Corrections to “A QoS-Based Cross-Tier Cooperation Resource Allocation Scheme Over Ultra-Dense HetNets”

In our previous analysis in [1], in order to calculate the number of MUEs, we defined ${S_{Hole}}$ to represent the region occupied by MUEs. Due to an editing error, this formula was expressed as ${S_{Hole}} = {\Pr }\{ {N_{S}} = 0\}$ , where the right-hand side of the equation expresses the probability of having no small cell at this point. The correct number of MUEs cannot be obtained by this equation. Next, we give the correct calculation method for the number of MUEs.