Scalable LTE interference mitigation solution for HetNet deployment

Interference management has become an important concern for the wireless community over the years. This is especially important in the context of LTE, which relies on OFDMA and dense frequency reuse. Different techniques for inter-cell interference coordination are available in literature but most of them make use of static methods, which cannot adapt to a load changing network or heavily complex centralized systems which present an obstacle for future scalability. Furthermore the addition of heterogeneous components, such as femtocells, has incremented the inter-cell interference problem even more. Given the unpredictable nature of femtocells and the fact that no communication mechanism is envisioned between macrocells and femtocells, the inter-cell interference problem needs to be addressed in two separate ways. In this paper we analyze a heterogeneous LTE OFDMA downlink network and we propose a low-complexity, distributed interference mitigation method which is aware of network load and propagation conditions. The method is fully scalable and addresses the macro-to-macro and the femto-to-macro interference separately. The proposed method makes use of the iterative Hungarian algorithm, which effectively reduces interference and enhances the quality of service of starved user when compared to other state of the art solutions.