. By the way, further studies or researches are needed in order to draw more complete picture of health risks that may cause by the used of mobile phones.

Human health implication of 900MHz and 1800MHz mobile phones

In recent years, there has been increasing public concern about the health implication of Electromagnetic (EM) wave exposures due to the mobile phone. For this reason, various public organizations in the world have been established safety guidelines. This paper focused on the investigation or study of human health effect that cause by the used of 900MHz and 1800MHz mobile phones. For the purpose of the assessment, Finite-Difference Time Domain (FDTD) is used to find the Specific Absorption Rate (SAR) value of mobile phones that absorbed into human head. The minimum SAR value stated by International Commission on Non-Ionization Radiation Protection (ICNIRP) is 4W/kg. When the limit is exceeds, it produces human health effects where it can caused reverse cell membrane polarity, alter brain waves and brain chemistry and damage DNA. This leads to cancer and memory loss. However, mobile phones are designed with low power and operate at high frequency where the value of SAR is lower than the limit that stated by ICNIRP. Other temporary biological or potential human health effects produce by mobile phones are heating, headache, fuzziness, fatigue and nausea. By the way, further studies or researches are needed in order to draw more complete picture of health risks that cause by the use of mobile phones.

Visualization and Analytical Measurement of Electromagnetic Radiation from Handheld Mobile Phones

Mobile communication is where signal is transferred via electromagnetic wave through radio frequency and microwave signals. This signal produced electromagnetic radiation in the form of thermal radiation that consists of harmful ionizing radiation and harmless non-ionizing radiation. When using mobile phone, electromagnetic wave is transferred to the body in the form of thermal radiation that might cause health problems especially at the place near ear skull region for a certain period of time (talking time or operation time). In this analysis, the simulation and experimental analysis are carried out to examine the effect of electromagnetic radiation towards design phantom (dry phantom), water molecules and human volunteer when using the mobile phone for 45 minutes talking hour. This analysis is conducted in an anechoic chamber. Simulation is done using MATLAB’s software to show the radiation produced by the mobile phone. In the experimental analysis, thermal imaging technique is used to monitor and capture temperature distribution towards design phantom and human head. Two different design of mobile phone are used with internal (built-in) and external monopole antenna serving two different GSM frequencies GSM 900 and GSM 1800. The results show that mobile phones produced electromagnetic radiation (thermal) towards human head with high radiation produced by mobile phone with external antenna serving for GSM 900 MHz.

Development of shape pattern recognition for FPGA-based object tracking system

This project presents Field Programmable Gate Array (FPGA) based solution for an object tracking system. The tracking design was applied in FPGA as rich information of FPGA offers one of the more powerful methods in object tracking. Object tracking system has a very useful application in many real world situations which require object detection. In general, a lot of different algorithms are used in various types of object tracking system such as the detection of handwriting, moving objects, barcodes etc. This project is focusing on shape detection to observe the real object image. This paper starts by describing the method of converting RGB image to binary signal using MATLAB. Then the binary signal is used as an input signal for the detection part. Detection algorithm used in the design is using a fixed method. The simulated waveform shows that the algorithm design can detect the shape correctly if and only if the input image is clear, located in the center of the image and does not flip or rotated. Verification done using FPGA board also proven that. But there are lot of improvement can be done to improve the design such as increasing the size of the binary signal for the input of the system.

900MHz and 1800MHz mobile phone effect towards adult head in SAR distribution and SAR in weight

The investigation on the effect of mobile phone towards adult head in Specific Absorption Rate (SAR) Distribution and SAR in Weight is presented in this paper. Finite Different Time-Domain (FDTD) was used to construct adult head modeling with the attachment of monopole antenna and also to do a simulation in obtaining the SAR Distribution and SAR in Weight either 1g or 10g weight value, respectively. From the simulation, the results show that the values of both SAR are small and do not exceed 4W/kg stated by International Commission on Non-Ionizing Radiation Protection (ICNIRP), National Council on Radiation Protection and Measurement (NCRP) and Institute of Electrical and Electronics Engineers (IEEE). The simulation covered 900MHz and 1800MHz frequency with 0.6W radiated power.

A Thresholding Algorithm for Text/Background Segmentation in Degraded Handwritten Jawi Documents

The old documents in Jawi script are being used widely for references. The hard copies of those scripts will deteriorate as time passes. Most of the previous works on Jawi documents focused on the character recognition and the accuracy of the algorithm was very much affected by noise. An effective preprocessing method is required to binarize degraded Jawi document. In this paper, a new technique to threshold degraded Jawi document is proposed. The results of the new algorithm were also evaluated and compared with several algorithms. The quality of the thresholding methods was assessed using visual inspection and mathematical evaluation. The results show that the new technique has outclassed other binarization algorithms.

Pseudo random binary sequence on second order system

Pseudo random binary sequence (PRBS) signal was developed using MATLAB software and used as a forcing function in simulated second order system. The autocorrelation function (ACF) of the input signal and cross correlation function (CCF) between input and output signal were performed using MATLAB software and transfer function of the system was estimated from the correlograms. For verification of the simulation work, PRBS generator circuit was build using transistor-transistor logic and analyzed using Dynamic Signal Analyzer (DSA). PRBS is used as forcing function to an unknown system. The ACF of the input signal and CCF between input and output signal were performed using DSA and the transfer function model of the unknown system was estimated.