# AI Optimization-Based Heterogeneous Approach for Green Next-Generation Communication Systems
###### Abstract
SDRs can be remotely configured and managed, making them suitable for deployment in remote or inaccessible locations and reducing the development time and costs associated with hardware redesign. By focusing on software development rather than hardware, SDRs offer a versatile, adaptable, and future-proof solution to a wide range of radio applications, from amateur radio to military communications [8; 9]. As a result, SDR has been an active area of research, where studies have introduced numerous useful models for SDR-based networks in the literature. Another promising solution which can greatly enhance the capacity of next-generation networks and deliver a high throughput is long-term evolution licensed assisted access (LTE-LAA). In LTE-LAA, as shown in Figure 1, the control signal and user's data are carried using primary carriers from the licensed spectrum. However, to boost the data rate, secondary carriers from the unlicensed spectrum are aggregated, using a carrier aggregation technique [10], with the primary carriers to deliver a higher throughput for the user's equipment [11; 12]. The LTE-LAA technique gained approval as part of the 3 rd Generation Partnership Project (3 GPP) Release 13 [13]. However, current LTE-LAA systems face limitations due to their hardware configurations, restricting them to operating solely within an operator's predefined licensed bands alongside a fixed unlicensed band, like the 5 GHz frequency range [12]. Consequently, only the subscribers of a specific operator can take advantage of LTE-LAA's benefits. To extend these benefits to users from various operators, LTE-LAA systems need to support multiple licensed and unlicensed bands, a feat achievable through SDR technology. This advancement would bring advantages to all operators by enhancing revenue and spectrum utilization and benefit users with increased data speeds, improved quality of service, and an overall superior experience quality. Due to their high potential, both SDR and LTE-LAA systems have been studied reasonably well in the literature. However, almost all of the existing approaches treat SDR and LTE-LAA systems separately. In this work, we present a way to couple SDR with LTE-LAA systems. In particular, we present a new SDR-based LTE-LAA architecture for HetNets. We present a resource management solution for this architecture where the goal is to decrease energy consumption and increase the overall throughput. To the best of our knowledge, this is the first work to combine the SDR and LTE-LAA concepts together to maximize the throughput and minimize energy consumption in HetNets. The major contributions of this work can be summarized as follows:  
* We introduce a new architecture for HetNets where the SDR and LTE-LAA concepts complement each other. * We present a resource management scheme for the proposed architecture to maximize network performance with regard to energy consumption and throughput. We formulate this resource management problem as a constrained optimization problem and provide solutions to the optimization problem. * Considering the time complexity of the optimization model, we introduce a heuristic solution which provides good suboptimum solutions. The proposed solution is then benchmarked against existing solutions. The remainder of this paper is structured as follows. The next section explores and discusses previous related works and explains how this research covers gaps in previous research studies. In Section 3, we illustrate and explain our system model and its different parameters, including our communication model, traffic model, and energy model. Moreover, we present the heuristic algorithm and its implementation. Section 4 provides a detailed discussion of the obtained results. In Section 5, we utilize AI techniques to perform a multi-objective optimization of the system. Section 6 states the concluding remarks.