Computer simulation of frequency assignment in microcellular system using array antennas

One way of realizing a microcellular system is to place the base station antenna lower than the surrounding buildings. In this case, propagation characteristics are different when the waves travel along streets than when they are obstructed by buildings. Therefore, to estimate spectral efficiency in these microcellular systems, one must know the effective frequency reuse pattern. When the base station antenna is an omni-directional type, received power attenuation has about 1/x/sup 2/ dependence on propagation distance. If selected simple two-element array antennas are arranged as the base station antenna, received power attenuation is less than 1/x/sup 2/ dependence and it is possible to reduce the number of the frequency reuse intervals. The authors simulate, using two different arrangements of base station antenna arrays, and estimate the effective solutions for frequency assignment.