Optimal Layout of Three-sector Pico-BS with 3D-BF in mmWave HetNets

Heterogeneous networks (HetNets) incorporating picocells operating in the millimeter-wave (mmWave) bands offer higher user throughput due to the availability of large signal bandwidths. Downlink three-dimensional beamforming (3D-BF) is a promising technique for improving the received SINR at user terminals (UEs). We have proposed a three-sector pico-BS equipped with 3D-BF in mmWave HetNet and have investigated its effectiveness thus far. This paper discusses an optimal layout of the proposed pico-BS in HetNet from the perspective of the user throughput. Using system-level computer simulations, the average user throughput are clarified against four types of pico-BS layout. From the simulation results, we confirmed that distributing the pico-BS over an area farther from the dominant macro-BS in HetNet can improve the user throughput, however, if the distributing area is too far away, the user throughput deteriorates due to the interference between pico-BSs in adjacent cells.