Interference Mitigation through Cross Polarized Transmission in Femto-Macro Network

Femtocells use co-channel allocation with macrocells resulting in cross-tier interference which eventually degrades the system performance. Cross-polarized data transmission is proposed as a potential approach towards improving the spectral efficiency and at the same time permitting co-channel allocation in cellular systems. This letter 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 simultaneous transmissions even when using the same frequency spectrum. The polarizations being orthogonal to each other due to their sense of rotation ensure isolation between the networks and hence promotes interference-free independent operation with better coverage and higher throughput.