Cross-Polarized Transmission for Interference Avoidance in Femto-Macro Network

Interference issues arising from spectrum reuse in femto-macro networks can result in significant performance degradation in the system. As part of addressing these challenges, this paper proposes cross-polarized data transmission as a potential solution for permitting interference free spectrum reuse in cellular systems. Different from prior art techniques, the paper evaluates a scenario where femtocell network makes use of right hand circular polarization (RHCP) and macrocell network makes use of left hand circular polarization (LHCP) for data transmission so as to aid co-channel allocation. The polarizations being orthogonal to each other due to their sense of rotation ensure isolation between the networks and hence enable both of them to efficiently reuse the same spectral resources simultaneously in the same location. Analytical and simulation results prove that this technology opens the scope for an easily implementable, remarkable opportunity in the context of two-tier femto-macro network that will increase system capacity, spectral efficiency and the probability of successful transmission.