An Inter-Cell Interference Cancellation for Downlink Layer-1/Layer-2 Control Channels in LTE/LTE-Advanced Heterogeneous Networks

Recently, data traffic is explosively growing in cellular mobile communication systems due to the prevalence of smart phones. 3GPP focuses on Pico-cell overlaid HetNet, in which small-cell base stations (pico eNB: pico-cell evolved Node-B) with a low transmit power, are placed at the hot spots within a macro cell in LTE/LTE-Advanced heterogeneous network (HetNet). Cell Range Expansion (CRE) has been proposed as a promising approach to offload the traffic into the pico-cell from the macro-cell. In the CRE scheme, user equipment in pico-cell (pico-cell UE) suffers the strong interference from the macro-cell eNB (macro eNB) to the pico-cell UE, when large CRE offset value is used for received power of reference signal from the pico-cell. In order to mitigate the interference, this paper proposes an inter-cell interference (ICI) canceller on the downlink Layer-1/Layer-2 control channels (L1/L2 Control Channels) for LTE/LTE-Advanced HetNet. This paper evaluates and confirms the effectiveness of the proposed ICI canceller in L1/L2 Control Channels, and associated performance improvements in H-ARQ retransmission in the downlink shared channel (DL-SCH).