J4 ›› 2012, Vol. 39 ›› Issue (1): 115-121.doi: 10.3969/j.issn.1001-2400.2012.01.021

• Original Articles • Previous Articles     Next Articles

Performance analysis and optimization of censoring  based cooperative spectrum sensing

LI Meiling1,2;YUAN Chaowei1;TIAN Xinji1;LI Lin1   

  1. (1. School of Info. and Commun. Eng., Beijing Univ. of Posts and Telecomm., Beijing  100876, China;
    2. School of Electronics and Info. Eng., Taiyuan Univ. of Sci. and Tech., Taiyuan  030024, China)
  • Received:2010-09-28 Online:2012-02-20 Published:2012-04-06
  • Contact: LI Meiling E-mail:meiling_li@126.com

Abstract:

In cognitive radio networks, the control channel bandwidth is limited while implementing the cooperative spectrum sensing. Besides, the severe tail sensing problem exists due to the imperfect reporting channels. A censoring based cooperative spectrum sensing scheme is analyzed in this paper, which reduces the control bandwidth by decreasing the average number of sensing bits reported to the fusion center and also the dependence of the detection performance on the cognitive user number. The sensing performance of the proposed scheme is analyzed under both imperfect sensing channels and reporting channels, which indicates that the tail sensing problem could be effectively solved and that the false alarm probability could also be decreased. An optimal cooperative spectrum sensing algorithm is further proposed for maximizing the spectrum access chance of the secondary user by looking for the optimal party of the number of cognitive users and the detection threshold under a certain protective level to the primary user. Simulation results validate the theoretical analysis.

Key words: cooperative spectrum sensing, control bandwidth, fading channel, the false alarm probability, detection threshold

CLC Number: 

  • TN92