Open AccessEnhanced spectrum utilisation in dynamic cognitive radios with adaptive sensing
Author(s) -
Treeumnuk Dusadee,
Popescu Dimitrie C.
Publication year - 2014
Publication title -
iet signal processing
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.384
H-Index - 42
eISSN - 1751-9683
pISSN - 1751-9675
DOI - 10.1049/iet-spr.2013.0105
Subject(s) - cognitive radio , computer science , spectrum (functional analysis) , reuse , wireless , overhead (engineering) , radio spectrum , energy (signal processing) , telecommunications , electronic engineering , real time computing , computer network , engineering , mathematics , physics , statistics , operating system , waste management , quantum mechanics
Cognitive Radio (CR) is a new concept in wireless communication systems that aims at enabling dynamic access to the frequency spectrum for unlicensed secondary users (SU) through the reuse of licensed frequencies. Specifically, CR systems are expected to detect idle licensed frequencies (spectrum holes) by applying a spectrum sensing procedure, to take advantage of them for providing service to the SU, and to release them to the licensed primary users (PU) upon request. The duration of the spectrum sensing procedure is an overhead factor that affects the actual utilisation of the spectrum by the CR system and whose adaptation may enhance spectrum utilisation: the less time the CR spends for spectrum sensing and identifying spectrum holes, the more time the spectrum is available for secondary use by the CR. In this paper, we define a formal measure for spectrum hole utilisation in dynamic scenarios and propose a new method for adapting the duration of energy‐based spectrum sensing that improves the detection of PU signals as well as the utilisation of spectrum holes by the SU. The proposed method is illustrated with numerical results obtained from simulations which confirm its effectiveness.