Interference optimization for multicast and broadcast traffics in multi-radio multi-channel WMNs equipped with directional antennas

This paper addresses the interference optimization problem for multicast/broadcast traffics in multi-radio multi-channel wireless mesh networks equipped with directional antennas. Since a directional antenna radiates the major of transmission power to the main-lobe, it can reduce the interference. However, this may increase the number of transmissions. The adaptive directional antenna is an effective tool in controlling the above-mentioned trade-off. The main goal of this paper is to linearly model the multicast/broadcast interference in the presence of directional antennas. In this regard, the authors provide a Mixed Integer Linear Programming (MILP) formulation named “Minimum Interference and Transmission Tree with Directional Antenna (MITT-DA)” to jointly select the best multicast/broadcast routing tree, antenna beam, and transmission channel. The proposed MITT-DA is a comprehensive model which supports both directional and omni-directional antennas. It not only considers wireless broadcast advantage, but also optimizes both inter-flow and intra-flow interferences. Numerical results demonstrate the efficiency of the proposed MILP scheme in terms of the interference and the number of transmissions.