Space Division Multiplexing Aided Opportunistic Spectrum Access for Cognitive Radio Networks

This paper proposes a space division multiplexing aided opportunistic spectrum access (SDM-OSA) scheme for cognitive radio networks by exploiting the spatial signal processing ability provided by multiple antennas. With the scheme, cognitive transmission could be carried out using SDM even though there is no idle spectrum resource available. We make further discussion about antenna requirements for cognitive system. When this demand is met, cognitive transmission could coexist with the primary (licensed) one in one occupied authorized frequency channel with mutual interference eliminated. Compared with traditional cognitive radio which implements OSA to the temporally idle frequency resource, the proposed scheme could effectively improve the performance of cognitive system on the premise that cognitive transmission imposes no interference on the primary.