A novel distributed joint beamforming algorithm for global network optimization in IEEE 802.11g-compliant WLANs

The innovative IEEE 802.11 appears like a promising standard in the future. Interference, fading and coexistence issues, that can threaten its performance, are efficiently counteracted by smart antennas. This paper proposes a novel distributed global joint beamforming algorithm especially tailored for IEEE 802.11g-compliant wireless local area networks, operating in OFDM-mode. The proposed algorithm has been designed with the aim of optimizing the overall power consumption of the communicating stations for a desired quality of service, which is an imperative optimization criterion when dealing with systems for which power consumption is crucial, such as laptops, hand-pc or mobile phones. The optimization problem is decomposed in simpler sub-problems, divided in two different types, one for transmitters and the other for receivers, iteratively solved without requiring external coordination and the knowledge of any MIMO channel matrix. Simulations show that the presented algorithm achieves rapid convergence very close to the theoretical global optimum solution.