DESIGN ISSUES AND CLASSIFICATION OF WSNS OPERATING SYSTEMS

Wireless Sensor Networks is an emerging area of research. Wireless Sensor networks (WSNs) face lot of problems that do not arise in other types of wireless networks and computing environments. Limited computational resources, power constraints, low reliability and higher density of sensor nodes (motes) are just some basic problems that have to be considered when designing or selecting a new operating system in order to evaluate the performance of wireless sensor nodes (motes). In this paper we focused on design issues, challenges and classification of operating systems for WSNs

Variable link performance due to weather effects in a long-range, low-power LoRa sensor network

When aiming for the wider deployment of low-power sensor networks, the use of sub-GHz frequency bands shows a lot of promise in terms of robustness and minimal power consumption. Yet, when deploying such sensor networks over larger areas, the link quality can be impacted by a host of factors. Therefore, this contribution demonstrates the performance of several links in a real-world, research-oriented sensor network deployed in a (sub)urban environment. Several link characteristics are presented and analysed, exposing frequent signal deterioration and, more rarely, signal strength enhancement along certain long-distance wireless links. A connection is made between received power levels and seasonal weather changes and events. The irregular link performance presented in this paper is found to be genuinely disruptive when pushing sensor-networks to their limits in terms of range and power use. This work aims to give an indication of the severity of these effects in order to enable the design of truly reliable sensor networks

RF Energy Harvesting Wireless Communication: RF Environment, Device Hardware and Practical Issues

Radio frequency (RF) based wireless power transfer provides an attractive solution to extend the lifetime of power-constrained wireless sensor networks. Through harvesting RF energy from surrounding environments or dedicated energy sources, low-power wireless devices can be self-sustaining and environment-friendly. These features make the RF energy harvesting wireless communication (RF-EHWC) technique attractive to a wide range of applications. The objective of this article is to investigate the latest research activities on the practical RF-EHWC design. The distribution of RF energy in the real environment, the hardware design of RF-EHWC devices and the practical issues in the implementation of RF-EHWC networks are discussed. At the end of this article, we introduce several interesting applications that exploit the RF-EHWC technology to provide smart healthcare services for animals, wirelessly charge the wearable devices, and implement 5G-assisted RF-EHWC

A Design of Flood Monitoring System with Low Rate Wireless Sensor Network Coordinator with Multi-Network Using Single Processor

This article presents a design and development of a low rate wireless sensor network coordinator controller. Wireless sensor networks are cheap and comprised of a small fully autonomous processing, communication and sensing devices.This article presents a design and development of a low rate wireless sensor network coordinator controller. Wireless sensor networks are cheap and comprised of a small fully autonomous processing, communication and sensing devices. In this study develops the system for monitoring and flood warning. This research used small embedded micro controller. The system can expand into multi network and work with single processor. This design will reduce components and power assumption. The research use Propeller Chip by Parrallax Inc. This chip contains eight processors inside. All eight processors can perform tasks simultaneously or with coordination from other processors. A designed of system works together with wireless sensor networks. The first step of the experiment is creating main node and sub node in flooding area and finds transmission of data between them. Experimental results show that we can use single microcontroller work with multi-network. It can monitor result of network directly from Propeller chip by generating computer monitor signal

A Unified Wireless Sensor Network Framework

Wireless sensor networks (WSNs) have been a significant area of research over the past decade. WSN systems are used in a wide range of applications such as surveillance, environmental monitoring, target tracking, wildlife tracking, personal health monitoring, machinery monitoring, and many others. With such wide ranging applications, there is active research in nearly every facet of the field including network topologies, communication protocols, node localization, time synchronization, and sensor data processing. This movement has largely been the result of the advances in microelectronics and low-power radio systems. These advancements have enabled the design and implementation of small, powerful, low-power, wireless sensor network systems. Like any emerging technology, a standard needs to be established to allow the advances in the field to be directly leveraged rather than requiring reinvention. This paper outlines the traditional approaches to WSN system design, and in contrast, proposes the necessary components of a unified WSN framework that would support the majority of present applications as well as providing the foundation for further advancements in the field

