A Transmit Power Control Based Interference Mitigation Scheme for Small Cell Networks Using Dynamic TDD in LTE-Advanced Systems

This paper proposes a downlink (DL)/uplink (UL) transmission power control (TPC) scheme for dynamic time division duplex (TDD) based small cells under multi-cell environment. In the dynamic TDD, an eNB (evolved node B) selects an adequate UL-DL configuration according to the ratio of DL to UL data bits in each cell. However, in this case, eNB- eNB and user equipment (UE)-UE interferences could be additional interference since the transmission directions can be different among cells. Especially, eNB-eNB interference significantly degrades the UL transmission performances. Therefore, we investigate the DL TPC which is applied to subframes which can be different directions among cells and the benefits to decrease eNB-eNB interference by this scheme. We also investigate the different UL TPC parameters that are applied according to the subframe types in order to alleviate the impact of eNB-eNB interference. Computer simulation confirms that the proposed DL/UL TPC scheme can achieve 21.6 % gain at maximum for UL throughput without significant DL throughput degradation.