Spatio-frequency domain opportunistic access in CR-MIMO system based on primary transmission mode information
Liyuan Xiao · Journal of Communications · 2012
An opportunistic spatio-frequency access(OSFA) strategy for CR-MIMO system was designed.When spec-trum holes exist,cognitive service was implemented applying overlay approach.While there was no idle spectrum avail-able,primary transmission mode information(PTMI) and inter-system interference channel information were exploited.And cognitive service was implemented using underlay approach.The method utilizes both spatial correlation and ei-genmode transmission gain in spatial resource quality evaluation.Consequently,selection diversity of both authorized channel and cognitive eigenmode was achieved.Moreover,PTMI based signal processing reduced the antenna require-ment for cognitive system as well as the power loss of cognitive signal.Simulation results indicate that the proposed method could achieve significant improvement of cognitive service and near-optimal cognitive throughput on the premise that no interference is imposed on the primary.