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All living things, including humans, depend on water to survive, as do other species. Regretfully, water contamination has become a significant worldwide issue because of industrialization and irresponsible consumption. Moreover,... more
The system architecture and design are first detailed, followed by a description of the current working implementation, which is based on our DSYS25z sensing nodes. Results of a series of real experimental tests regarding connectivity,... more
This paper provides comprehensive coding and outer bound for the half-duplex multiple access channel with generalized feedback (MAC-GF). Two users communicate with one destination over a discrete memoryless channel using time division.... more
Wireless Mesh Networks (WMNs) are part of wireless technologies that are known for their flexibility and extended coverage. Wireless applications have reached their peak in applications related to various fields such as healthcare, image... more
This paper presents an experimental investigation of the performance impact of two important PHY layer design options that arise in 802.11 ad-hoc networks. In particular, throughput results are provided for multi-hop ad-hoc networks with... more
The Cache-and-Forward (CNF) protocol architecture was proposed to support efficient mobile content delivery services in the future Internet. In contrast to the TCP/IP protocol stack which is based upon the assumption of reliable end-toend... more
In this paper, we propose an Automatic Repeat reQuest (ARQ) technique for enhancing the reliability and throughput of broadband wireless Internet access applications, and provide examples of its performance. ARQ is a method for making a... more
Wireless ad hoc networks will be an important component in future communication systems. The performance of wireless ad hoc networks can be improved by link quality-aware applications. Wireless link quality is dynamic in nature,... more
It is wide spread belief that wireless mobile ad-hoc networks will be a further evolutionary step towards ubiquitous communication and computing. Due to the mobility of the network nodes, the strongly varying radio propagation conditions... more
The growth of wireless network use has greatly increased research demand. Some applications, which are contextaware, must adapt to the environment. So, information on both environment characteristics and the device's hardware are crucial.... more
The advent of wireless networks has increased the demand for research greatly. Context-aware applications must adapt to the environment in which they are inserted, and, for this, information on both device's hardware and the... more
The advent of wireless networks has increased the demand for research. Context-aware applications must adapt to the environment in which they are inserted, and, for this, information on both device's hardware and the characteristics of... more
In this letter, we propose a novel optical coding scheme for fiber link quality monitoring of a passive optical network (PON). The proposed scheme named incrementally pulse positioned coding (IPPC) is practically very attractive due to... more
In this paper we investigate both experimentally and via simulation the monitoring of fiber link quality in a PON using optical coding technology. We use a new, simple and costeffective coding scheme well adapted to the monitoring... more
Numerous analytical models have been proposed to evaluate the performance of wireless sensor networks, therefore, analytical models providing a clear understanding of the fundamental limitations of different systems, as well as a... more
Numerous analytical models have been proposed to evaluate the performance of wireless sensor networks, therefore, analytical models providing a clear understanding of the fundamental limitations of different systems, as well as a... more
OPNET Modeler accelerates network R&D and improves product quality through high-fidelity modeling and scalable simulation. It provides a virtual environment for designing protocols and devices, and for testing and demonstrating designs in... more
The accurate determination of the link quality is critical for ensuring that functionalities such as intelligent routing, load-balancing, power control and frequency selection operate efficiently. There are 4 primary metrics for capturing... more
A frequency hopping scheme (1 bit per chip) is proposed and studied in some detail for channels in the HF-band. This band is subject to interference that varies with time and frequency, due to varying transmission and channel propagation... more
Ad-hoc networks usually support best-effort traffic and occasionally some kind of Quality of Service (QoS). However, there are some applications, which generally involve cooperative control, with hard real-time traffic requirements where... more
This paper presents a software, as solution to the problem of assignment of frequency in cellular nets,denominated FA Tool, able to carry out an estimate of the number of necessary channels for station bases and to determine a plan of... more
Wireless optical communication links has the great potential to serve for an increasing demand for high bandwidth transmission capabilities. However, the widespread deployment of wireless optical communication system has been hampered by... more
High bandwidth optical wireless communication links are of prime importance, having tremendous potential to serve for the future huge data transmission requirements especially for the next generation optical networks. The inherent... more
