Cognitive radio: a study of the role of KL distance function in energy detection scheme

Abstract

Cognitive radio has been identified as a frontline technology in wireless communication domain where unlicensed spectrum users can utilize unused licensed frequency bands without affecting the licensed users' transmission process. Spectrum hole detection is the primary requirement to fulfill this objective. Usually energy detector is used for its easy realization. In this method, a test statistic is formulated by Neyman-Pearson lemma and compared with a threshold to make a decision regarding the vacancy of a frequency band. This paper shows an alternative test statistic formulation by Kullback-Leibler distance function and it is established that the proposed approach gives much better result in low SNR zone with comparatively lesser number of samples. The performances are adjudicated by false alarm probability and detection probability. Numerical results are provided to validate the proposition.