Joint Rate and Power Allocation for Cognitive Radios Networks with Uncertain Channel Gains

Conference paper
Part of the Advances in Intelligent Systems and Computing book series (AISC, volume 213)


In this paper, we consider a cognitive radio system with multiple cognitive radio (CR) links in the same neighborhood and propose an opportunistic power control strategy for the CR links. The key feature of the proposed strategy is that, via opportunistically adjusting the CR links’ transmit power, the cognitive user can maximize its achievable transmission rate without degrading the outage probability of the primary user. Since it is difficult to track channel gains instantaneously for dynamic cognitive radio network in practice, the case where only mean channel gains averaged over short-term fading are available is considered. Under such scenarios, we derive interference constraints violation probabilities for primary user so that the interference constraints are only violated with desired limit. The achievable sum rate of the CR links under the proposed power control strategy is analyzed and simulated, taking into the impact of imperfect channel estimation. The robustness of the network system is improved with the proposed scheme.


Cognitive radios networks Uncertain channel gains  Multiple cognitive radio links. 


This work was supported partially by the NSFC under Grant 61104033 and 61174127; the NSFC key Grant with No. 60934003; and the Hebei Provincial Natural Science Fund under Grand F2012203109 and F2012203126. The work of Hongjiu Yang was supported by the National Natural Science Foundation of China under Grant 61203023 and the Postdoctoral Science Foundation of China under Grant 2012M510769, respectively.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Zhixin Liu
    • 1
  • Jinfeng Wang
    • 1
  • Hongjiu Yang
    • 1
  • Kai Ma
    • 1
  1. 1.Institute of Electrical EngineeringYanshan UniversityQinhuangdaoChina

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