Due to the high expected increase in mobile data traffic and the scarcity of licensed spectrum for cellular networks, 3GPP has started preliminary work for standardizing LTE operation in the 5 GHz unlicensed band (LTE-U). However, LTE-U would interfere with other legacy technologies operating in the unlicensed band, the most important being contention-based Wi-Fi, which would be blocked by conventional LTE, which is designed for dedicated licensed spectrum. Consequently, some coexistence-enabling mechanisms have been proposed for LTE-U, but their evaluation is still at an early stage. In this paper we present a detailed system-level study on the downlink throughput performance of legacy indoor IEEE 802.11n and LTE-U deployments coexisting in the 5 GHz band. We consider several LTE-U coexistence mechanisms (i.e. listen-before-talk and interference-aware channel selection) in indoor LTE-U femtocell and outdoor LTE-U picocell scenarios with a realistic range of network densities and real outdoor picocell locations. We also study coexistence of LTE-U networks deployed by multiple operators, and evaluate the impact of different LTE-U transmit power levels. Our results show that in general both Wi-Fi and LTE-U benefit from the large number of available channels and isolation provided by building shielding at 5 GHz. Additionally, in typical indoor coexistence scenarios, interference-aware channel selection is more efficient for both Wi-Fi and LTE-U than listen-before-talk mechanisms. For outdoor LTE-U picocells and indoor Wi-Fi deployments, the two networks are isolated from each other, but listen-before-talk can increase LTE-U user throughput when multiple outdoor LTE-U networks deployed by different cellular operators coexist.
[1]
Abhijeet Bhorkar,et al.
Performance analysis of LTE and Wi-Fi in unlicensed band using stochastic geometry
,
2014,
2014 IEEE 25th Annual International Symposium on Personal, Indoor, and Mobile Radio Communication (PIMRC).
[2]
Sayantan Choudhury,et al.
Performance Evaluation of LTE and Wi-Fi Coexistence in Unlicensed Bands
,
2013,
2013 IEEE 77th Vehicular Technology Conference (VTC Spring).
[3]
François Baccelli,et al.
A Stochastic Geometry Analysis of Dense IEEE 802.11 Networks
,
2007,
IEEE INFOCOM 2007 - 26th IEEE International Conference on Computer Communications.
[4]
Yimin Pang,et al.
On the Impact of LTE-U on Wi-Fi Performance
,
2014,
2014 IEEE 25th Annual International Symposium on Personal, Indoor, and Mobile Radio Communication (PIMRC).
[5]
I. Forkel,et al.
A multi-wall-and-floor model for indoor radio propagation
,
2001,
IEEE VTS 53rd Vehicular Technology Conference, Spring 2001. Proceedings (Cat. No.01CH37202).
[6]
PROPAGATION DATA AND PREDICTION METHODS FOR THE PLANNING OF INDOOR RADIOCOMMUNICATION SYSTEMS AND RADIO LOCAL AREA NETWORKS IN THE FREQUENCY RANGE 900 MHz TO 100 GHz
,
1997
.
[7]
Sayantan Choudhury,et al.
Enabling LTE/WiFi coexistence by LTE blank subframe allocation
,
2013,
2013 IEEE International Conference on Communications (ICC).
[8]
Mikko A. Uusitalo,et al.
System performance of LTE and IEEE 802.11 coexisting on a shared frequency band
,
2013,
2013 IEEE Wireless Communications and Networking Conference (WCNC).
[9]
Marina Petrova,et al.
Wi-Fi, but not on Steroids: Performance analysis of a Wi-Fi-like Network operating in TVWS under realistic conditions
,
2012,
2012 IEEE International Conference on Communications (ICC).
[10]
Sayantan Choudhury,et al.
Enabling the coexistence of LTE and Wi-Fi in unlicensed bands
,
2014,
IEEE Communications Magazine.
[11]
3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (e-utra); Further Advancements for E-utra Physical Layer Aspects (release 9)
,
2022
.
[12]
Andreas Achtzehn,et al.
Survey of IEEE 802.11 Wi-Fi deployments for deriving the spatial structure of opportunistic networks
,
2013,
2013 IEEE 24th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC).