Title :
An LLR-Based Cognitive Transmission Strategy for Higher Spectrum Reutilization
Author :
Haghighi, Kasra ; Ström, Erik G. ; Agrell, Erik
Author_Institution :
Dept. of Signals & Syst., Chalmers Univ. of Technol., Gothenburg, Sweden
Abstract :
Reutilization of the spectrum licensed to services with low occupancy is of great interest for cognitive radios (CRs). To achieve this goal, we introduce a simple hidden Markov model which captures the primary users activity, signal uncertainties, and noise. For evaluating the performance of any CR, two new criteria are presented entitled spectrum utilization ratio (UR) and interference ratio (IR). Based on this model and new measures, a new a- posterior log-likelihood-ratio based CR is designed and implemented. Its performance is compared with standard energy- detection based spectrum-sensing CR. We demonstrate more than 300% increase in UR for up to 1% allowed interference at the SNR of -5dB.
Keywords :
cognitive radio; hidden Markov models; maximum likelihood estimation; radio spectrum management; radiofrequency interference; LLR-based cognitive transmission strategy; a-posterior log-likelihood-ratio based CR; cognitive radio; hidden Markov model; higher spectrum reutilization ratio; interference ratio; signal uncertainty; standard energy detection based spectrum-sensing CR; Cognitive radio; Computational modeling; Hidden Markov models; Interference; Sensors; Signal to noise ratio;
Conference_Titel :
Global Telecommunications Conference (GLOBECOM 2011), 2011 IEEE
Conference_Location :
Houston, TX, USA
Print_ISBN :
978-1-4244-9266-4
Electronic_ISBN :
1930-529X
DOI :
10.1109/GLOCOM.2011.6133865
