Abstract:In this paper, electrical energy demand (load) of health centre at Ibeno beach in Akwa Ibom, was estimated based on watt-hour energy demand of the electrical appliances in the health centre. The estimated daily load demand is 35 kWh/day with peak load of 7.735 kW. The sea ambient temperature is about 8% lower than that obtainable on land while the wind speed on sea is about 67% higher than the wind speed on land. The cumulative effect of the lower offshore temperature and higher offshore wind speed is offshore PV cell temperature that is about 18% lower than the PV cell temperature on land. The system is designed with 3 days of autonomy and the resultant load demand will be satisfied by 11.41 kW PV modules and 4765.8Ah battery capacity which amounts to 64 units of the selected PV panels and 24 units of the selected battery.

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A detailed report of the spectrum occupancy measurement drive conducted outdoors in three rural villages of Asong in Mkpat Enin, Ikot Akpabio in Etinan, and Afaha Offioing in Nsit Ibom Local Government Areas of Akwa Ibom state in Nigeria on the UHF and VHF broadcast frequency bands is here presented. The spectrum usage on a highly conservative noise floor, was high in the VHF band, thereby not having enough free bandwidth for secondary spectrum access while the UHF band percentage utilization for the three villages were found to be at 33%, 41% and 55% with available free cumulative bandwidths of 264MHz, 232MHz, and 176MHz respectively. From the findings, Nigeria can comfortably accommodate a lightly licensed spectrum band in the UHF band to enhancer rural broadband services.

Indoor wireless systems poses one of the biggest design challenges although it is the most flexible and easily deployable method of implementing Local Area Networks. This difficulty in predicting the propagation of radio frequency wave in indoor environments is caused by reflection, refraction, diffraction and scattering of signals due to closed proximities to furniture, walls, human beings, and reflectors like ceiling, mirrors and glasses. To help improve the user experience and guarantee good quality of service in indoor situations, the research investigated the throughput and attenuation effect on signal with respect to 4, 5, 6 and 9 inches sizes of blocks walls respectively. The characterized Path-loss exponent was 1.999 and differed from the free space model, Wall and Floor Factor model and ITU model by 53.54dB, 6.42dB and 6.85dB respectively.

This paper presents statistical path loss models derived from experimental data collected in Port Harcourt in South-South region of Nigeria from 10 existing microcells operating at 876 MHz. The results of the measurements were used to develop path loss models for the urban (Category A) and the suburban (Category B) areas of Port Harcourt. The measurement results showed that the Pathloss increases by 35.5dB and 25.7dB per decade in the urban (Category A) and suburban (Category B) areas respectively. Variations in path loss between the measured and the predicted values from the Okumura-Hata model were calculated by finding the mean square errors (MSE) to be 10.7dB and 13.4dB for the urban and suburban terrains respectively. These variations (errors) were used to modify the Okumura-Hata models for the two terrain categories. Comparing the modified Hata model with the measured values for the two categories showed a better result. The developed statistical Pathloss models or the modified Hata models can be used in the urban and suburban areas of South-South Nigeria.