Resource Allocation for QF VMIMO Receive Cooperation in Urban Traffic Hotspots

摘要

User cooperation enabled traffic offloading has been shown to be a promising concept to serve a large number of mobile stations in the uplink of an urban traffic hotspot scenario. Multiple mobile stations form a virtual antenna array and jointly access the nearby WLAN access points, achieving large gains compared to non-cooperating schemes. In this paper we consider the corresponding downlink, where the non-cooperating WLAN access points individually transmit their signals to the mobile stations in the hotspot. In order to decode these signals, each mobile station then quantizes its received signal and broadcasts it to the other cooperating mobile stations. The channel access times allocated to the cooperating mobile stations in the broadcasting phase thereby strongly impact the quantization rates and eventually the system performance. Hence, these resources have to be assigned carefully, leading to a non-convex optimization problem. In this context, we propose an efficient resource allocation scheme which yields promising results at low computational complexity. Applying this scheme we then evaluate the downlink of user cooperation enable traffic offloading in an urban traffic hotspot scenario.