On energy minimization in cooperative spectrum sensing using LRT in presence of emulation attack

Energy efficient and reliable spectrum sensing become essential in cooperative cognitive radio networks. However, cooperation in spectrum sensing (SS) is often vulnerable to several security threats; one such operation is primary user emulation attack (PUEA). To address the issues, an optimization framework is developed in this work to minimize the energy consumption in cooperative spectrum sensing (CSS) in presence of PUEA using log-likelihood ratio test (LLRT) at the fusion center (FC) while maintaining a target sensing reliability. Sensing reliability is characterized by a high detection probability and a low false alarm probability. FC is assumed to be equipped with multiple antennas, where each one receives signal from a particular secondary user along-with PUEA signal. FC computes a global test statistics by combining all log-likelihood ratios (LLRs). Simulation results highlight performance gain in energy consumption at low sensing duration over the existing energy detection based approach.