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A Modified COST-231-Hata Path Loss Model for Typical Semi-Urban Environments in Nigeria
(KIU Journal of Science, Engineering and Technology, 2024) AKANNI, Jimoh, ISA Abdurrhaman Ademola, OGUNBIYI Olalekan, OLUFEAGBA Benjamin Jimmy
Outdoor path loss propagation modeling is critical in the planning and design of the coverage area by the Global System for Mobile Communication (GSM). For the best prediction of GSM signal at any location within its coverage region, an accurate forecast based on critical characteristics and a mathematical model is necessary. Multiple studies on path loss propagation model prediction for GSM networks conducted at various semi-urban environments in Nigeria proclaimed that propagation path loss models may provide different results when utilized in environments other than those in which they were initially designed, that car drive-test methodology was used during the data collection, and that COST-231-Hata model provides closet prediction to the practical measure values. This paper created an appropriate path loss model based on the COST-23-Hata model and outdoor measurement at 1800 MHz frequency range for the semi-urban area of Kwara State, Nigeria. The created model was used and validated with the measured data and COST-231-Hata model at other different semi-urban environments in Nigeria. The results analysis shows that the created model performed satisfactorily given the closet path loss prediction to the practical measure path loss values at all the study locations. It also gives the lowest Square Root Means Error (SRME) and Standard Deviation (SD) in all the base stations that were tested in semi-urban environments. The newly created model would therefore be more appropriate for GSM 1800 network design and installation in semi-urban environments in Kwara State, Nigeria, as well as any other semi-urban locations in Nigeria.
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Performance Evaluation of a Laboratory-Scale Magnetic Field Pretreatment Device
(Nigerian Research Journal of Engineering and Environmental Sciences, 2023) Odewole, M. M., Ogunbiyi, O., Saka, A. A., Ayangbola, E.O. and Shehu, I. O.
Magnetic field as a method of food pretreatment is highly promising due to its non-thermal quality enhancement effects on foods. Magnetic field devices for conducting comprehensive food processing research works are not readily available, especially in developing countries. Also, an in-depth performance evaluation of the few developed magnetic field devices for food processing with a view to knowing the maximum magnetic field strength they can produce seemed not to have been done. Therefore, the objective of this paper was to present the performance evaluation of a laboratory-scale magnetic field device that can be potentially used for food pretreatment. The developed magnetic field device used works on the principle of electromagnetism and it can generate static, pulse and alternating types of magnetic field. It has a transformer designed to step down 240 V supply to 3.20 – 10.10 V for achieving different values of magnetic field strength; eight (8) electromagnets- each electromagnet has 0.3 m magnetic core perimeter and 200 turns of laminated copper wire (1.0 mm2, 60 m long and 1.2Ω). The performance evaluation of the device indicated approximately 30 mT as its maximum magnetic field strength. Therefore, the device is suitable for food pretreatment in future.
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Development and Implementation of a Prototype Automatic Rain-Sensor Car Wiper System
(J. Appl. Sci. Environ. Manage, 2022) AKANNI, J; OJO, AO; ABDULWAHAB, A; ISA, AA; OGUNBIYI, O
Various studies have been conducted over the years on how to reduce driver distractions while driving, but with little effort on the distraction that could be caused by manually operated wipers while driving whenever it rains. Drivers frequently take their hands off the steering to turn ON/OFF and adjust the wiper speed when driving during rain, which causes a loss of concentration and increases the risk of a car accident. This paper presents an automatic car wiper prototype system that adjusts the speed of the wiper based on the intensity of the rain. The system also includes an audio alert that warns the driver to stop driving during heavy rain. The rain sensor/intensity and servo motor; which regulates the wiper's speed, were interfaced by an ATMega328 (Arduino Uno A000066). It performed satisfactorily, with average response times of 0.78 seconds, 1.95 seconds, and 6 seconds for rain water detection, increasing rain intensity, and no rain detection respectively. The wiper speed was 15 rpm at moderate rain intensity and 32 rpm at heavy rain intensity. The wiper average response time and speed shows that it is a system that eliminate delay as compare to manually operated car wiper system. The developed system will reduce driver distractions while driving thereby reduces the risk of a car accident. As a result, this system can be combined with new technologies seen in contemporary vehicles.
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PROPAGATION LOSS DETERMINATION OF GSM SIGNAL STRENGTH IN SELECTED BUILDINGS IN ILORIN, NIGERIA
(ARID ZONE JOURNAL OF ENGINEERING, TECHNOLOGY & ENVIRONMENT, 2021) J. Akanni, O. T. Oraiye, A. A. Isa and O. Ogunbiyi
GSM signal building penetration loss is a problem often encountered by subscribers inside a building. As a result of building penetration loss, poor reception and signal outages often occur in many indoor locations and this accounts for increased attenuation of received signal strength of a cellular network signal when a subscriber with a mobile phone moves from outdoor to indoor. The study assessed the GSM signal penetration loss in thatched, wooden, block, mud and zinc buildings. Three network providers named A, B and C was used for the experiment. A low budget but very effective equipment (Two Tecno Pouvoir 3 plus Android phone) was used as the measurement tool. It was loaded with Network Signal Info application developed by KAIBITS Software GmbH installed software and positioned inside and outside the building to record indoor and outdoor GSM signal strength respectively for the three service providers in Ilorin, Nigeria. The results were then analyzed in order to determine and compare the path loss introduced by each of the selected buildings. This process was repeated for all the selected buildings, and the measurement was carried out for 6 months. The findings revealed that the outdoor signal strength was higher than the indoor signal strength for all the selected buildings; it also revealed that penetration loss is likely to be a function of the material used in the construction of the buildings. Zinc building has the highest penetration loss of 12.0dBm and thatched building has the least penetration loss of 2.6dBm. Information from this research will assist in selection of building materials for good indoor cellular network signal reception. It will also assist cellular network service providers in the link budget preparation for environments where similar building materials are used.
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LOSS MITIGATION ON SULEJA 33KV NETWORK USING STATCOM DEVICE
(Academic Journal of Current Research, 2022) J.K. Ogunjuyigbe, O. Ogunbiyi, L.M. Adesina, and S.A. Benson
The load flow analysis was carried out to establish base voltage at various buses. The buses that have the voltages fall below the prescribed or nominal voltage range between 0.95 and 1.05 p.u. volt are considered as faulty buses. These include bus 1, bus 4 and bus 5 with per unit volts of 1.06, 1.057 and 0.8897p.u respectively. After the incorporation of STATCOM, the p.u. volts at buses 1, 4 and 5 improved to 1.025 p.u., 1.026 p.u. and 1.01 p.u. respectively. The total active power loss without STATCOM is 323.9891MW while that of the reactive power loss 50.07631MVar and the total active power loss with STATCOM is 275.6053MW while that of the reactive power loss is 18.79948MVar. The losses were reduced when STATCOM was incorporated into the distribution network. Therefore, the percentage of power system improvement is 17.6% when STATCOM was incorporated