Browsing by Author "Bello, Olayiwola W."

Now showing 1 - 3 of 3
  • Item
    HATA, COST - 231, EGLI and ILORIN - A Performance Assessment
    (Faculty of Engineering and Technology, Ladoke Akintola University of Technology, Ogbomosho., 2014) Ayeni, Adeseko A.; Faruk, Nasir; Sowande, Olugbenga A.; Onidare, Samuel O.; Bello, Olayiwola W.; Surajudeen-Bakinde, Nazmat T.
    Information carried through the wireless medium are subject to impairments due to several events along the route of transmission, leading to path losses. For effective network planning therefore, these events and their effects on radio propagation need to be known and accounted for. In this work, we studied the radio propagation profile, along selected routes in Ilorin, Kwara State due to transmissions from the NTA, Ilorin, the Harmony FM and the University of Ilorin FM transmitters. Each of the routes are divided into segments, as seen, in the figures. The measurements were made, using the N9432C Agilent spectrum analyzer. Analysis, of obtained data, showed that the nature of the environment, affects radio propagation. Even within the same route and all other conditions the same, the models’ relative performances vary, from one segment to the other. The performances of the models corroborate the notion that empirical models are environment-specific.
  • Item
    Large Spectrum Survey in Rural and Urban Environments, within the 50 MHz - 6 GHz Bands
    (ELSEVIER, 2016) Faruk, Nasir; Bello, Olayiwola W.; Sowande, Olugbenga A.; Onidare, Samuel O.; Muhammad, Mujaheed Y.; Ayeni, Adeseko A.
    In-depth spectrum measurement was conducted in rural and urban locations, covering 50 MHz - 6 GHz bands, during the weekdays and weekends. A modified duty cycle metric is presented by introducing a space variable into the existing metrics available today. An adaptive energy detection threshold technique was employed, the results indicate the average spectral occupancy of 0.18%, and 5.08% in rural and urban locations respectively during weekdays and 1.45% on weekends for urban locations. Furthermore, short and long term temporal variations of the duty cycle for each of the bands were studied, and it was found that GSM 900 shows significant temporal variation when compared with GSM 1800. It was also found that the choice of the detection threshold would significantly affect the duty cycle as GSM 900 and 1800 give exponential decay with increase in detection threshold while TV band shows very sharp exponential decay which becomes invariant after -85 dBm
  • Item
    Practical Error Bounds of Empirical Models at VHF/UHF Bands
    (2016) Onidare, Samuel O.; Faruk, Nasir; Bello, Olayiwola W.; Mohammed, Mujaheed Y.; Sowande, Olugbenga A.; Ayeni, Adeseko A.
    Empirical path loss models are widely used to predict signal propagation behavior in an environment. In this paper, a multi-transmitter scenario was used to bound the errors of five widely used empirical propagation path loss models in predicting radio waves propagation in the UHF and VHF bands in Ilorin metropolis, Nigeria. A drive test was conducted using a dedicated Agilent N9342C spectrum analyzer along seven different routes that span urban and open areas. Three transmitters were utilized in the campaign (National Television Authority NTA Ilorin, Harmony FM and Unilorin FM). The prediction error, root mean square error (RMSE), skewness of the error distribution and the relative error were further computed and presented. Furthermore, the performance of the models were also cor-related with their design parameters and constraints. The analysis reveals that, of the five models investigated, the error bounds of the ECC model is very high, hence its accuracy for Ilorin terrain, while the three models of Cost-231, Hata and Ilorin (a localized model) were below the acceptable tolerable values for the metrics used and the Egli model falls within a reasonable range of the acceptable values of 6-7dB for urban areas and 10-15dB for Suburban and rural areas. For example, while the ECC model recorded RMSE values of 54.11dB, 52.23dB and 52.41dB for the three transmitters, the corresponding values for the Hata model were; 7.9 dB, 8.37 dB and 10.13 dB, for the COST 231 model: 8.46 dB, 10.09 dB and 9.66 dB and for the Ilorin model, the RMSE values were; 8.51 dB, 8.50 dB and 10.57 dB. The RMSE values obtained for the Egli model are 16.77 dB, 14.50 dB and 10.90 dB respectively. Finally, it was found that the error distribution for each model followed the terrain profile of the routes.