ICIC in DL and UL with network distributed and self organized resource assignment algorithms in LTE

Inter-cell Interference Coordination (ICIC) has gained much interest in 3GPP's LTE standardization of a new air interface. Due to the new physical layer, interference can now be predicted and avoided on a frequency basis. Such schemes are based on cell wise usage restrictions or preferences of resources. After explaining the general degrees of freedon our "inverted" re-use scheme is represented for the downlink and uplink and its advantages are explained. This is underpinned by 3GPP compliant system simulations. The question of assignment of these restictions or preferences naturally leads to the need of self-organization. For that the concept of semi-static ICIC based on a request-grant mechanism applicable to load balancing is explained. For the static ICIC case with frequency planning a novel, fully distributed algorithm provides an optimized assignment of these resource restrictions to the cells in a self-organizing way. It is capable to resolve sub-optimal aspects as well as comprises methods to detect and prevent possible system instabilites. The presented algorithms lead to an integrated ICIC-SON concept that can be relaized in a multi-cell network solution.