Terrain-based propagation model for rural area-an integral equation approach

Abstract

A terrain-based propagation model for vertically polarized radio waves is described, based on the field integral equation for a smooth surface. The model is simplified from a 3D integral equation model to a one-dimensional integral equation by assuming that the surface is magnetically perfectly conducting (a soft surface) with no transverse variations. By assuming no back scattering, the integral equation is turned into a simple integral. The method is tested numerically with known solutions. The integral equatlon model is also applied to actual terrain profiles at four frequencies (144,435, WO, 19oQ MHz), and the results are compared with results from the €lata model and measurements. The standard deviation (STD) of the error is a growing function of frequency, from 3 to 9 dB.

Application of the spectral acceleration forward-backward method for propagation over terrain

“…It is also worth mentioning that, the empirical methods are run on the surfaces Green's function with measurement data or Hata model have been presented [18], [20]. However, those IE methods do not dicretize the surface profile as much as FBSA does and also they use additional approximations, such as neglecting the backscatter.…”

“…Nevertheless, the application of this method to electrically large terrain profiles becomes impractical, due to the computational cost associated. Later on, in [18], a surface integral equation is derived and simplified with some assumptions such as neglecting back scattering and perfect magnetic conductivity, which make the method more efficient but still very time consuming and less accurate. In [19], an integral equation formulation is combined with an iterative version of the MoM, known as the banded matrix iterative approach (BMIA).…”

“…Diffraction losses over 'secondary' obstacles are added to the diffraction loss over the main obstacle [49]. [18], [20]. In this work, using the FBSA as reference solution, the most common propagation prediction models are examined.…”

“…The equation which results specifies 18) which insures that the SDP of a flat surface path is obtained for flat surfaces but a smaller value of δ is used as the surface becomes more rough. In (3.18),…”

Clutter Height Variation Effects on Frequency Dependen Path Loss Models at UHF Bands in Build-Up Areas

“…Therefore, simulated signal path losses are useful planning tools, required by the radio network designer to reach network optimal levels. However, the importance of understanding the terrain features, within the scope of the deploying network, cannot be overruled in the netw planning process (Hviid et al, 1995). Majorly, terrain…”