A Cross-Layer Resource Allocation Algorithm for WLANs

Tailored for the wireless local area networks (WLANs), the present paper proposed a cross-layer resource allocation algorithm. We adopted space-time block code (STBC) at the physical (PHY) layer and request-to-send/clear-to-send (RTS/CTS) based on carrier sense multiple access protocol with collision avoidance (CSMA/CA) at the medium access control (MAC) layer. Proposed algorithm consisted of three stages. Firstly, the bandwidth for the selected users according to the data packet length was allocated. Then, subcarriers based on the bandwidth and equivalent channel gain were allocated to users. Finally, water filling algorithm was performed to allocate power for each user. The simulation results show that proposed algorithm outperforms the conventional algorithm where cross layer design is not used and proposed algorithm has very low computational complexity which can meet the requirement of real-time communication.