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Cognitive Hybrid Division Duplex for Two-Tier Femtocell Networks

Soh, Yong Sheng and Quek, Tony Q. S. and Kountouris, Marios and Caire, Giuseppe (2013) Cognitive Hybrid Division Duplex for Two-Tier Femtocell Networks. IEEE Transactions on Wireless Communications, 12 (10). pp. 4852-4865. ISSN 1536-1276. doi:10.1109/TWC.2013.090313.121264.

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With the exponential increase in high rate traffic given by a new generation of wireless devices, data is expected to overwhelm cellular network capacity in the near future. Femtocell networks have been recently proposed as an efficient and cost-effective approach to provide unprecedented levels of network capacity and coverage. However, the dense and random deployment of femtocells and their uncoordinated operation raise important questions concerning interference pollution and spectrum allocation. Motivated by the flexible subchannel allocation capabilities of cognitive radio, we propose a cognitive hybrid division duplex (CHDD) that is suitable for heterogeneous networks in future mobile communication systems. Specifically, our CHDD scheme has a pair of frequency bands to perform frequency division duplex (FDD) on the macrocell, while time division duplex (TDD) is simultaneously operated in these bands by underlaid cognitive femtocells. By doing so, the proposed CHDD scheme exploits the advantages of both FDD and TDD schemes: operating in FDD at the macrocell tier controls inter-tier interference, whereas operating in TDD at the femtocell tier provides to femtocells the flexibility of adjusting uplink and downlink rates together with opportunistic access benefits. Using tools from stochastic geometry, we provide a methodology on how to design efficient switching mechanisms for cognitive TDD operation of femtocells. In particular, we derive closed-form expressions for the success probability and the area spectral efficiency of the proposed CHDD scheme when the macro tier is in downlink and uplink mode. Furthermore, we propose an open access policy as a means to improve the performance of macrocell transmissions. Our analysis and numerical results show the effectiveness of introducing cognition in femtocells so as to improve the system performance of two-tier femtocell networks.

Item Type:Article
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URLURL TypeDescription DOIArticle
Soh, Yong Sheng0000-0003-3367-1401
Additional Information:© 2013 IEEE. Manuscript received August 22, 2012; revised February 10 and May 28, 2013; accepted July 1, 2013. The associate editor coordinating the review of this paper and approving it for publication was W. Gerstacker. This paper was presented, in part, at the IEEE International Symposium on Wireless Personal Multimedia Communications, Taipei, Taiwan, Sep. 2012, and the IEEE Global Communications Conference, Anaheim, CA, Dec. 2012. This research was supported, in part, by the SRG ISTD 2012037, CAS Fellowship for Young International Scientists Grant 2011Y2GA02, SUTD-MIT International Design Centre under Grant IDSF1200106OH, and the DIGITEO-DIM Grant No. 2010-33D Project ACRON.
Funding AgencyGrant Number
SRG ISTD2012037
Chinese Academy of Sciences2011Y2GA02
SUTD-MIT International Design CentreIDSF1200106OH
Subject Keywords:Femtocell network; cognitive radio; frequency division duplex; time division duplex; stochastic geometry
Issue or Number:10
Record Number:CaltechAUTHORS:20140106-133936182
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Official Citation:Yong Sheng Soh; Quek, T.Q.S.; Kountouris, M.; Caire, G., "Cognitive Hybrid Division Duplex for Two-Tier Femtocell Networks," Wireless Communications, IEEE Transactions on , vol.12, no.10, pp.4852,4865, October 2013 doi: 10.1109/TWC.2013.090313.121264 URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:43230
Deposited By: Tony Diaz
Deposited On:09 Jan 2014 16:30
Last Modified:10 Nov 2021 16:34

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