Wireless Mesh Networks (WMNs) have attracted a great deal of interest in recent years as a cost-effective method to provide a wireless network infrastructure. To accommodate various types of application traffic in WMNs, improvement of network capacity is one of the most critical issues. The efficiency of wireless network resource utilization decreases due to radio interference when multiple transmissions occur simultaneously in an interference region. To resolve this problem, we focus on the transmission power control of mesh nodes. We expect to improve spatial reuse by applying power control because this decreases radio interference between wireless links. In this paper, we propose power control methods of mesh nodes for improving spatial reuse in TDMA-based wireless mesh networks. We first propose two types of power control methods, which employ a simple threshold-based mechanism. Furthermore, we develop an additional method that suppresses the unnecessary increase in path length associated with limiting the increase in the hop count to the nearby mesh nodes. Numerical evaluation results reveal that the proposed method decreases the frame length by up to 27% with non sensitive parameter setting. 1. Introduction Wireless Mesh Networks (WMNs) have attracted a great deal of interest in recent years as a cost-effective method by which to provide a wireless network infrastructure [1, 2]. A WMN generally consists of three types of network nodes, namely, mesh nodes, gateway nodes, and stations, as illustrated in Figure 1. A collection of mesh nodes form the backbone network by constructing wireless links between mesh nodes within the radio transmission range. Unlike the traditional Wireless Local Area Network (WLAN), only a portion of the mesh nodes need be connected to the wired network. The mesh nodes that are connected to the wired network are called gateway nodes and other mesh nodes connect to the wired network by multihop connections through gateway nodes. The stations connect to one of the mesh nodes and communicate with other stations or access a wired network such as the Internet via the gateway node through the backbone network of mesh nodes. Wireless connection realizes the cost-effective deployment of access networks, as compared to the use of a wired connection, and provides good extensibility without geographical limitations. Figure 1: Wireless mesh network. One of the major problems in constructing a WMN is radio interference caused by simultaneous transmissions in the interference region [3]. In the WMN, since all mesh nodes generally share
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