Operator Assisted Cognitive Radio and Dynamic Spectrum Assignment with Dual Beacons - Detailed Evaluation

Dynamic spectrum assignment refers to a new approach for radio regulation. Whereas today either command-and-control licensing, or alternatively unlicensed bands are used to coordinate the radio spectrum utilization, it is envisioned to coordinate the spectrum utilization in a more flexible way with the help of dynamic spectrum assignment. With this new approach, radio systems will share spectrum either horizontally with distributed spectrum allocation such as listen-before-talk and equal rights to access the radio spectrum, or vertically, where so-called primary radio systems have higher priority to access the radio spectrum than the so-called secondary radio systems. Horizontal and vertical spectrum sharing are often discussed in the context of opportunistic spectrum usage and cognitive (secondary) radio. To guarantee the spectrum access priorities when spectrum is shared, and to coordinate the vertical spectrum sharing between primary and cognitive radio systems, beaconing concepts are often proposed but criticized for their poor reliability in hidden station scenarios. In this paper, we discuss an improved beaconing concept that is based on operator assistance with two instead of one single beacon. Our analysis illustrates that our proposed dual beacon concept provides high flexibility and at the same time improves the reliability of spectrum coordination