Virtual HetNet: A backhaul free pico cell implementation solution

To satisfy the fast growing throughput requirement in certain hot spot areas, pico cells are suggested to be deployed within the Macro cell coverage, forming a heterogeneous network (HetNet). However, it is difficult to deploy new sites in dense populated urban cities for new deployment and new fiber for the corresponding backhaul requirement. To solve these problems, a new architecture is proposed in this paper that a pico cell can be formed via a special antenna collocated with macro base station. With this backhaul free virtual HetNet (vHetNet) architecture, it is easy to realize CoMP and/or joint processing between the macro cells and picocells. The joint data transmission and control information transmission in such vHetNet is also discussed. The results from the field testbed trial have verified that the proposed backhaul free solution can provide promising capacity gain while squeezing out the need to find a new location to install pico cell base station(s).