Analysis of Coverage Probability for Cooperative Heterogeneous Network

Heterogeneous network (HetNet) has been studied as a promising technology to boost the system throughput. A new upper boundary of coverage probability (CP) is derived, which is the one of cooperative communication between two base stations (BSs) for downlink HetNet. For the tractability, only the cooperation between two base stations in the same tier of HetNet is considered and a model is set up, in which each randomly chosen user located in the cooperation zones can communicate with at most one couple of BSs, due to the threshold of Signal-to-Interference-Ratio (SIR). Stochastic geometry theory is used to establish the model of HetNet. Simulation results show that the upper boundary of CP for cooperative communication between two BSs in the same tier is decreasing when the SIR threshold for macrocell tier is increasing. The increasing density of low power BSs can increase the performance of cooperative communication in the same tier, as well as reducing the cooperative SIR threshold for low power BSs tier.