Now showing 1 - 2 of 2
  • Publication
    Gibbs Sampling Aided Throughput Improvement for Next-Generation Wi-Fi
    Wireless communications, and in particular wireless local area network (WLAN) technology, has undergone a tremendous evolution in the past decades. After the release of the WLAN standard IEEE 802.11a/b in 1999, Wi-Fi technology soon became pervasive, thanks mainly to its deployment on the unlicensed ISM band. However, high traffic, especially in hotspots and areas with dense deployment of Wi-Fi access points (APs) (e.g., stations, airports, etc.) has caused major issues and a severe degradation of communications quality. The latest WLAN standards (e.g., 802.11ac, 802.11ax) have largely succeeded in improving the link quality and data rate by adopting state-of-the-art PHY layer technologies, e.g., OFDMA, MU-MIMO. However, improvement of the MAC layer in these standards is not noticeable due to restrictions such as hardware limitation and backward compatibility issues for legacy APs. As an effort to improve the MAC layer for the next-generation WLAN standard, in this paper we propose a simple algorithm with low computational complexity for channel selection in Wi-Fi networks. The main idea is to take advantage of the potential of the IEEE 802.11ax MAC to avoid major standard modifications. For this purpose, we employ the channel utilization ratio (CUR), which is measured periodically by each AP based on its channel sensing. Time-averaged CUR values are weighted based on a Gibbs sampling approach and a probability associated to each channel is updated. Finally, a channel is selected based on the aforementioned probabilities in predefined time slots. Simulation results show that the proposed approach can improve the system throughput by up to 5% and transmission delay by up to 20%.
      1151Scopus© Citations 6
  • Publication
    Satisfaction Based Channel Allocation Scheme for Self-Organization in Heterogeneous Networks
    The next-generation wireless networks are expected to become denser and more heterogeneous in order to boost the network capacity. However, densely deployed base stations (BSs) in heterogeneous networks (HetNets) can give rise to interference. On the other hand, a limited number of channels is allocated within the HetNets. Therefore, the efficient assignment of channels among BSs is considered to be an important issue. Furthermore, the density and heterogeneity of the networks motivate self-organizing resource management techniques. In this paper, we address the problem of channel allocation in HetNets, and propose a satisfaction based channel allocation algorithm. The problem is modeled as a game in satisfaction form, in which BSs act as the players with the constraint given by the loads at the BSs. The objective is to meet the data rate requirements of user equipments. In this regard, the BSs aim at seeking a satisfaction solution rather than the optimal one. In order to learn the satisfaction equilibrium, a fully distributed algorithm based on the individual utility is applied. Simulation results show that the proposed approach can increase the average BS's throughput compared to the benchmark algorithms.
      358Scopus© Citations 2