User sensing based on MIMO cognitive radio sensor networks

In this paper, we consider cooperative spectrum sensing in OFDM based on energy detection in MIMO cognitive radio sensor networks. Soft combination of the observed energy values from different cognitive radio users is investigated. Square-law-combining (SLC) is theoretically proved to be nearly optimal in low signal-to-noise ratio (SNR) region, an usual scenario in the context of MIMO cognitive radio sensor networks. In particularly, the OFDM based MIMO cognitive radio sensor networks detect the primary user OFDM signal, where CR receiver is equipped with multiple antennas based energy detector. We observed significant improvement in primary user detection with SLC based energy detection at the MIMO cognitive radio sensor networks.