  To satisfy the requirement of the fifth generation (5G) mobile communications
that offers an ultra high data rate of 100Mbps to 1Gbps anytime and anywhere,
the coordinated multipoint (CoMP) technique is proposed to mitigate inter-cell
interference to improve the coverage of high data rate services, cell-edge
throughput, and system capacity. However, the joint transmission (JT) CoMP
technique is difficult to be applied in practice due to the critical time
synchronization for multiple coordination links and the bottleneck of backhaul
capacity and radio resource at each small cell base stations (SBSs). Moreover,
since the coordination SBSs in the conditional scheme are entirely separate
from each other, different time of arrivals at the user cause the severe time
synchronization problem. The anisotropic propagation environment in the urban
scenario makes the implementation condition even worse. To tackle these issues,
we propose a novel JT-CoMP scheme with the anisotropic path loss model to
minimize the network backhaul traffic subject to the constraints on the radio
resource and the differences in time of arrivals. Simulation results
demonstrate that the proposed distance-resource-limited CoMP scheme can obtain
the maximum achievable rate with the minimum network backhaul traffic, compared
with existing schemes.
