Evaluation of angle spread and power balance for design of radio links with directional antennas in multipath environment

Abstract

Development of spatial multiplexing techniques and co-channel operation of different wireless systems require a way to assess the mutual influence of emitted signals. This paper focuses on the signal level evaluation as a function of the path loss that depends on the parameters of a transmitting and receiving antenna in the multipath propagation conditions. The developed procedure uses a multi-elliptical propagation model to estimate a power angular spectrum, which is the basis for evaluation of the received signal power. This procedure provides adaptation of the close-in free space reference distance path loss propagation model by considering parameters of directional parameters. Simulation studies are the basis for assessing the impact of the antenna parameters on the path loss and consequently on the received signal power. The results of these studies show the influence of the width of the main lobe and, most importantly, the direction of the antennas on the level and angular dispersion of the received signals. A comparison of the results for multi-path and free-space propagation conditions demonstrates the viability of the developed procedure for the purposes of predicting power distribution and reception direction.