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On the Capacity of Underlay Cognitive Radio Networks Over Shadowed Multipath Fading Channels

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Abstract

Cognitive radio is of great interest for current and future wireless communications. In this paper, the capacity of underlay cognitive radio networks is studied where closed-form expressions for both the ergodic capacity and the outage capacity of the secondary user (SU) are derived. The obtained results reveal new details on the joint effect of multipath fading and shadowing on the capacity of the SU where the increase of the ergodic capacity and degradation of the outage capacity due to heavy shadowing are demonstrated and quantified. Furthermore, the analytical results are verified by Monte-Carlo simulations for different fading scenarios.

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References

  1. FCC.: Spectrum policy task force report. Report of Federal Communications Commission. Tech. Rep. 02-135 (2002)

  2. Mitola, J.; Maguire, G.Q.: Cognitive radio: making software radios more personal. IEEE Trans. Inf. Theory 6(4), 13–18 (1999)

    Google Scholar 

  3. Goldsmith, A.; Jafar, S.A.; Maric, I.; Srinivasa, S.: Breaking spectrum gridlock with cognitive radios: an information theoretic perspective. Proc. IEEE 79(5), 894–914 (2009)

    Article  Google Scholar 

  4. Gastpar, M.: On capacity under receive and spatial spectrum-sharing constraints. IEEE Trans. Inf. Theory 53(2), 471–487 (2007)

    Article  MATH  MathSciNet  Google Scholar 

  5. Ghasemi, A.; Sousa, E.S.: Fundamental limits of spectrum-sharing in fading environments. IEEE Trans. Wirel. Commun. 6(2), 649–658 (2007)

    Article  Google Scholar 

  6. Kang, X.; Liang, Y.C.; Nallanathan, A.; Garg, H.K.; Zhang, R.: Optimal power allocation for fading channels in cognitive radio networks: ergodic capacity and outage capacity. IEEE Trans. Wirel. Commun. 8(2), 940–950 (2009)

    Article  Google Scholar 

  7. Salhab, A.M.; Zummo, S.A.: Spectrum-sharing AF relay networks with switch-and-examine relaying and multiple primary users using orthogonal spectrums. Arab. J. Sci. Eng. 41(2), 513–525 (2016)

    Article  Google Scholar 

  8. Fredj, K.B.; Aissa, S.; Musavian, L.: Ergodic and outage capacities of relaying channels in spectrum-sharing constrained systems. IET Commun. 7(2), 98–109 (2013)

    Article  MATH  MathSciNet  Google Scholar 

  9. Zhang, X.; Zhang, Y.; Yan, Z.; Xing, J.; Wang, W.: Performance analysis of cognitive relay networks over nakagami fading channels. IEEE J. Sel. Areas Commun. 33(5), 865–877 (2015)

    Article  Google Scholar 

  10. Bithas, P.S.; Efthymoglou, G.P.; Kalivas, D.S.: Outage probability of cognitive relay networks over generalized fading channels with interference constraints. Proc. Comput. Sci. 40, 84–91 (2014)

    Article  Google Scholar 

  11. Kamga, G.N.; Fredj, K.; Aïssa, S.: Multihop cognitive relaying over composite multipath/shadowing channels. IEEE Trans. Veh. Tech. 64(8), 3807–3812 (2015)

    Article  Google Scholar 

  12. Miridakis, N.I.: On the ergodic capacity of underlay cognitive dual-hop af relayed systems under non-identical generalized-k fading channels. IEEE Commun. Lett. 19(11), 1965–1968 (2015)

    Article  Google Scholar 

  13. Tran, H.; Duong, T.Q.; Zepernick, H.J.: Performance analysis of cognitive relay networks under power constraints of multiple primary users. In: Proceedings IEEE GLOBECOM, Houston, U.S.A, pp. 1–6 (2011).

  14. Duong, T.Q.; Yeoh, P.L.; Bao, V.N.Q.; Elkashlan, M.; Yang, N.: Cognitive relay networks with multiple primary transceivers under spectrum sharing. IEEE Signal Process. Lett. 19(11), 741–744 (2012)

    Article  Google Scholar 

  15. Hyadi, A.; Benjillali, M.; Alouini, M.S.; da Costa, D.: Performance analysis of underlay cognitive multihop regenerative relaying systems with multiple primary receivers. IEEE Trans. Commun. 12(12), 6418–6429 (2013)

    Google Scholar 

  16. Salhab, A.M.; Zummo, S.A.: Multiuser cognitive networks with nth-best user selection and imperfect channel estimation. Arab. J. Sci. Eng. 12(39), 8979–8987 (2014)

    Article  Google Scholar 

  17. Simon, M.K.; Alouini, M.S.: Digital Communication over Fading Channels. Wiley, Hoboken (2005)

    Google Scholar 

  18. Al-Ahmadi, S.: The gamma-gamma signal fading model: a survey [wireless corner]. IEEE Antennas Propag. Mag. 56(5), 245–260 (2014)

    Article  Google Scholar 

  19. Abdi, A.; Kaveh, M.: A comparative study of two shadow fading models in ultrawideband and other wireless systems. IEEE Trans. Wirel. Commun. 10(5), 1428–1434 (2011)

    Article  Google Scholar 

  20. Al-Ahmadi, S.; Yanikomeroglu, H.: On the approximation of the generalized-k distribution by a gamma distribution for modeling composite fading channels. IEEE Trans. Wirel. Commun. 9(2), 706–713 (2010)

    Article  Google Scholar 

  21. Gradshteyn, I.S.; Ryzhik, I.M.: Table of Integrals, Series and Products. Elsevier, Amsterdam (2007)

    MATH  Google Scholar 

  22. Goldsmith, A.; Varaiya, P.P.: Capacity of fading channels with channel side information. IEEE Trans. Inf. Theory 43(6), 1986–1992 (1997)

    Article  MATH  MathSciNet  Google Scholar 

  23. Brychkov, Y.A.; Marichev, O.; Prudnikov, A.: Integrals and Series, Vol 3: More Special Functions. Gordon and Breach Science Publishers, Philadelphia (1986)

    MATH  Google Scholar 

  24. Kostic, P.M.: Analytical approach to performance analysis for channel subject to shadowing and fading. IEE Proc. Commun. 152(6), 821–827 (2005)

    Article  Google Scholar 

  25. Tse, D.; Viswanath, P.: Fundamentals of Wireless Communication. Cambridge University Press, Cambridge (2005)

    Book  MATH  Google Scholar 

  26. Efthymoglou, G.P.: On the performance analysis of digital modulations in generalized-K fading channels. Wirel. Pers. Commun. 65(3), 643–651 (2012)

  27. Papoulis, A.; Pillai, S.U.: Probability, Random Variables, and Stochastic Processes, 2nd edn. Tata McGraw-Hill Education, New York City (2002)

    Google Scholar 

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Correspondence to Majid H. Khoshafa.

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Khoshafa, M.H., Al-Ahmadi, S. On the Capacity of Underlay Cognitive Radio Networks Over Shadowed Multipath Fading Channels. Arab J Sci Eng 42, 5191–5199 (2017). https://doi.org/10.1007/s13369-017-2688-7

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  • DOI: https://doi.org/10.1007/s13369-017-2688-7

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