Fig. 1
From: Optimized sleep strategy based on clustering in dense heterogeneous networks
HetNet system model. We consider a downlink model of HetNet system as shown in Fig. 1. In our model, both of two tiers are considered as cellular network model which consists of radius Rm for macro BSs and Rs for outdoor small BSs, such as macro cells and pico cells. We define the user equipment which connects to the macro BS and small BS as MUE and SUE, respectively. We assume that the UEs are uniformly distributed in the network, and each UE will associate with a macro BS or a small BS