User Cooperation for Traffic Offloading in Remote Hotspots

Serving mobile stations in a remote hotspot with ultra high user density in the vicinity of a densely populated area is a challenging problem in terms of user separation and necessary infrastructure. Such a scenario arises e.g. at music festivals, sport events or in emergency situations. In this context, we propose to serve the mobile stations in such a remote hotspot by user cooperation combined with traffic offloading. That is, the mobile stations shall form a virtual MIMO array and jointly access the WLAN access points in the surrounding. Based on numerical simulations with realistic parameters, the performance of the user cooperation scheme is evaluated and its interdependency with the local users assigned to the WLAN access points is investigated. It is thereby shown, that the performance of the local users strongly suffers from the hotspot traffic. Hence, two different schemes trading off the performance of the local users versus the performance of the mobile stations in the hotspot are proposed and evaluated.