Energy efficiency analysis of cooperative spectrum sensing: A malicious user's perspective on Byzantine attack

As wireless communication technology advances rapidly, spectrum resource scarcity has become a major challenge for wireless devices and applications. To address the issue of spectrum resource scarcity, cognitive radio (CR) technology was developed. Its objective is to utilize spectrum sensing to detect the state of the authorized/primary user (PU), allowing the unauthorized/secondary users (SUs) to dynamically access the spectrum resources. Furthermore, cooperative spectrum sensing (CSS) is designed to increase the PU signal's detection accuracy but also suffers from Byzantine attack from malicious users (MUs). To acquire a more profound insight of the detrimental effects of a Byzantine attack on CSS, we establish a probabilistic model that characterizes malicious actions in an infrastructure-based cognitive radio network (CRN). Building upon this new perspective of MUs, we conduct a comprehensive analytical study to investigate the achievable throughput, energy consumption (EC) of spectrum sensing and data transmission in the CSS process. Moreover, the close-formed expressions of energy efficiency (EE) with respect to the attack parameters are derived and the impact analysis of Byzantine attack on EE are also provided under the four scenarios. Finally, a series of numerical simulation results demonstrate that provides a guideline for a more secure and robust Byzantine defense strategy in the future.