Collaborative wideband sensing for cognitive radios

摘要: Cognitive radio (CR) has recently emerged as a promising technology to revolutionize spectrum utilization in wireless communications. In CR network, secondary users continuously sense the spectral environment and adapt transmission parameters opportunistically use available spectrum. A fundamental problem for CRs is sensing; need reliably detect weak primary signals of possibly different types over targeted wide frequency band order identify holes opportunistic Conceptually practically, there growing awareness that collaboration among several can achieve considerable performance gains. This article provides an overview challenges possible solutions design collaborative wideband sensing networks. It argued make signal processing gains at physical layer mitigate strict requirements on front-end exploit spatial diversity through network cooperation significantly improve reliability.