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A new scheme that serves to find a routing path for Wireless Sensor Networks (WSNs), with a view to facilitate an increase in the network life time is proposed in this paper. It envisages the network to be in the form of clusters and develops an algorithm for transfer of information within the nodes and to the remote Base Station (BS). The approach involves the use of Ad-hoc On Demand Distance Vector...
We present a prediction-based resource allocation algorithm (RA) for OFDMA downlink over mobile wireless channels, where prediction errors are incorporated in the problem formulation. A solution based on the empirical characterization of the prediction error is proposed. We test the proposed scheme on a realistic scenario using a practical low complexity channel predictor, suitable for implementation...
A Tactical Information Communication Network (TICN) enables communication among military entities during warfare. In a TICN, base stations (BSs) are required to move along with mobile devices in order to provide the communication wherever they are. This type of BS is referred to as Mobile Base Station (MBS). The backhaual of an MBS is composed of a wireless communication link so that the performance...
Recent works have shown that the white-space spectrum opened to cognitive radio devices is far less than what the lobbyists claimed. With fast growing number of secondary users, carefully scheduling the spectrum allocation in cognitive radio networks operating on white space becomes vital. However, the frequent ON/OFF activity of primary users (PU) and the mobility of the cognitive users make the...
This article presents UMICore, a software tool for the demonstration and visualization of various physical layer concepts as well as various channel models. The capabilities of UMICore are illustrated using UMTS LTE as exemplary physical layer with different chaYXB1-00438-A012nnel models.
In this paper, a ZigBee-based sensor network is realized and evaluations are carried out in order to clarify the fundamental performance of this sensor network. Life recording and management system is introduced as an example of ZigBee-based sensor networks, and the system is introduced into mobile WiMAX network in Azumino city in order to solve some medical problems in local cities. The following...
A common assumption in intermittently-connected (or opportunistic) mobile networks is that any contact has enough capacity to transfer the required amount of data. Although such an assumption is reasonable for analytical purposes and when contents are small, it does not hold anymore when nodes produce contents that are larger than the capacity of a contact. In such a case, nodes must slice data and...
Transmission Control Protocol (TCP) is a connection-oriented protocol for reliable end-to-end data delivery over IP networks. Many TCP variants assume that packet loss occurs due to network congestion when wired networks have very low bit error rate. TCP reacts to unreliable network conditions by slowing down the data flow with congestion window adjustment. However, the nature of frequent noise in...
Social-based forwarding algorithms provide a new perspective on the study of routing in opportunistic mobile networks, and all of these schemes assume a uniform pattern for message generating rule. However, this is unconvincing due to the heterogeneity of contact rates in human communication patterns. In this paper we propose three social-based communication pattern models and utilize them to evaluate...
In a wireless domain where a mobile user accesses heterogeneous wireless technologies with multiple interfaces, a multi-path scheduling algorithm can benefit mobile users' experience by aggregating different network bandwidth together. However, existing literature actually shows that for TCP flows, it may not be the case. To better exploit multi-path scheduling for TCP connections, this paper presents...
In the article a Photonic Integrated Antenna Unit (PIAU) capable of transmitting and receiving IEEE 802.11a/b/g signals in dual frequency band 2.4 GHz and 5 GHz has been presented. It has been experimentally shown that proposed antenna station allows to realize full-duplex wireless communication at least 10 m free-space distance between PIAU and mobile unit without any optical or electrical amplifiers.
The sensor node localization is a key technology to make application feasible and meaningful. This paper presents and analyzes a proposed localization algorithm by employing a mobile anchor node, called mobile maximum rectangle localization scheme. In the proposed scheme, a mobile anchor node moves around in sensor area and broadcasts beacon message. The sensor node uses the geometry technique to...
Mobile networks can be formed in bus, train, aircrafts, satellites with a wide variety of on-board IP-enable devices and Network Mobility (NEMO) protocols are required to support uninterrupted services to ongoing sessions. Node mobility has a direct impact on the performance evaluation of various NEMO protocols. However, most of the analysis on mobility protocols used random waypoint mobility model...
Wireless clients must associate to a specific Access Point (AP) to communicate over the Internet. Current association methods are based on maximum Received Signal Strength Index (RSSI) implying that a client associates to the strongest AP around it. This is a simple scheme that has performed well in purely distributed settings. Modern wireless networks, however, are increasingly being connected by...
This contribution compares the predicted downlink throughput coverage of a WiMAX-like system - located in a rural environment - for different operating frequencies and transmit power levels. The throughput, which is simulated using the parameters of the IEEE 802.16e-2005 standard, is based on extensive received signal power level measurements carried out with a mobile radio scanner at the frequencies...
Positive train control (PTC) provides a critical safety backup for train operations to protect against the consequences of human error. With the Rail Safety Improvement Act of 2008 mandating positive train control for most North American railroads, railroad community efforts are underway to develop an interoperable PTC communications system over a 220 MHz network. A robust, reliable, and interoperable...
In this paper, we proposed a simple yet novel multicast scheduling scheme for IEEE 802.16e wireless metropolitan area networks. Specifically, we want to solve the problem that how the base station schedules the data in a multicast superframe such that mobile stations can receive their required multicast data and the total awake time of mobile stations is minimal. We first prove that this problem is...
TCP Noordwijk has been designed and implemented to optimize short transfers (i.e. HTTP traffic) over satellite links, while assuring good performance for long transfers (e.g., FTP) as well. It was developed in the frame of an European Space Agency (ESA) project [†]. Its target scenario is a controlled communication environment adopting DVB-RCS standard between I-PEPs. A rich test campaign to both...
The IEEE 802.16e standard, also known as mobile WiMAX, has emerged as an exciting mobile wireless communication technology that promises to offer both high throughput and guaranteed quality of service (QoS). Call admission control (CAC) scheme serves as a useful tool for WiMAX, which ensures that resources are not overcommitted and thereby, all existing connections enjoy guaranteed QoS. Existing CAC...
Energy consumption is a concern with mobile de-vices nowadays. Network interfaces are among the most power hungry components in these devices. In this paper, we describe the design and implementation of a client-centric protocol for energy efficiency. Inspired by earlier work, our protocol works by exploiting the TCP flow-control mechanism to shape incoming traffic into bursts in order to utilize...
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