Cooperative resource allocation scheme for mitigating interference to victim macro UEs in LTE-femtocell networks

Due to the rapid growth of demands for high data rate service in indoor wireless communications, most of the cellular operators are recently interested in femtocell. Femtocell is low power and low cost indoor base station to cover traffics occurred indoors. To install femtocells in cellular networks, interference problem between macrocell and femtocell should be solved since the interference severely degrades the performances of both macrocell and femtocell. In this paper, we propose a cooperative resource allocation scheme for macro evolved nodeB (MeNB) and home eNB (HeNB) to mitigate co-channel interference between macrocell and femtocell in long term evolution (LTE)-Advanced systems. In the proposed scheme, if MeNB recognizes that victim macro user equipments (VMUEs) are suffered by interference from neighbor HeNB, it sends dominant interfering HeNB interference coordination message including a list of candidate subchannels to be allocated to the VMUE. On receiving interference coordination message from MeNB, the interfering HeNB does not use the candidate subchannels for resource allocation to FUEs. Thus, subchannels with high signal-tointerference- plus-noise ratio (SINR) which are not used by dominant interfering HeNB can be allocated to VMUEs. By simulations, we can notice that the proposed scheme can improves the average femtocell throughput and cell-edge user throughput of MUEs compared with power control (PC)- based interference coordination scheme while maintaining the average throughput of macrocells.