A Novel Approach for Throughput Analysis of Multi-hop Multi-Rate WLANs

Nowadays the deployment of the Wireless Local Area Network (WLAN) is under the limelight of the academic community. In a multi-rate data WLAN, the data rate is a function of the distance from the access point (AP). To extend the coverage of the AP to cover a target terminal outside the AP coverage area, relay nodes are deployed between the AP and the target terminal. Therefore, for a given relationship between the throughput and the distance, and a given distance between the access point and the target receiver, there is a minimum number of nodes that provides the maximum throughput to the target receiver. It is always desirable to optimize the deployment from various aspects. These aspects are application-dependent and they range from energy conservation in sensor networks to throughput and coverage maximization in data networks. This paper presents a novel approach to determine the optimal bounds for the Medium Access Control (MAC) throughput at the target receiver in a multi-hop multi-rate wireless data network. We use the principles of linear programming and a model for the physical layer (PHY) throughput-distance relationship to determine the optimal performance bounds for the MAC throughput of a target terminal as a function of distance from the AP and the number of hops. Additionally, we determine the physical locations for the relays to reach the optimal MAC throughput for a target terminal located at a specific distance from the AP.