The Simulation of Wave Propagation of Communication Systems in Urban Areas

Abstract

The paper considers the problem of calculating the level of electromagnetic fields wireless communication in urban environments to determine the areas with high signal strength. The analysis of the possible approaches – statistical and deterministic. To solve the problem is proposed to use the radial method. This method is based on decomposition of the electromagnetic field on the rays and finding the rays that connect the transmitting and receiving device, taking into account the diversity of the city. Depending on the algorithm, consideration is taken of the rays, which when reaching the receiver are reflected specularly or diffusely from the walls of buildings and giragira on corners of buildings. In the framework of the algorithm was restricted. The first limitation is that the rays get to the right of the intersection along the main street, the second limitation is due to the fact that the rays go on a minor street. The result of the calculation is represented by the first limiting plane (limitations of the terrain), how overlap of the bounding plane to the plane of the rays. In appearance the bounding planes can be noticed that changing the bounding plane depends only on the number of reflections along the main street. When interpolation is used the method of least squares. The results of calculations based on the developed algorithm and the experimental data taken from literature. The block diagram module calculation of the number of rays. The operation of the calculation module the number of rays is carried out in three stages: using the correlation coefficients, the polynomial is calculated based on the amount of rays, the distance from the transmitter to the receiver, using the correlation coefficients, the polynomial is calculated according to the total power of the power contributed by each beam, based on the polynomial calculated the number of rays given the specified margin of error. The proposed approach using correlation coefficients and approximation based on the least squares method allows to reduce the number of iterations in the calculations of the signal level using the method of ray tracing in several times in comparison with the conventional raytracing.