Efficient spectrum sensing for Cognitive Radio using Cosine Modulated Filter Banks

Future generation wireless communication systems will face the problem of providing efficient spectrum allocation to meet the growing demands of various services. In real-time, the usage of the radio spectrum is rigorously very low and the most of the spectrum is under-utilized. Recent researches in cognitive radio (CR) address these problems. In CR, spectrum sensing is a key factor. Orthogonal Frequency Division Multiplexing (OFDM) is used for multicarrier data transmission. OFDM is found to be a suitable method for spectrum sensing in CR. However, spectral leakage and cyclic prefix (CP) in OFDM reduce the spectrum efficiency. Recently, for data transmission and spectrum sensing, multicarrier filter banks (FBMC) are recently considered as an alternative to OFDM. In this paper, we propose a two-stage spectrum sensing for CR, using Cosine Modulated Filter Banks (CMFB). To design the CMFB, we use two different prototype filters, namely, conventional Finite Impulse Response (FIR) filter and Frequency Response Masking (FRM) filter. The computational complexity of the two different designs are also compared.