Enhancing Wireless Mesh Network performance using cognitive radio with smart antennas

Abstract

In their default state, a Wireless Mesh Network (WMN) operates in the ISM band. There exist idle durations, also referred to as white spaces, in many licensed bands which could be taken advantage of by a WMN for better spectral efficiency. Use of cognitive radio in a WMN would enable Mesh Routers (MRs) that experience bad channel conditions, to shift operation to a licensed spectrum. This opportunistic sharing of white spaces results in higher spectral efficiency as well as reduced traffic volume in the ISM band. Recent research only considers using omni-directional antenna at each Mesh Client (MC). This can be inefficient, especially in case of a Cognitive WMN (CWMN) when it shifts operation to the licensed band and imposes inadmissible interference on licensed users. We study the performance improvement of a CWMN by employing smart antenna in each MC. In other words, our proposed architectural design with spatial selectivity encourages load sharing among numerous MRs in the ISM band, as well as increases throughput. Through extensive simulations, our research work analyzes the interference caused to licensed users while using omni-directional antenna. Finally, we compare scenarios where each MC in a WMN is equipped with omni-directional, directional, and smart antenna.