Spectrum sensing algorithms for cognitive radio based on polarization vector´s orientation

In this paper, we propose a new blind spectrum sensing method based on the polarization vector´s orientation characteristics of the received signal. We first discuss a spectrum sensing model based on polarization characteristic and develop the directional statistics of a polarization vector which can be used to discriminate the signal and noise. Then, a new polarization sensing algorithm (GLRT-PV) is introduced based on the generalized likelihood ratio test (GLRT) paradigm. Applying the recent advances in directional statistics, we derive closed-form expressions of both the probability of false alarm and the probability of detection. Our simulation results show that the proposed GLRT-PV method exhibits better performance than other existing methods in the case of unknown primary transmitter polarization and/or in the presence of noise power uncertainty.