Search results for "Wi-Fi array"

Mobile Wireless Interfaces: In Search for the Limits

2002

With the proliferation of 2G and 3G Telecom and other wireless networks hundred of millions of users will be able to access wireless services with their terminals in only a few years. In this paper we discuss the possibilities and limitations of existing and emerging mobile technologies and methodologies for porting information and functionality from traditional PCs to mobile devices and vice versa. We argue that in order to be able to properly port things between devices an equivalence concept for user interfaces is required.

Fuzzy topology discovery protocol for SDN-based wireless sensor networks

2017

Abstract The growing trend in pervasive systems forces traditional wireless sensor networks to deal with new challenges, such as dynamic application requirements and heterogeneous networks. One of the latest paradigms in this area is software defined wireless sensor network. According to the paradigm, the networks take care of managing topological information and forwarding decisions using a bipartite architecture in which a control plane decides the forwarding policies and the data plane (i.e. ordinary sensor nodes) executes them. Unfortunately, in highly dynamic networks, this approach generates an overhead of control packet exchange between the ordinary nodes and the control plane, that …

Distributed and mobile systems based on wireless networks: definition of a generic control architecture

2005

The tendency toward the use of distributed systems is due to these systems have demonstrated to be a good option for the industrial control systems implementation, because of their flexibility and power, which can be increased with the application of artificial intelligence techniques. In this line, our research group has developed several distributed systems applied to chemical analysis and industrial automation. For these implementations the CAN network was used. Nowadays there is a market for technical tasks like distributed control, monitoring or data acquisition where there is a need for wireless connectivity. Thus, in this paper we want to discuss possibilities and necessary developme…

Enabling ubiquitous wireless sensor networks: A new fault tolerant RF architecture with perpetual electrical power based on 802.15.4 and RFID

2007

The wireless communications field is in continuous growth and revolution. The current trend toward the use of distributed wireless systems is due to these systems have demonstrated to be a good option due to its flexibility and power. In this line, nowadays there is an enormous demand of wireless connectivity for any industrial control applications, included critical systems. In this paper, we want to discuss possibilities and necessary developments to set up wireless communication for industrial applications in general and critical systems in particular. Furthermore, an abstract definition of a layered architecture for the development of intelligent and distributed control systems based on…

QoS Mechanisms for IEEE 802.11 Wireless LANs

2004

Currently the Internet provides users with access to information across the world using IP technology. Until now most access points to the Internet have been fixed stations at given locations, but with increasing sales of mobile devices, mobility has become a major trend. Therefore, the Internet is becoming more and more heterogeneous due to the recent explosion of wireless networks. The IEEE 802.11 wireless LAN (WLAN) is the most widely used WLAN standard nowadays. Currently the IEEE 802.11 standard specifies an over-the-air interface between wireless devices. However, QoS services over this technology are still being defined aiming to provide support to multiple applications. Thus, a larg…

A Note on the Local Minimum Problem in Wireless Sensor Networks

2013

The Local Minimum Problem occurs in geographic routing scenarios. In this paper two solutions to this problem for certain network topologies are proposed. By using the notion of virtual coordinates a theoretical and a practical constructions are presented. A distributed algorithm for the practical approach is proposed.

On Applications of Wireless Sensor Networks

2009

Wireless Sensor Networks (WSN) are ad-hoc networks in which small independent sensor nodes have limited energy, computational resources and wireless communication capabilities. Recently, both academia and industry have shown great interest in the area of Wireless Sensor Networks. This paper focuses on the practical applications in commerce and feasible future employment of WSNs. Continued advances of wireless communication technologies have led to the following fields of applications: habitat and environmental monitoring, security of buildings and property, oil and gas installations, mines and tunnels, emergency medical care, military applications. In the near future WSNs will certainly ent…

Coded addresses in multi-hop wireless sensor networks

2014

A CAPWAP Architecture for Automatic Frequency Planning in WLAN

2007

Recently, the impressive success of the IEEE 802.11 WLAN technology has dramatically changed the role of the wireless connectivity provisioning. Born as a wireless extension of small office or home networks, todays the WLANs are getting more and more popular as a large, even metropolitan, area networks. The deployment of large-scale WLANs has some critical issues, because of the lack of coordinated management functionalities among the network nodes. In this paper we briefly describe the CAPWAP architectural solution, for centralizing some control and maintenance functionalities in large scale WLAN, by guaranteeing the interoperability between network nodes provided by different vendors. We …

A Logical Framework for Augmented Simulations of Wireless Sensor Networks

2006

This paper describes a framework for practical and efficient monitoring of a wireless sensor network. The architecture proposed exploits the dynamic reasoning capabilities of the situation calculus in order to assess the sensor network behavior before actually deploying all the nodes. Designing a wireless sensor network for a specific application typically involves a preliminary phase of simulations that rely on specialized software, whose behavior does not necessarily reproduce what will be experienced by an actual network. On the other hand, delaying the test phase until deployment may not be advisable due to unreasonable costs. This paper suggests the adoption of a hybrid approach that i…