Chapter 15
Enhanced Inter-Cell Interference Coordination (eICIC)
On an LTE network, the frequency resources of one cell can be reused by the adjacent neighboring cells to maximize efficiency of frequency spectrum usage, which means that the frequency reuse factor is typically 1. When such a complete frequency reuse operation is utilized, inter-cell interference cannot be avoided.
Figure 15.1 illustrates the inter-cell interference between adjacent cells in an OFDMA network [1], where the resource blocks allocated to the UE in one cell overlap with the resource blocks allocated to another UE in another cell in the time and frequency domains. The overlapping resource blocks generate mutual interference to both UEs.
Figure 15.1 Inter-cell interference by radio resource block collision
Such inter-cell interference lowers the Signal to Interference plus Noise Ratio (SINR) associated with these resource blocks. As a result, the ratio of transmission failure increases and then the resource utilization is impacted badly. The impact of inter-cell interference would be more severe if a UE were located at a cell edge where the measured level of the serving cell becomes almost comparable to that of adjacent neighboring cells. Unless a suitable mechanism is applied to manage such inter-cell interference, target QoS cannot be guaranteed.
3GPP introduced the following Inter-Cell Interference ...
