Many incompatible wireless protocols proliferate in unlicensed bands, creating complex coexistence and connectivity problems. If the trend continues, such problems will continue to exist in future unlicensed bands. We take a different approach to spectrum sharing. Instead of proposing a distinct medium-access control (MAC) protocol for each type of application, we propose a family of parameterized MAC protocols called WiFlex, which can be tailored to different application needs, ranging from wireless sensors to media centers. However, these protocols allow communication and spectrum-sharing coordination among different types of devices. We envision this family to be based on a multichannel physical layer. The contributions of this paper include a novel asynchronous split phase (ASP) protocol with dynamic priority support, even in multiple-collision-domain environments. When links are bidirectional, WiFlex resolves the multichannel hidden-node problem, achieving collision-free data exchange in a multihop environment. ASP provides a mechanism for prioritization and fairness. The performance of the protocol is evaluated through analysis and simulation. The coexistence of heterogeneous devices and the support for different applications with high performance are demonstrated.
Bibliographical noteFunding Information:
Manuscript received July 17, 2009; revised October 26, 2009, March 26, 2010, and April 27, 2010; accepted May 21, 2010. Date of publication June 14, 2010; date of current version September 17, 2010. This work was supported in part by the National Science Foundation under Grant CNS-0435478 and in part by Broma Information Technology Research Center (ITRC) of the Ministry of Knowledge Economy, Korea, under Grant NIPA-2010-(C1090-1011-0011). An earlier version of this paper was published at the 2008 IEEE Wireless Communications and Networking Conference. The review of this paper was coordinated by Prof. V. W. S. Wong.
All Science Journal Classification (ASJC) codes
- Automotive Engineering
- Aerospace Engineering
- Electrical and Electronic Engineering
- Applied Mathematics