Khalid A. Saeed Al-Khateeb

Intelligent dynamic traffic light sequence using RFID

The proposed RFID traffic control avoids problems that usually arise with standard traffic control systems, especially those related to image processing and beam interruption techniques. This RFID technique deals with a multi-vehicle, multilane, multi road junction area. It provides an efficient time management scheme, in which a dynamic time schedule is worked out in real time for the passage of each traffic column. The real time operation of the system emulates the judgment of a traffic policeman on duty. The number of vehicles in each column and the routing are proprieties, upon which the calculations and the judgments are based.

A proposed vertical path adjustment factor for dust storm attenuation prediction

In this paper an adjustment factor which reflects the vertical variation of dust storm (earth satellite links) has been derived based on the analysis of the vertical dust storm behavior. The paper has been divided to four parts. First an introduction to the dust storm phenomena and its effect on microwave signal attenuation. Secondly, observations of the behavior of the vertical dust storm intensity variation. Thirdly, the vertical path adjustment factor has been estimated. Lastly, a conclusion summarized the results and recommended further work. It has been found that the predicted attenuation without the vertical path adjustment factor is much higher than with the vertical path adjustment factor. Therefore, the vertical path adjustment factor will provide optimum utilization for the transmission resources.

Availability Analysis of Terrestrial Free Space Optical Link under the Impact of Rain Condition

Availability is one of the main factors to measure the QoS of any telecommunication networks. An accurate availability prediction for Free Space Optical link of carrier class grade is needed. In tropical areas, rain is the most dominant factor affecting the FSO link availability. In this paper, the effect of rain attenuation on the availability of FSO links is analyzed by examining the impact distance of different FSO systems. As the rain attenuation of FSO is independent of wavelength, the analysis of rain attenuation will be based on rain intensity. ITU-R (Carbonneau and Japan) models have been used for the analysis. From the results, Carrier class availability with good enough resolution for estimated availability can be predicted. This paper provides recommendations to FSO researchers in general and local telecom service provider in particular about possible availability figures that can be useful for deployment of FSO link as a last mile solution, back-up for fiber optic and other applications.

A low-cost first-order sigma-delta converter design and analysis

This paper presents the design and analysis of an interface circuit for MEMS or biomedical sensor applications. This circuitry performs the function of an analog-to-digital converter. A first-order 1-bit sigma-delta (Σ-Δ) analog-to-digital converter is designed and simulated using Silterra 0.13μm CMOS process technology with power supply of 1.2V through Cadence. Then the circuit simulation results are transferred to MATLAB, in order to get the frequency domain power spectral density (PSD). The simulation results on noise and error analysis are compared with those from a traditional analog-to-digital converter to prove that sigma-delta is performing better in the case of weak signals acquisition.

An Emergency Medical Care Network System for Fetal ECG Monitoring

Developing and less developing countries (LDCs) are identified in risk of stillbirth due to insufficient emergency medical take-care supports. The regular check-up of the fetal electrocardiography (FECG) could be an earliest prevention of this occurrence. This paper presents a research work aim to implement a simple, customize and portable emergency medical care for the FECG monitoring system from remote location. After acquisitions of the abdominal wall fetal electrocardiography (AFECG) signal from the pregnant mother (patient), the local terminal then transfers this AFECG signal as data to the remote terminal at the expert physician for diagnosis purpose. At the remote terminal, the FECG signals are then extracted from the AFECG signals by our developed software. In this case, computer network establishes a bridge between the patient and a distant expert physician. The network program developed based on the client/server applications. The developed network program is capable to support both the AFECG data transfer and online chat session simultaneously. A specialist physician at the remote terminal can diagnose the FECG signal and provides instruction to the local terminal in case of emergency. A number of cases studied by this developed system and found approximately same result compared with a commercial system.

Preliminary analysis of Ku-band rain fade data for earth-to-satellite path measured in Malaysia

The dynamic characteristics of rain fade slope are one of the important factors in the determination of the earth-to-space communication system availability. It is also useful in the design of the fade countermeasures. This paper investigates the rain fade slope which is one of the main features of fade dynamics with 0.1s, 0.5s, 1s, 2s, 5s and 10s sampling time intervals. The rain fade slope model proposed by the ITU-R was compared with the corresponding statistics obtained from rain attenuation data measured using MEASAT3 downlink at Ku-band in Malaysia during May 2010 - June 2011. Significant discrepancies have been observed between the measured fade slope data and that predicted by the ITU-R prediction model with different sampling time interval.

Implementation of Internet based remote control and monitoring

Remote monitoring and control of a multiunit industrial facility can be achieved by utilizing the Internet. Electrical, mechanical and a variety of devices are switched on, off, and regulated from distant terminals. Commercially available components were used to build the system. Various aspects related to the method of access, security, standards, and current trends are discussed. An eight unit system has been implemented and tested. The system proved to be effective and easy to operate with a user friendly program, which can be readily adapted to deal with 256 units simultaneously. The wiring is reduced by using the ordinary power lines of the building to convey messages to and from the respective units. The system is also suitable for implementation by security and SCADA systems.

Comparison of the effect structure on Ring and Linear Cavity Lasers of Er-Doped Optical Fibers

Two erbium doped fiber laser configurations are conceived and constructed; A ring fiber laser and a linear cavity fiber loop laser. A comparative investigation tests were carried out. It is found that both the output power and the side mode suppression ratio (SMSR) for the two structures were significantly different. The measured laser power and the side mode suppression ratio (SMSR) of 11 mW and 75 dB respectively were higher for the linear cavity configuration. A lower output power and SMSR of 3 mW and 61.5 dB respectively were obtained with the ring laser configuration. Both lasers were pumped with a 90 mW pump power, and had a reflectivity of 90%.

A Novel Erbium-Doped Fiber Laser source (EDFL)

A novel configuration of a new erbium doped fiber laser (EDFL) is constructed and analyzed. It utilizes embedded fiber-loop mirrors, tunable filters with a linear laser oscillation. Implementing the linear cavity fiber loop (LCFL) as a new configuration using three circulators and two tunable band-pass filters (TBF), the output power in the single wavelength (SW) laser was improved. The output power of the proposed laser system is more than 18 dBm at 1560 nm. The side mode suppression ratio (SMSR) in the output power in this experiment was also high, greater than 64 dB. It is found that the double filtering technique in the proposed configuration enables the system to achieve higher power and lower amplified spontaneous emission (ASE) noise levels.

Analysis of rain fade duration over satellite-earth path at Ku-Band in tropics

Statistical analysis is fundamental information for system engineer to design and plan satellite communication link. Fade duration is one aspect of fade dynamics that contributes designing of fade mitigation techniques (FMT). This paper presents statistical analysis on fade duration on high elevation angle (77.4°) in Ku-band carried out in Kuala Lumpur, Malaysia with 12 months duration statistics.