Virtualization-capable multichannel WiFi system with a coordinated downlink transmission technique

This paper proposes and describes the virtualization-capable multichannel WiFi system with a coordinated downlink transmission technique which could mitigate the throughput degradation due to adjacent channel interference (ACI). The proposed system deals with the transmission for the uplink traffics and downlink traffics in different management manners; the downlink traffics from the interfere-able APs are transmitted in a synchronous manner with sending the CTS-to-self packets, while the uplink traffics are transmitted in the normal Distributed Coordination Function (DCF) manner. Simulation analyses reveal that the introduction of the coordinated downlink transmission technique could improve the maximum throughput performance by more than 130 % when an AP is interfered with the both upper and lower adjacent channels. This paper also describes the design of a prototype of the multichannel WiFi system which adopts the proposed technique.