In order to extend the coverage of wireless communication to metropolitan scale, the Worldwide Interoperability for Microwave Access (WiMAX) standard was developed and ratified as the IEEE 802.16d standard in June 2004. The standard... more
The growth of multimedia applications and wireless systems requires a new behavior of routing protocols for Wireless Mesh Networks (WMNs). It is necessary to provide not only the minimum requirements for Quality of Service (QoS), but also... more
Data compression can save energy and increase network capacity in wireless sensor networks. However, the decision of whether and when to compress data can depend upon platform hardware, topology, wireless channel conditions, and... more
Traffic engineering, as its name, is the art of manipulating traffic around so that traffic from congested links is moved onto the unused capacity on the other links. So, providing traffic engineering support in multi-hop wireless network... more
Mobile Ad Hoc Networks (MANET) are a peer-topeer communication network that can be used to transmit data using a mobile or wireless link without the support of fixed infrastructure. A literature survey highlighted that the key... more
This paper presents the design of a plug-in for the Optimized Link State Routing (OLSR) protocol with the Expected Transmission Time (ETT) metric and experiments in an indoor testbed. The ETT metric is implemented as a plug-in, keeping... more
Wireless mesh networks (WMNs) are low-cost access networks built on cooperative routing over a backbone composed of stationary wireless routers. WMNs must deal with the highly unstable wireless medium. Thus, routing metrics and protocols... more
Breadcrumb systems (BCS) have been proposed to aid firefighters inside buildings by communicating their physiological parameters to base stations outside the buildings. In this paper, we describe the design, implementation and evaluation... more
High bandwidth optical wireless communication links are of prime importance, having tremendous potential to serve for the future huge data transmission requirements especially for the next generation optical networks. The inherent... more
The study explores the intricate interplay between the quality of work life (QWL) and employees' perceptions of their impact on organizational performance. The research sheds light on the significance of both subjective and behavioral... more
With respect to the multi-hop communication pattern of wireless sensor networks, all the nodes should establish multi-hop paths towards a common data gathering point to provide a data gathering service for the underlying applications.... more
This paper examines the impact of RED on two versions of TCP-traditional TCP Reno and a newly proposed variant, TCP Veno-over 802.11b WLAN. TCP Reno was originally designed for wired networks where packet losses are primarily due to... more
WBAN technology plays a vital role in human life monitoring and maintaining health remotely without being hospitalized, particularly during pandemic situations. The miniature-sized and heterogeneous sensors involved in WBAN with limited... more
Static broadband wireless networks, due to their ease of deployment, are likely to proliferate in the near future. The major stumbling block, however, is that wireless links are prone to external interference, channel fading, inclement... more
Accurate estimation of PHY conditions would allow for better cross-layer resource management and provisioning. Unfortunately, Commercial-of-the-Shelf (COTS) typically provide very limited information. We utilize measurement studies to... more
Mobile Ad-hoc NETworks (MANETs) are characterized by bandwidth constrained links, multiple hops, varying link qualities and highly dynamic topologies. In this paper, we evaluate the performance and analyze the traffic of a mobile ad-hoc... more
This paper introduces cross-layer implementation with a multi-rate aware routing scheme and shows that SNR is an important information to use in a routing protocol. The existing routing protocol attempts to minimize the number of hops... more
Energy consumption of wireless network communication is still a big issue and a lot of research papers have proposed many solutions to increase node life time. The WMN architecture is made up of a fixed and mobile component, whereas the... more
This paper formulates a new optimization problem for direct-sequence spread spectrum systems by considering the joint transmitted power and link quality in a functional form. Link quality is measured in terms of signal interference to... more
Underutilization of the limited spectrum sparked the need for dynamic spectrum access and flexible spectrum policies. Accurate estimation of spectrum occupancy is an essential step for spectrum access in distributed networks. This paper... more
IEEE 802.11 Wireless LANs (WLANs) use rate adaptation algorithms (RAAs) to dynamically switch data rates to accommodate the fluctuating wireless channel conditions. Classic RAAs such as ARF and ONOE suffer from rate poisoning and... more
Cognitive radio technology offers an important function in the efficient utilization of the radio spectrum. Besides, it is expected that CR-enabled vehicular ad-hoc networks (CR-VANETs) enrich the communication performance of the existing... more
Cognitive radio technology offers an important function in the efficient utilization of the radio spectrum. Besides, it is expected that CR-enabled vehicular ad-hoc networks (CR-VANETs) enrich the communication performance of the existing... more
In this paper, we will present a state of the art in using multi-agent technology for wireless sensor networks where the main goal is the conception of software architecture and the network organization dedicated to optimization,... more