Title :
Optimal access strategy for capacity optimization in cognitive radio system
Author :
Elalem, M. ; Lian Zhao
Author_Institution :
Electr. & Comput. Eng. Dept., Ryerson Univ., Toronto, ON, Canada
Abstract :
Well-established fact shows that fixed spectrum allocation policy conveys to the low spectrum utilization. The cognitive radio technique promises to improve the low efficiency. This paper proposes an optimized access strategy combining overlay scheme and underlay scheme for the cognitive radio. We model the service state of the system as a continuous-time Markov model. Based on the service state, the overlay manner or the underlay manner is used by the secondary users. When the primary user is not transmitting and only one secondary user has the requirement to transmit, the secondary system adopts the overlay scheme. When the primary user is transmitting and the secondary users want to transmit simultaneously, an underlay scheme with an access probability is adopted. We obtain the optimal access probability which maximizes the overall system throughput.
Keywords :
Markov processes; cognitive radio; capacity optimization; cognitive radio system; continuous-time Markov model; fixed spectrum allocation policy; low-spectrum utilization; optimal access probability; optimal access strategy; overlay scheme; primary user; secondary users; service state; underlay scheme; Cognitive radio; Interference; Optimized production technology; Receivers; Throughput; Transmitters;
Conference_Titel :
Wireless Communications and Networking Conference (WCNC), 2013 IEEE
Conference_Location :
Shanghai
Print_ISBN :
978-1-4673-5938-2
Electronic_ISBN :
1525-3511
DOI :
10.1109/WCNC.2013.6555106