Impact Assessment of Elevation Angles on Signal Propagation at VHF and UHF Frequencies for Improved Rural Telephony

Main Article Content

Ubong Ukommi
Emmanuel Ubom

Abstract

Rural telephony is challenging in the remote part of Nigeria due to inadequate telecommunication infrastructure, exorbitant cost of communication systems and poor road network for extension of fiber network. These factors constitute poor or no cellular network services in many villages. Alternatively, using Television White Space (TVWS) technology to facilitate telephony services in the rural areas through Ultra High Frequency (UHF) and Very High Frequency (VHF) spectrum is cost effective. Thus, this research investigates impact of elevation angle on signal propagation at UHF/VHF frequencies. The experimental test scenarios took measurements of received signal quality performance at different elevation angles and transmit power levels to obtain more stable results for substantive inference. The experimental test scenario considered a communication link, operating at UHF frequency of 436 MHz. During the experiment, azimuth and propagation loss for the communication link were kept constant while the receiving antenna elevation angles were varied to assess the impact of elevation angles. The assessment examined results obtained during the experiment. Comparing the received signal quality performance at zero (00) elevation angle, it has been observed that the received signal quality improves when the transmit power allocation increases. Results further show that for a given transmit power level of 34dBm, at zero (00) elevation angle test configuration, received signal quality performance of 1.80 dB, 6.90 dB at 300 elevation angle and 10.9 dB at 600 elevation angle were obtained, compared to improved quality performance of 11.8 dB at 00 elevation angle, 19.90 dB at 300 elevation angle and 24.92 dB at 600 elevation angle when the transmit power level was increased to 46.98 dBm. It is deduced from the experimental results that elevation angle of receiving antenna has significant influence on the received signal quality performance. This insight is very useful in the design and network planning of rural telecommunication services using TVWS frequencies for improved rural broadband penetration.

Article Details

How to Cite
Ukommi, U., & Ubom, E. (2023). Impact Assessment of Elevation Angles on Signal Propagation at VHF and UHF Frequencies for Improved Rural Telephony. ABUAD Journal of Engineering Research and Development, 6(2), 136-142. https://doi.org/10.53982/ajerd.2023.0602.13-j
Section
Articles

References

[1] Osseeiran, A., Parkvall, S., Peterson, P., Zaidi, A., Magnusson, S. & Balachandran (2020). 5G Wireless Access: An Overview. White paper, Ericsson Research, Stockholm.
[2] Zhang, W., Yang, G., & Yao, C. K. (2018). TV White Space and Its Applications in Future Wireless Networks and Communications: A Survey. IET Communications Journals, 12(20), 2521-2532.
[3] G.Ding, Wang, J., Wu, Q. Yan Y, Song, F. & Tsiftsis, T.A. (2016). Cellular-Based-Station-Assisted Device-to-Device Communication in TV White Space. IEEE Journal on Selected Areas in Communications, 34 (1), 107-121.
[4] Flores, A., Guerra, R., Knightly, E., Ecclestine, P. & Pandley, S. (2015). A Standard for TV White Space Spectrum Sharing. IEEE Communications Magazine, 51(10), 92-100.
[5] Ofcom, (2015). Ïmplementing TV White Space. Retrieved from https://www.ofcom.org.uk
[6] Ubom, E., Akpanobong, A. & Ukommi, U. (2021). Spectrum Occupancy in Rurl Nigeria: A Case for a liightly Licensed Spectrum Band for Rural Broadband Enhancement. International Journal of Computer and Information technology, 11(4), 81-99.
[7] Ukommi, U. (2020). Media Motion-based Resource Distribution for Mobile Video Networking. Nigerian Journal of Technology (NIJOTECH), 39 (4), 1185-1189.
[8] Ukommi, U., Ubom, E. & Ikpaya, I. (2021). Ground Station Design for Satellite and Space technology Development'. American Journal of Engineering Research (AJER), 10 (8), 12-19.
[9] International Telecommunication Union. (2016). Systems and Networks for Fixed-Satellite Service, Mobile-Satellite Service, Broadcasting Satellite Service and Radiodetermination-Satellite Service, Radiocommunication Study Group. Retrieved from https://www.itu.int/en/ITU-R/study-groups.
[10] Saunders, S. & Aragon-avala, A. (2007). Antennas and Propagation for Wireless Communication Systems, 2nd Ed, John Wiley and Sons Limited, Sussex, England.
[11] Choi, T., Stevenson, T. & Lightsey, E. (2017). Reference Ground Station Design for University Satellite Missions with Varying Communication Requirements. Georgia Institute of Technology, Atlanta, American Institute of Aeronautics and Astronautics, Texas, United State of America, 1(1), 1-8.
[12] Ogunjide, S., Ohize, H. & Usman, A. (2020). Suitable Propagation Models for 2.4GHz Wireless Networks; Case Study of Gidan Kwano Campus, FUT Minna, ABUAD Journal of Engineering Research and Development (AJERD), 3(1), 156-165.
[13] Ukommi, U., Ubom, E. & Abraham, I. (2020). Outdoor 2.4GHz band Wifi Networks Performance Characterisation. International Journal of Engineering and Technical Research, 9(8), 207-212.
[14] Adeniji, K., IKpeze, O., Ejidokum, T. & Alli, K. (2017). Analysis of Propagation Models for Base station Antenna: A case Study of Ado-Ekti, Nigeria. ABUAD Journal of Engineering Research and Development (AJERD), 1(1), 124-129.
[15] Ekanem, H.H., Ubom, K. E. & Ukommi U. (2022). Analysis of Rain Attenuation for Satellite Communication in Akwa Ibom State, Nigeria. The Nigerian Institute of Electrical and Electronic Engineers (NIEEE) Proceedings of the International Conference and Exhibition on Power and Telecommunication (ICEPT 2022), 23-34.
[16] Olurope, O., Ukommi U. & Udoh, R. (2022) Comparative Coverage and Horizon Plane Analysis for LEO, MEO, GEO and HEO Satellites. Journal of Multidisciplinary Engineering Science and Research (JMESR), 1(2), 54-56.
[17] Bazdresch, M., Velayudhan, S. & W. Johnson, (2016). A Satellite Ground Station for Teaching Digital and Wireless Communications, IEEE Frontiers in Education Conference, United States of America, 1(1), 1-4
[18] Udoh, R. & Ukommi, U. (2022). Determination of Visibility Time for Geodesic Satellites Orbiting the Earth on Circular Orbit Subject to Minimum Zenith Angle Restriction. International Multilingual Journal of Science and Technology (IMJST), 7(6), 5435-5443.