Interference control using polarization in directive 60 GHz mesh networks

In this paper a directive mesh network operating in the 60 GHz unlicensed band is considered for backhaul support for a small cell mobile network in an urban environment and interference between network links is analyzed. It is observed that while non-line-of-sight stations are adequately isolated by antenna directivity, interference can affect link performance in links that fall in line with each other, namely, line-of-sight links. Seeing as back-to-back links may occur in the proposed network between stations situated within long straight streets, the resulting interference can cause a decrease in network capacity by preventing simultaneous transmission on links. Here, the use of orthogonal polarizations is proposed as a method for controlling interference in LOS links allowing for simultaneous function of a higher number of links and thus better utilization of channel resources and ultimately achieving higher network throughput.