Showing papers by "Mehran Abolhasan published in 2010"
TL;DR: Extensive studies simulations for DSR, AODV, LAR1, FSR and WRP in homogenous and heterogeneous networks that consist of different nodes with different resources showed that while all protocols perform reasonably well in homogeneous networking conditions, their performance suffer significantly over heterogonous networks.
60 citations
01 Dec 2010
TL;DR: The experimental results show that open80211s does not outperform existing routing protocols in practice, which indicates that more design and development effort is required for IEEE 802.11s to yield the performance that is expected for an IEEE standard protocol.
Abstract: IEEE 802.11s is an upcoming standard that defines how wireless devices can interconnect in a multi-hop configuration. While there are several protocol stacks based on the IEEE 802.11s draft standard, there has not been a formal study or comparison examining their practical performance. This paper evaluates the routing performance of open80211s in a real-world mesh testbed. The experiments benchmark open80211s against two established network layer routing protocols - OLSR and B.A.T.M.A.N.. The experimental results show that open80211s does not outperform existing routing protocols in practice. This indicates that more design and development effort is required for IEEE 802.11s to yield the performance that is expected for an IEEE standard protocol.
24 citations
18 Apr 2010
TL;DR: The results show that the proposed algorithm significantly reduces the complexity with almost the same achievable rate of the optimal allocation in a single cell case and in case of multi-cell, the proposed algorithms outperforms the conventional algorithm in terms of total network achievable data rate and overall network complexity.
Abstract: In this paper we focus on the subcarrier allocation for the uplink OFDMA based cooperative relay networks. Multiple cells were considered, each composed of a single base station (destination), multiple amplify and forward (AF) relay stations and multiple subscriber stations (sources). The effects of inter-cell interference (ICI) have been considered to optimize the subcarrier allocation with low complexity. The optimization problem aims to maximize the sum rate of all sources and at the same time maintain the fairness among them. Full channel state information (CSI) is assumed to be available at the base station. In the proposed algorithm the subcarrier allocation is performed in three steps; firstly the subcarriers are allocated to the Relay Stations (RSs) by which the received ICI on each RS is minimized. Then, the pre-allocated subcarriers are allocated to subscribers to achieve their individual rate requirements. Finally the remaining subcarriers are allocated to subscribers with the best channel condition to maximize the total sum of their data rates. The results show that the proposed algorithm significantly reduces the complexity with almost the same achievable rate of the optimal allocation in a single cell case. In case of multi-cell, the proposed algorithm outperforms the conventional algorithm in terms of total network achievable data rate and overall network complexity.
21 citations
04 Oct 2010
TL;DR: It is shown a careful configuration of the network size and power sharing between nodes can ensure optimal outage performance in the network.
Abstract: In this paper we analyze the outage probability of a cooperative multihop parallel relay network in Nakagami-m fading channels. The general closed form expression of the outage probability is derived both for integer and arbitrary Nakagami parameter m. We present numerical results on the performance of the network. It shows a careful configuration of the network size and power sharing between nodes can ensure optimal outage performance in the network.
15 citations
28 Jun 2010
TL;DR: Simulation results show DAFMAC provides a significantly higher transmission reliability in poor channel conditions than traditional ARQ techniques without modifying the device hardware.
Abstract: Opportunistic cooperation promises to enhance the user experience when streaming media over wireless devices by improving wireless network reliability at the link level. This paper presents DAFMAC, an efficient cooperative diversity partner selection algorithm for IEEE 802.11 devices. Simulation results show DAFMAC provides a significantly higher transmission reliability in poor channel conditions than traditional ARQ techniques without modifying the device hardware. Further analysis shows the low overhead of DAFMAC makes it highly competitive with other proposed cooperative retransmission mechanisms in an ad-hoc network.
12 citations
20 Sep 2010
TL;DR: Simulation results show that O TRP\_HA outperforms OTRP and AODV and it reduces overheads as a number of nodes and traffic increase, while it also further prolongs the lifetime of battery-powered single-interface nodes when compared to AODv.
Abstract: This paper presents a new routing discovery strategy for heterogeneous MANETs. Node heterogeneity is modeled in terms of: types and number of different interfaces, power, and transmission ranges. Our proposed route discovery algorithm is implemented on the top of On-demand Tree-based Routing Protocol (OTRP) and hence it is called OTRP Heterogeneity-Aware (OTRP\_HA). OTRP\_HA utilizes node heterogeneity and optimizes route discovery to reduce overheads and ensures connectivities between different types of nodes with different interfaces. Each node makes its own decision to participate in the route discovery process according to its location, local density, and available resources. Simulation results show that OTRP\_HA outperforms OTRP and AODV and it reduces overheads as a number of nodes and traffic increase, while it also further prolongs the lifetime of battery-powered single-interface nodes when compared to AODV.
9 citations