5,917 research outputs found
The impact of mobility models on the performance of mobile Ad Hoc network routing protocol
A mobility model represents nodes distribution and movement over the network. Several research works have shown that a selection of mobility model can affect the outcome of routing performance simulation in Mobile Ad Hoc Networks. Thus, a routing protocol may only be effective in a particular mobility model or scenario but performs inferiorly in another. As a result, analyses of routing protocol performance are often based on inadequate information leading to inaccurate argument and conclusion. In this paper, three different mobility models have been selected, where each of them is highly distinctive in terms of nodes movement behavior. In addition, a new measurement technique called probability of route connectivity is introduced. The technique is used to quantify the success rate of route established by a routing protocol. Extensive simulation runs are done and results are compared between each mobility model
Continuum percolation of wireless ad hoc communication networks
Wireless multi-hop ad hoc communication networks represent an
infrastructure-less and self-organized generalization of todays wireless
cellular networks. Connectivity within such a network is an important issue.
Continuum percolation and technology-driven mutations thereof allow to address
this issue in the static limit and to construct a simple distributed protocol,
guaranteeing strong connectivity almost surely and independently of various
typical uncorrelated and correlated random spatial patterns of participating ad
hoc nodes.Comment: 30 pages, to be published in Physica
A Self-Organization Framework for Wireless Ad Hoc Networks as Small Worlds
Motivated by the benefits of small world networks, we propose a
self-organization framework for wireless ad hoc networks. We investigate the
use of directional beamforming for creating long-range short cuts between
nodes. Using simulation results for randomized beamforming as a guideline, we
identify crucial design issues for algorithm design. Our results show that,
while significant path length reduction is achievable, this is accompanied by
the problem of asymmetric paths between nodes. Subsequently, we propose a
distributed algorithm for small world creation that achieves path length
reduction while maintaining connectivity. We define a new centrality measure
that estimates the structural importance of nodes based on traffic flow in the
network, which is used to identify the optimum nodes for beamforming. We show,
using simulations, that this leads to significant reduction in path length
while maintaining connectivity.Comment: Submitted to IEEE Transactions on Vehicular Technolog
Faster Information Propagation on Highways: a Virtual MIMO Approach
In vehicular communications, traffic-related information should be spread
over the network as quickly as possible to maintain a safe and reliable
transportation system. This motivates us to develop more efficient information
propagation schemes. In this paper, we propose a novel cluster-based
cooperative information forwarding scheme, in which the vehicles
opportunistically form virtual antenna arrays to boost one-hop transmission
range and therefore accelerate information propagation along the highway. Both
closed-form results of the transmission range gain and the improved Information
Propagation Speed (IPS) are derived and verified by simulations. It is observed
that the proposed scheme demonstrates the most significant IPS gain in moderate
traffic scenarios, whereas too dense or too sparse vehicle density results in
less gain. Moreover, it is also shown that increased mobility offers more
contact opportunities and thus facilitates information propagation.Comment: IEEE 2014 Global Telecommunications Conference (GLOBECOM 2014) -
Communication Theory Symposiu
Impact of network structure on the capacity of wireless multihop ad hoc communication
As a representative of a complex technological system, so-called wireless
multihop ad hoc communication networks are discussed. They represent an
infrastructure-less generalization of todays wireless cellular phone networks.
Lacking a central control authority, the ad hoc nodes have to coordinate
themselves such that the overall network performs in an optimal way. A
performance indicator is the end-to-end throughput capacity.
Various models, generating differing ad hoc network structure via differing
transmission power assignments, are constructed and characterized. They serve
as input for a generic data traffic simulation as well as some semi-analytic
estimations. The latter reveal that due to the most-critical-node effect the
end-to-end throughput capacity sensitively depends on the underlying network
structure, resulting in differing scaling laws with respect to network size.Comment: 30 pages, to be published in Physica
An Energy Balanced Dynamic Topology Control Algorithm for Improved Network Lifetime
In wireless sensor networks, a few sensor nodes end up being vulnerable to
potentially rapid depletion of the battery reserves due to either their central
location or just the traffic patterns generated by the application. Traditional
energy management strategies, such as those which use topology control
algorithms, reduce the energy consumed at each node to the minimum necessary.
In this paper, we use a different approach that balances the energy consumption
at each of the nodes, thus increasing the functional lifetime of the network.
We propose a new distributed dynamic topology control algorithm called Energy
Balanced Topology Control (EBTC) which considers the actual energy consumed for
each transmission and reception to achieve the goal of an increased functional
lifetime. We analyze the algorithm's computational and communication complexity
and show that it is equivalent or lower in complexity to other dynamic topology
control algorithms. Using an empirical model of energy consumption, we show
that the EBTC algorithm increases the lifetime of a wireless sensor network by
over 40% compared to the best of previously known algorithms
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