Enhancing WLAN Capacity by Strategic Placement of Tetherless Relay Points

With the proliferation of wireless local area network (WLAN) technologies, wireless Internet access via public hotspots will become a necessity in the near future. In outdoor areas where the installation of a large number of wired access points is practically or economically infeasible, mobile users located at the edge of the network communicate with the access point at a very low rate and, in turn, waste network resources. In this work, we promote the use of tetherless relay points (TRPs) to improve the throughput ot a WLAN in such environments. We first provide a high level description on how to integrate TRPs in a multirate WLAN architecture. We then propose an integer-programming optimization formulation and an iterative approach to compute the best placement of a fixed number of TRPs. Finally, we show in numerical analysis, through a case study based on relay-enabled rate adaptation and IEEE 802.11-like multirate physical model with Rayleigh fading, that, for a wide range of system parameters, significant performance gain can be achieved when TRPs are strategically installed in the network