Using Directional Antennas on Stub Wireless Mesh Networks: Impact on Throughput, Delay, and Fairness

Abstract

Wireless Mesh Networks (WMNs), which feature infrastructureless broadband network configurations, are attracting attention as an elemental technology when it comes to the extension of current WLAN infrastructures. State of the art solutions addressing WMNs usually assume the use of omnidirectional antennas.In this paper we evaluate the performance improvements obtained when using directional antennas. By using simulations, we analyze the gains in terms of throughput, delay and fairness, considering a grid network topology used to extend an infrastructure network. Simulation results show that by changing the type of antenna in use from omnidirectional to directional, the average throughput of a WMN can increase about 56% and the average network delay can be reduced by approximately 40%, without compromising fairness.

The impact of interference on the performance of a multi-path metropolitan wireless mesh network

“…The use of directional antennas can reduce interference between links of a wireless mesh network, since the antennas can beamform towards the intended receivers, which will receive only the desired transmission. The use of directional antennas has many advantages: a) each node can selectively receive signals from a desired direction and avoid interference from other directions, b) increased simultaneous communication, since more users could utilize the network simultaneously, as they will not interfere with each other or content for accessing the wireless link, c) by exploiting the gain of directional antennas, multihop transmissions can be reduced to a minimum number of hops or even to a single-hop transmission [14]. In a multiradio WMN the use of directional antennas can still create interference between the radio interfaces in each node, since the antennas are quite close to each other and their beams may overlap and thus efficient CA should be performed.…”

Predicting throughput in IEEE 802.11 based wireless networks using directional antenna

“…Omnidirectional antenna (OA) is the only antenna supported by the IEEE 802.11 standard [5] but there are many directional antenna (DA) based IEEE 802.11 networks that have been deployed [6][7][8][9][10]. The advantage of using DA [11,12] include the following: (1) a node could send signals to desired directions allowing the receiver node to avoid interference that comes from unwanted directions; this increases the signal to interference plus noise ratio (SINR); (2) the higher spatial reuse factor of DA, when compared to OA, could allow for more users to utilize a network simultaneously; (3) a source node could potentially reach its destination node in a lesser hop count in multihop scenario, due to the increased transmission range obtained from the higher gain of antenna. As such, DA may be more appealing than OA in some wireless network scenarios.…”

Power interference modeling for CSMA/CA based networks using directional antenna

“…The IEEE 802.11 standard caters for omnidirectional antenna (OA) [2] but there are many IEEE 802.11 based network deployed using directional antenna (DA) [3,4,5,6,7]. The well known motivations for using DA [8,9] include: 1) a node is able to selectively send signals to desired directions. This allows the receiver node to avoid interference that comes from unwanted directions, thereby increasing the signal to interference and noise ratio (SINR); 2) more users could utilize a network simultaneously due to the spatial reuse factor which is higher than OA; 3) in a multihop network, a source is able to reach its destination node in a lesser number of hops due to the increase of transmission range because of the higher antenna gain.…”