Spectrum sharing between IEEE 802.16 and IEEE 802.11 based wireless networks

Abstract

Due to the high scarcity and high costs of radio spectrum, more and more radio services are occupying unlicensed bands for their operation. Due to this, there is a high risk of destructive interference which degrades the performance and fails to support Quality of Service (QoS) for systems operating in these bands. IEEE 802.11 based wireless networks are already operating in unlicensed band. A new competitor for unlicensed bands is the IEEE 802.16 based wireless metropolitan area network. Therefore, spectrum sharing between coexisting competing wireless systems like 802.11 and 802.16 is an upcoming challenge. To understand the characteristics of interference in such a heterogeneous scenario, an analysis of possible interference is presented and the performance of the legacy systems is evaluated. Then a spectrum sharing concept is proposed which can generally be applied to both systems. In this paper, the proposed concept is adapted for coexisting 802.16 and 802.11e based systems, which is an extention of 802.11. In this case, the 802.11e Hybrid Coordination Function (HCF) Controlled Channel Access (HCCA) is extended to provide a protocol for airtime sharing. Simulation results are presented showing that the proposed algorithm provides excellent improvement of system performance in the context of capacity and channel utilization compared to the case without applying any spectrum sharing method.