1,127 research outputs found
On Energy Efficiency and Delay Minimization in Reactive Protocols in Wireless Multi-hop Networks
In Wireless Multi-hop Networks (WMhNs), routing protocols with energy
efficient and delay reduction techniques are needed to fulfill users demands.
In this paper, we present Linear Programming models (LP_models) to assess and
enhance reactive routing protocols. To practically examine constraints of
respective LP_models over reactive protocols, we select AODV, DSR and DYMO. It
is deduced from analytical simulations of LP_models in MATLAB that quick route
repair reduces routing latency and optimizations of retransmission attempts
results efficient energy utilization. To provide quick repair, we enhance AODV
and DSR. To practically examine the efficiency of enhanced protocols in
different scenarios of WMhNs, we conduct simulations using NS- 2. From
simulation results, enhanced DSR and AODV achieve efficient output by
optimizing routing latencies and routing load in terms of retransmission
attempts
EAST: Energy Efficient Adaptive Scheme for Transmission in Wireless Sensor Networks
In this paper, we propose Energy-efficient Adaptive Scheme for Transmission
(EAST) in WSNs. EAST is IEEE 802.15.4 standard compliant. In this approach,
open-loop is used for temperature-aware link quality estimation and
compensation. Whereas, closed-loop feedback helps to divide network into three
logical regions to minimize overhead of control packets on basis of Threshold
transmitter power loss (RSSIloss) for each region and current number of
neighbor nodes that help to adapt transmit power according to link quality
changes due to temperature variation. Simulation results show that propose
scheme; EAST effectively adapts transmission power to changing link quality
with less control packets overhead and energy consumption compared to classical
approach with single region in which maximum transmitter power assigned to
compensate temperature variation
Density Controlled Divide-and-Rule Scheme for Energy Efficient Routing in Wireless Sensor Networks
Cluster based routing technique is most popular routing technique in Wireless
Sensor Networks (WSNs). Due to varying need of WSN applications efficient
energy utilization in routing protocols is still a potential area of research.
In this research work we introduced a new energy efficient cluster based
routing technique. In this technique we tried to overcome the problem of
coverage hole and energy hole. In our technique we controlled these problems by
introducing density controlled uniform distribution of nodes and fixing optimum
number of Cluster Heads (CHs) in each round. Finally we verified our technique
by experimental results of MATLAB simulations.Comment: 26th IEEE Canadian Conference on Electrical and Computer Engineering
(CCECE2013), Regina, Saskatchewan, Canada, 201
On Modeling Geometric Joint Sink Mobility with Delay-Tolerant Cluster-less Wireless Sensor Networks
Moving Sink (MS) in Wireless Sensor Networks (WSNs) has appeared as a
blessing because it collects data directly from the nodes where the concept of
relay nodes is becomes obsolete. There are, however, a few challenges to be
taken care of, like data delay tolerance and trajectory of MS which is NP-hard.
In our proposed scheme, we divide the square field in small squares. Middle
point of the partitioned area is the sojourn location of the sink, and nodes
around MS are in its transmission range, which send directly the sensed data in
a delay-tolerant fashion. Two sinks are moving simultaneously; one inside and
having four sojourn locations and other in outer trajectory having twelve
sojourn locations. Introduction of the joint mobility enhances network life and
ultimately throughput. As the MS comes under the NP-hard problem, we convert it
into a geometric problem and define it as, Geometric Sink Movement (GSM). A set
of linear programming equations has also been given in support of GSM which
prolongs network life time
Simulation Analysis of Medium Access Techniques
This paper presents comparison of Access Techniques used in Medium Access
Control (MAC) protocol for Wireless Body Area Networks (WBANs). Comparison is
performed between Time Division Multiple Access (TDMA), Frequency Division
Multiple Access (FDMA), Carrier Sense Multiple Access with Collision Avoidance
(CSMA/CA), Pure ALOHA and Slotted ALOHA (S-ALOHA). Performance metrics used for
comparison are throughput (T), delay (D) and offered load (G). The main goal
for comparison is to show which technique gives highest Throughput and lowest
Delay with increase in Load. Energy efficiency is major issue in WBAN that is
why there is need to know which technique performs best for energy conservation
and also gives minimum delay.Comment: NGWMN with 7th IEEE International Conference on Broadband and
Wireless Computing, Com- munication and Applications (BWCCA 2012), Victoria,
Canada, 201
On Link Availability Probability of Routing Protocols for Urban Scenario in VANETs
This paper presents the link availability probability. We evaluate and
compare the link availability probability for routing protocols; Ad hoc
On-demand Distance vector (AODV), Dynamic Source Routing (DSR) and Fisheye
State Routing (FSR) for different number of connections and node density. A
novel contribution of this work is enhancement in existing parameters of
routing protocols; AODV, DSR and FSR as MOD-AODV, MOD-DSR and MOD-FSR. From the
results, we observe that MOD-DSR and DSR outperform MOD-AODV, AODV, MODOLSR and
OLSR in terms of Packet Delivery Ratio (PDR), Average End-to End Delay (AE2ED),
link availability probability at the cost of high value of Normalized Routing
Overhead (NRO).Comment: IEEE Conference on Open Systems (ICOS2012)", Kuala Lumpur, Malaysia,
201
- …