Multi-taper and MIMO techniques for spectrum sensing in cognitive radio

Frequency spectrum sensing is a key and challenging task of modern wireless communication systems. Cognitive radio (CR) has recently been envisioned as an intelligent platform capable of achieving better spectrum sensing and, hence, promotes efficient spectrum utilization. The multi-taper method (MTM) is a good candidate to achieve such a requirement. This paper focuses on the application of MTM spectrum sensing using multiple antenna arrangement environments. Maximal ratio combining (MRC) is employed as near to optimum candidate for diversity combining technique to process the spectrum estimate at the output of multiple receive antennas. Analysis and results show that such an arrangement provides better performance compared to the single antenna option under additive white Gaussian noise (AWGN) conditions. Moreover, a proposal for a new and simple approach to derive the decision statistical measures reveals that the probability density functions (PDFs) share common factors in both time and frequency domains. Furthermore, transmit antenna diversity also assumes direct positive influence on the spectrum sensing performance.