Rain Induced Cross Polarization on Satellite Communication in Nigeria

P. A. Akanbi, T. V. Omotosho, S. Akinwumi

Abstract


Microwave systems performance on satellite communication link operating above 10 GHz is increasingly degraded by rain when designing telecommunication systems. Cross polarization is one of the major source of signal degradation that affectthe frequency reuse when employed to boost capacity of the channel. The effect of cross-polarization in thirty-seven (37) stations in Nigeria were carried out using 10 years data obtained from Nigeria Meteorological Agency (NIMET) at the look angle from Nigeria Communication Satellite (NigComSat). International Telecommunication Union-Recommendation (ITU-R) model was used to for this study. The stations were grouped into six geopolitical zones in Nigeria which are Southwest (SW), Southeast (SE), South-south (SS), Northcentral (NC), Northwest (NW) and Northeast (NE). The results reveal that cross-polarization discrimination (XPD) become very poor as frequency (at Ku-band, Ka-band, V-band) increases especially at lower percentage of time (such as 0.001%, and 0.01%) unavailability. Hence XPD, at all frequencies is poorer in the southern part of Nigeria SE, SS and SW due to high rainfall rate. The results also show that only Northern part of the country will experience no interference at 0.01% as XPD is over 30 dB ITU-R base line for Ku-band transmission. However, for Ka-band and V-band at 0.001% and 0.01% unavailability of time interference will occur in all stations in Nigeria, but at 0.1% and 1% XPD is over 30 dB for all stations. This study will help in the adequate planning and designing of satellite telecommunication expansion in all the six geopolitical zones in Nigeria.

Keywords


Cross-polarization discrimination; Satellite communication; Frequency; Rainfall rate

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References


A. Ajayi and Kolawole complete the name of author(s), Variation in raindrop size distribution and specific attenuation due to rain in Nigeria, Ann Telecoms. 51 (1-2) (1996), 87 – 93.

G. Brussaard, A metereological model for rain induced cross-polarization, IEEE Transection on Antenna Propagation Ap-24 (1976), 5 – 11.

M. Camara, S.O. Bashir and F.N.M. Isa, Prediction of rain induced cross-polarization at microwave and millimeter wave bands in Guinea, 2014 International Conference on Computer and Communication Engineering (ICCCE), (2015), 1 – 25 doi:10.1109/ICCCE.2014.58.

David A. de Wolf , Based on the Law-Parrsons raindrop size distribution, Radio Science 36 (4) (July/August 2001), 639 – 642.

European Space Agency (ESA), Evaluating Cloud Microphysics from NICAM against CloudSAT and CALIPSO (2013).

International Telecommunication Union-Recommendation (ITU-R), Propagation data and prediction methods required for the design of earth-space telecommunication systems, International Telecommunication Union P612-8 (2015), 25 – 27.

J. Sen, Estimation of cross-polarization due to rain over some station in India, Indian Journal of Radio and Space Physics 36 (7) (2007), 276 – 287.

T.V. Omotosho, Theoretical study on rain induced cross polarization and rain rate in tropical region, Federal University of Technology, FUTA Akure., M. Tech. Thesis (2003).

M. Saunders, Cross polarization due to rain at 18 GHz and 30 GHz, Trans Antenna propagation, IEEE Trans. Antenna Propagation AP-19 (1971), 273 – 277.

Tan and Thurai, Calculation of XPD spread for 20 GHz fixed satellite system using rain microstructure information, Indian Journal of Space Physics 12 (2009), 276 – 287.

M. Van de Kamp, Depolarization due to rain: XPD-CPA relation, International Journal on Satellite Communication 9 (1999), 285 – 301.




DOI: http://dx.doi.org/10.26713%2Fjims.v9i2.739

eISSN 0975-5748; pISSN 0974-875X