Parabolic equation modeling in horizontally inhomogeneous environments

Abstract

OBJECTIVE Investigate the validity of a parabolic equation (PE) model for predicting radio field strengths in horizontally inhomogeneous environments by performing comparisons between the model and experimental data. RESULTS Excellent agreements were found at VHF and UHF frequencies with good agreement in Sand X-bands. In some cases, the predicted curves for the S-band comparisons underestimated that of the measured data at large ranges. This may be the result of phenomena such as surface roughness, backscatter, etc., not accounted for in the model. Discrepancies may also result from the presence of evaporation ducts not included in the environmental inputs to the model because of a lack of detailed measurements. This would account for lower predicted signal levels at higher frequencies.

Microwave propagation attenuation due to earths atmosphere at very high frequency (VHF) and ultra-high frequency (UHF) bands in Nsukka under a clear air condition

“…Grabner et al (2013) tried to model multipath propagation conditions but had unsatisfactory results. Horizontal spatial distribution of refractivity can be complex (Barrios, 1992), hence vertical refractivity profiles are not enough to describe propagation path under multipath conditions. The results obtained may improve radio communication system in Nigeria since only 25.82% of the entire land mass of Niger state, for example, has television signal coverage (Ajewole et al, 2013).…”

Parabolic Equation Solution of Tropospheric Wave Propagation Using Fem

“…The algorithm has been widely used in many applications [10,11,4]. More specifically, Barrios [12,13] treated horizontally inhomogeneous environments and a terrain model respectively. Craig and Levy [14] applied the Split…”

Atmospheric Refraction and Propagation in Lower Troposphere

“…The parabolic equation method outlined above has been applied frequently to investigate the propagation characteristics on terrestrial (and also on Earth -space) paths under the influence of different refractivity conditions (Barrios, 1992(Barrios, , 1994Levy, 2000) including the ducting layers described in the section 4.2. Users agree the method gives reliable results provided all the relevant details of terrain profile and of refractivity distribution are known and modelled correctly.…”