Alper KARAHAN, Sedat ATMACA, Muhammed Enes BAYRAKDAR

A slotted ALOHA-based cognitive radio network under capture effect in Rayleigh fading channels

In this paper, a slotted ALOHA-based cognitive radio (CR) network is proposed and the throughput performance of the proposed CR network model under Rayleigh fading channels is examined. Our CR network contains two special groups of users, primary users (PUs) and CR users (CRUs), and they are considered to be sharing a timeslotted-based common communication channel. While PUs can access the channel at any time owing to their legal right, CRUs can only access the channel when it is not occupied by the PUs. In the network model developed, PUs access the channel utilizing time division multiple access as a medium access control technique, and CRUs can access the channel by exploiting slotted ALOHA as a random access scheme when the channel is idle. In the proposed network model additive white Gaussian noise and Rayleigh channels is considered for comparison reasons. Taking capture effect into account in Rayleigh fading channels, we have obtained new equations for the throughput of the proposed CR network. We have also developed, modeled, and simulated a sample networking scenario by using MATLAB with the aim of validating the analytical throughput results. Simulation results of the proposed network model precisely match with the analytical results obtained under different network load conditions. Furthermore, it is shown that the overall channel exploitation is increased by utilizing the spectrum holes without interfering with the PUs transmissions.

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[1] Akyildiz IF, Lee WY, Vuran MC, Mohanty S. NeXt generation/dynamic spectrum access/cognitive radio wireless networks: a survey. Comput Netw 2006; 50: 2127-2159.
[2] Bayrakdar ME, Atmaca S, Karahan A. A slotted ALOHA-based random access cognitive radio network with capture effect in Rayleigh fading channels. In: 2013 International Electronics, Computer and Computation Conference; 79 November 2013; Ankara, Turkey. New York, NY, USA: IEEE. pp. 72-75.
[3] Choe S. Throughput, delay, and packet capture effects in Rayleigh fading of a cognitive radio packet network. In: IEEE 2008 Wireless Days Conference; 2427 November 2008; Dubai, UAE. New York, NY, USA: IEEE. pp. 1-5.
[4] Li X, Liu H, Roy S, Zhang J, Zhang P, Ghosh C. Throughput analysis for a multi-user, multi-channel ALOHA cognitive radio system. IEEE T Wirel Commun 2012; 11: 3900-3909.
[5] Arnbak JC, Blitterswijk WV. Capacity of slotted ALOHA in Rayleigh fading channels. IEEE J Sel Area Comm 1987; 5: 261-269.
[6] Lien SY, Tseng CC, Chen KC. Carrier sensing based multiple access protocols for cognitive radio networks. In: IEEE 2008 International Communications Conference; 1923 May 2008; Beijing, China. New York, NY, USA: IEEE. pp.3208-3214.
[7] Digham FF, Alouini MS, Simon MK. On the energy detection of unknown signals over fading channels. IEEE T Commun 2007; 55: 21-24.
[8] Borgonovo F, Zorzi M. Slotted ALOHA and CDPA: a comparison of channel access performance in cellular systems. Wirel Netw 1997; 3: 43-51.
[9] Dardari D, Tralli V, Verdone R. On the capacity of slotted ALOHA with Rayleigh fading: the role played by the number of interferers. IEEE Commun Lett 2000; 4: 155-157.
[10] Dua A. Random access with multi-packet reception. IEEE T Wirel Commun 2008; 7: 2280-2288.
[11] Choe S, Park SK. Throughput of slotted ALOHA-based cognitive radio MAC. In: IEEE 2009 International Ubiquitous Information Technologies & Applications Conference; 2022 December 2009; Fukuoka, Japan. New York, NY, USA: IEEE. pp. 14.
[12] Gradshteyn IS, Ryzhik IM. Table of Integrals Series and Products. 7th ed. San Diego, CA, USA: Academic Press, 2007.
[13] Ciftci S, Torlak M. A comparison of energy detectability models for cognitive radios in fading environments. Wireless Pers Commun 2013; 68: 553-574.
[14] Ghasemi A, Sousa ES. Spectrum sensing in cognitive radio networks: the cooperation processing tradeoff. Wirel Commun Mob Comp 2007; 7: 1049-1060.
[15] Yuan J, Torlak M. Optimization of throughput and autonomous sensing in random access cognitive radio networks. In: IEEE 2011 International Wireless Communications and Mobile Computing Conference; 48 July 2011; ˙Istanbul,Turkey. New York, NY, USA: IEEE. pp. 1232- 1237.
[16] Pahlavan K, Krishnamurthy P. Networking Fundamentals: Wide, Local and Personal Area Communications.Chippenham, UK: Wiley, 2009.