Bilişsel radyo ağlarında tayf-bilinçli ve güvenilir dağıtık algılama

The ever increasing demand for wireless communication technologies causes spectrum scarcity and inspires researchers to envision the dynamic spectrum access techniques, i.e., cognitive radio, for efficient utilization of spectrum. Wireless sensor networks (WSN) have been considered as operating at unlicensed bands, however, sensor nodes can access licensed spectrum opportunistically with incorporation of cognitive radio capability. Sensor nodes equipped with cognitive radio emerges a new distributed sensing paradigm, i.e., Cognitive Radio Sensor Networks (CRSN). CRSN alleviates spectrum scarcity via enabling access to and distributed sensing operation over licensed bands. The unique characteristics and research challenges posed by CRSN call for novel networking solutions tailored to realize reliable and energy-efficient distributed sensing.The objective of this research is to design, develop and analyze new advanced communication schemes for reliable and energy-efficient distributed sensing in CRSN.More specifically, a comprehensive performance evaluation of existing transport protocols is performed for reliability and congestion control in CRSN. Delay-sensitive and multimedia communication in CRSN is investigated for various smart grid environments. Furthermore, the spectrum-aware and energy-adaptive reliable transport (SERT) protocol for event delivery is first proposed for CRSN. Next, a new spectrum hole assignment for reliable estimation (SHARE) scheme is proposed to achieve reliable local estimation at actor and reach global consensus among actor nodes. The analysis of dedicated radio utilization for spectrum handoff and efficiency is presented for the cognitive radio networks. Moreover, spectrum-aware and cognitive sensor networks (SCSN) are introduced to address the unique challenges of the smart grid environments for distributed sensing. Finally, Spectrum-aware Underwater Networks are investigated to increase achievable capacity under the limited availability and harsh conditions of the underwater acoustic spectrum.