AUTHORS: Jing Yang, Lei Chen, Chunxiao Li, Kostas P. Peppas, P. Takis Mathiopoulos

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ABSTRACT: In this paper, a dual-hop cognitive amplify-and-forward (AF) relay network subject to independent nonidentically distributed (i.n.i.d.) η − µ fading channels is investigated. In the considered network, secondary users (SUs) including one secondary user source (SU-S) and one secondary user relay (SU-R) are allowed to share the same spectral resources with the primary user (PU) simultaneously under the premise that the quality of service (QoS) of PU can be guaranteed. In order to guarantee the QoS of PU, the maximum interference power limit is considered to constraint the transmit powers at SU-S and SU-R. For integer-valued fading parameters, a closedform lower bound for the outage probability (OP) of the considered networks is obtained, whereas the lower bound in integral form for the OP is derived for arbitrary-valued fading parameters. For the special case of the generalized η − µ fading channels, such as Nakagami-m fading channels, the analytical results become the previous published results. In order to obtain further insights on the OP performance, asymptotic expressions for the OP at high SNRs are derived. From the asymptotic results, we also reveal that the diversity gain of the secondary network is only determined by the fading parameters of the secondary network, whereas the primary network only affects the coding gain. Finally, simulation confirms the correctness of our analysis

KEYWORDS: Outage probability (OP), amplify-and-forward (AF), cognitive relaying networks (CRN), η−µ fading, spectrum sharing

REFERENCES:

[1] T. Q. Duong, V. N. Q. Bao, and H. -J. Zepernick, Exact outage probability of cognitive AF relaying with underlay spectrum sharing, Electron. Lett., Vol. 47, No. 17, 2011, pp. 1001-1002.

[2] W. Xu, J. Zhang, P. Zhang, and C. Tellambura, Outage probability of decode-and-forward cognitive relay in presence of primary users interference, IEEE Commun. Lett., Vol. 16, No. 8, 2012, pp. 1252-1255.

[3] V. N. Q. Bao, T. Q. Duong, and C. Tellambura, On the performance of cognitive underlay multihop networks with imperfect channel state information, IEEE Trans. Commun., Vol. 61, No. 12, 2013, pp. 4864-4873.

[4] T. Q. Duong, D. B. da Costa, M. Elkashlan, and V. N. Q. Bao, Cognitive amplify-and-forward relay networks over Nakagami-m fading, IEEE Trans. Veh. Technol., Vol. 61, No. 5, 2012, pp. 2368-2374.

[5] M. H. Xia and S. A¨ıssa, Cooperative AF relaying in spectrum-sharing systems: Performance analysis under average interference power constraints and Nakagami-m fading, IEEE Trans. Commun., Vol. 60, No. 6, 2012, pp. 1523-1533.

[6] J. L. Wang, Z. S. Zhang, Q. H. Wu, and Y. Z. Huang, Outage analysis of cognitive relay networks with interference constraints in Nakagami-m channels, IEEE Wireless Commun. Lett., Vol. 2, No. 4, 2013, pp. 387-390.

[7] F. R. V. Guimara˜es, D. B. da Costa, T. A. Tsiftsis, C. C. Cavalcante, and G K Karagiannidis, Multiuser and multirelay cognitive radio networks under spectrum-sharing constraints, IEEE Trans. Veh. Technol., Vol. 63, No. 1, 2014, pp. 433-439.

[8] M. D. Yacoub, The κ − µ distribution and the η − µ distribution, IEEE Ant. and Propag. Mag., Vol. 49, No. 1, 2007, pp. 68-81.

[9] M. D. Yacoub, The η −µ distribution: A general fading distribution, in Proc. IEEE VTC, Boston, MA, USA, Sep. 2000, pp. 872-877.

[10] D. Morales-Jimenez and J. F. Paris, Outage probability analysis for η − µ fading channels, IEEE Commun. Lett., Vol. 14, No. 6, 2010, pp. 521-523.

[11] H. Yu, G. Wei, F. Ji, and X. Zhang, On the error probability of cross-QAM with MRC reception over generalized η − µ fading channels, IEEE Trans. Veh. Technol., Vol. 60, No. 6, 2011, pp. 2631-2643.

[12] K. P. Peppas, G. C. Alexandropoulos, and P. T. Mathiopoulos, Performance analysis of dual-hop AF relaying systems over mixed η − µ and κ − µ fading channels, IEEE Trans. Veh. Techno., Vol. 62, No. 7, 2013, pp. 3149-3163.

[13] N. Y. Ermolova, Moment generating functions of generalized η − µ and κ − µ distributions and their applications to performance evaluation of communication systems, IEEE Commun. Lett., Vol. 12, No. 7, 2008, pp. 502-504.

[14] K. P. Peppas, F. Lazarakis, T. Zervos, A. Alexandridis, and K. Dangakis, Sum of non-identical independent squared η-µ variates and applications in the performance analysis of DS-CDMA systems, IEEE Trans. Commun., Vol. 9, No. 9, 2010, pp. 2718-2723.

[15] I. S. Gradshteyn and I. M. Ryzhik, Table of Integrals, Series, and Products, 7th edition, Academic Press, 2007.

[16] L. Debnath, Integral transforms and their applications, CRC Press, 1995.

[17] A. P. Prudnikov and Y. A. Brychkov and Q. I. Marichev, Integrals and Series: Special Functions, 1st ed. Boca Raton, FL, USA: CRC, 1992.