المؤلفون: Akinbolati, Akinsanmi, Ikechiamaka, Florence N., Isaiah, Akogwu O.

المصدر: Journal of Electronic & Information Systems; Vol. 5 , Iss. 1 (November 2023); 45-50 ; 2661-3204

مصطلحات موضوعية: Effective earth radius factor (k-factor), Refractive effect, errestrial radio link, Radio signal, Power budget

الوصف: The effective earth radius factor (k-factor) has a refractive propagation effect on transmitted radio signals thus making its study necessary for the proper planning of terrestrial radio links and power budget. This study was carried out over the city of Lokoja, Nigeria, using ten years (2011 to 2020) atmospheric data of temperature, pressure and humidity both at the surface (12 m) and at 100 m AGL. The data were retrieved from European Centre for Medium-Range Weather Forecasts (ECMWF) ERA5. The k-factor yearly variation follows the same trend with minimum and maximum values obtained during dry and wet season months respectively. In addition, the highest mean value of 1.00042 was recorded in the month of August while the lowest value of 1.00040 was recorded in the month of January with an overall mean value of 1.0003. This value is less than the recommended standard of 1.33 by ITU-R. The propagation effect corresponding to k < 1.33 is sub-refractive. The implication of this on radio wave propagation, especially terrestrial communications is that transmitted wireless signal is prone to losses. This can be mitigated through an effective power budget: Choice of transmitting antenna’s height and gain, so as to improve the Quality of Service over the study area.

وصف الملف: application/pdf

العلاقة: https://journals.bilpubgroup.com/index.php/jeis/article/view/5583/4830Test; https://journals.bilpubgroup.com/index.php/jeis/article/view/5583Test

الإتاحة: https://journals.bilpubgroup.com/index.php/jeis/article/view/5583Test

المؤلفون: Sabiru, Aminu Yaradua¹ (AUTHOR) aminu.sabiru@umyu.edu.ng, Akinbolati, Akinsanmi^1,2 (AUTHOR) aakinbolati@fudutsinma.edu.ng, Ikechiamaka, Florence N.² (AUTHOR) fosuagwu@fudutsinma.edu.ng, Abe, Bolanle T.³ (AUTHOR) abebt@tut.ac.za

المصدر: Advances in Space Research. Jul2024, Vol. 74 Issue 2, p890-898. 9p.

مصطلحات موضوعية: *RADIO wave propagation, *CITIES & towns, *WIRELESS communications, *RADIO (Medium)

مصطلحات جغرافية: KADUNA (Nigeria), SOKOTO (Nigeria), KATSINA (Nigeria)

مستخلص: A good understanding of the behavior of the atmosphere is a key factor in radio wave propagation and link's design. This study investigated the influence of refractivity gradient, effective earth radius factor (k-factor) and geo-climatic factor (K-factor) on radio communication over the cities of Kaduna, Katsina and Sokoto, in Northwestern parts of Nigeria. Forty-one year's secondary data (1980–2020) of temperature, pressure and humidity at the surface 12, 100 and 250 m above ground level retrieved from European Centre for Medium-Range Weather Forecasts (ECMRWF) ERA-5 reanalysis were used for the study. The three secondary radio-climatic parameters under investigation were computed and analyzed using latest ITU-R (Rec.P.453-14 (08/2019)) Models. It was observed that secondary radio-climatic variables exhibit seasonal type dependence. The research also reveals that the secondary radio-climatic variables depend on location, with all the study locations having different values. The highest value of refractivity gradient obtained is about −75.06 (N-units / km) in the month of February in Sokoto while the least of about −162.65 (N-units/km) was recorded in Kaduna in September. The value of the refractivity gradient is higher during the dry season compared to the wet season months with Sokoto recording the highest values for more than half of the months, followed by Katsina. Kaduna recorded highest number of lowest values of refractivity gradient. For the geoclimatic factor, it was revealed that Kaduna has an average maximum geoclimatic factor of 14.0000E-5 in September and an average minimum of 9.6677E-05 in February. Furthermore, the obtained values of k factor values for the study areas are higher than the standard value of, 4 3 (1.33). The k-factor in Kaduna ranges from 1.69 to 2.16 with mean value of 1.85 for dry season while for the wet season it ranges from 2.66 to 4.12 with a mean value of 3.74; the overall mean value for Kaduna is 2.80. In Katsina, it ranges from 1.66 to 2.20 with mean value of 1.81 for dry season while for the wet season it ranges from 1.95 to 4.00 with a mean value of 3.27; the overall mean value is 2.54. In Sokoto it ranges from 1.60 to 2.30 with mean value of 1.78 for dry season while for the wet season it ranges from 1.72 to 3.45 with a mean value of 2.59; the overall mean value is 2.19. The interpretation of this is that, radio signal propagation in the Northwest region of Nigeria is super-refractive. The overall findings of this research are essential for estimating location-dependent fade margins, which are useful for the design of wireless communication links for the region. [ABSTRACT FROM AUTHOR]

المؤلفون: Akinbolati, Akinsanmi, J. Agunbiade, Olufemi

المصدر: International Journal of Information Engineering and Electronic Business ; volume 12, issue 3, page 28-39 ; ISSN 2074-9023 2074-9031

الإتاحة: https://doi.org/10.5815/ijieeb.2020.03.04Test

المؤلفون: Akinbolati Akinsanmi

المصدر: International Journal of Digital Information and Wireless Communications. 7:161-172

مصطلحات موضوعية: 0301 basic medicine, 03 medical and health sciences, 030104 developmental biology, Computer science, Tropics, Signal, Digital terrestrial television, Remote sensing

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::9eaf7265817c05e9ab1f46ddb295c173Test
https://doi.org/10.17781/p002336Test