Transient Analysis for a Trust-Based Cognitive Radio Collaborative Spectrum Sensing Scheme

Trust-based collaborative spectrum sensing (CSS) methods are particularly vulnerable to secondary user (SU) misbehaviors in the initial stage of the CSS process. It is therefore important to analyze the transient performance of CSS. Expressions for the steady-state average trust values and number of sensing reports transmitted by honest SUs (HSUs) and malicious SUs (MSUs) in a two-phase trust-based energy efficient CSS (EE-CSS) strategy were derived in an earlier paper. In this paper, we derive closed-form expressions for the transient probability distributions and averages of the trust values for HSUs and MSUs in EE-CSS. We also obtain expressions for the transient average number of sensing reports transmitted by HSUs and MSUs to the FC in each phase. The results, verified by simulations, show that these expressions can be used to efficiently evaluate the average number of reports transmitted for a large number of SUs and time slots.