The number of devices connected to the wireless infrastructure is increasing significantly owing to recent developments such as the concept of the Internet of Things (IoT). As a result, the load on wireless networks is increasing, as well as the energy consumption . Therefore, we need to develop energy-efficient mechanisms for resource allocation in wireless networks [1, 2]. The use of a heterogeneous network (HetNet), i.e., a set of small-cell base stations (BSs) overlaid by macrocell base stations (MBSs), can improve the energy efficiency (EE)  of wireless systems, mainly because it brings the transmitters and receivers closer together, thereby combating the path loss effect. However, owing to the proximity of BSs, a co-channel interference (CCI) problem arises which may degrade the overall system performance to a great extent . As a result, CCI management is a crucial task in the next-generation dense HetNets.
In the existing literature, there are several studies regarding EE in HetNets, such as BS placement, load balancing, power control, and dynamic BS sleep–wake mechanisms [4–6]. All these studies provide good solutions to improving EE. However, they are all based on centralized control approaches and need to collect network information in order to make a unified decision. In , a distributed energy-efficient BS ON/OFF switching algorithm based on game theory was proposed. This algorithm considers a utility function combined with the total power consumption and the load on the BSs. Later, by evaluating this utility function, the BSs independently choose a predefined transmission power level. This algorithm can provide improvements in terms of system EE and the overall load reduction compared with conventional approaches in a distributed manner.
Another major issue in wireless communications is the scarcity of wireless channels, i.e., channels in the frequency, time, and space dimensions. Hence, the same channel needs to be reused among BSs, which consequently limits the network capacity owing to the introduced CCI. Dynamic channel assignment (DCA) is an effective technique for reusing the same channel in wireless communications. This technique has been abundantly studied in the literature [8–11]. Previously, we proposed a technique called interference-aware channel-segregation based DCA (IACS-DCA) , in which each BS measures the CCI of different channels on a periodic basis and calculates the average CCI powers.
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