Energy efficiency in MAC 802.15.4 for wireless sensor networks

Recent technological advances in sensors, low power integrated circuits, and wireless communications have enabled the design of low-cost, lightweight, and intelligent physiological sensor nodes. The IEEE 802.15.4 is a new wireless personal area network designed for wireless monitoring and control applications. The fast progress of research on energy efficiency in wireless sensor networks, and the need to compare with the solutions adopted in the standards motivates the need for this work. In the analysis presented, the star network configuration of 802.15.4 standard at 868 MHz is considered for a Zigbee network. In this paper, we analyze the active duration of the superframe and entered the sleep mode status inside this period. It happens when sensors do not have any data to send. The nonpersistent CSMA uses the adaptive backoff exponent. This method helps the network to be reliable under traffic changes due to save the energy consumption. The introduction of sleep state has shown incredible reduction of the power consumption in all network load changes

A Real-Time Communication Framework for Wireless Sensor Networks

Recent advances in miniaturization and low power design have led to a flurry of activity in wireless sensor networks. Sensor networks have different constraints than traditional wired networks. A wireless sensor network is a special network with large numbers of nodes equipped with embedded processors, sensors, and radios. These nodes collaborate to accomplish a common task such as environment monitoring or asset tracking. In many applications, sensor nodes will be deployed in an ad-hoc fashion without careful planning. They must organize themselves to form a multihop, wireless communication network. In sensor network environments, much research has been conducted in areas such as power consumption, self-organisation techniques, routing between the sensors, and the communication between the sensor and the sink. On the other hand, real-time communication with the Quality of Service (QoS) concept in wireless sensor networks is still an open research field. Most protocols either ignore real time or simply attempt to process as fast as possible and hope that this speed is sufficient to meet the deadline. However, the introduction of real-time communication has created additional challenges in this area. The sensor node spends most of its life routing packets from one node to another until the packet reaches the sink; therefore, the node functions as a small router most of the time. Since sensor networks deal with time-critical applications, it is often necessary for communication to meet real time constraints. However, research that deals with providing QoS guarantees for real-time traffic in sensor networks is still in its infancy.This thesis presents a real-time communication framework to provide quality of service in sensor networks environments. The proposed framework consists of four components: First, present an analytical model for implementing Priority Queuing (PQ) in a sensor node to calculate the queuing delay. The exact packet delay for corresponding classes is calculated. Further, the analytical results are validated through an extensive simulation study. Second, report on a novel analytical model based on a limited service polling discipline. The model is based on an M/D/1 queuing system (a special class of M/G/1 queuing systems), which takes into account two different classes of traffic in a sensor node. The proposed model implements two queues in a sensor node that are served in a round robin fashion. The exact queuing delay in a sensor node for corresponding classes is calculated. Then, the analytical results are validated through an extensive simulation study. Third, exhibit a novel packet delivery mechanism, namely the Multiple Level Stateless Protocol (MLSP), as a real-time protocol for sensor networks to guarantee the traffic in wireless sensor networks. MLSP improves the packet loss rate and the handling of holes in sensor network much better than its counterpart, MMSPEED. It also introduces the k-limited polling model for the first time. In addition, the whole sending packets dropped significantly compared to MMSPEED, which it leads to decrease the consumption power. Fourth, explain a new framework for moving data from the sink to the user, at a low cost and low power, using the Universal Mobile Telecommunication System (UMTS), which is standard for the Third Generation Mobile System (3G). The integration of sensor networks with the 3G mobile network infrastructure will reduce the cost of building new infrastructures and enable the large-scale deployment of sensor network

Wireless Sensor Networks: Applications

Wireless sensor networks consist of small nodes with identifying component by sensing, computation, and wireless communications infrastructure capabilities. Many path searching means routing, power management, and data dissemination protocols have been specifically designed for WSNs where energy awareness is an essential design issue. Routing protocols in WSNs might differ depending on the application and network architecture. Wireless Sensor Networks (WSNs) provide several types of applications providing comfortable and smart-economic life. A multidisciplinary research area such as wireless sensor networks, where close collaboration in some users, application domain experts, hardware designers, and software developers is needed to implement efficient systems. The easy molding, fault tolerance, high sensing fidelity, low price, and rapid deployment features of sensor networks create various new and thrilling application areas for remote sensing. In the future, this wide range of application areas will make sensor networks an essential part of our lives. However, understanding of sensor networks needs to satisfy the constraints presented by factors such as fault tolerance, scalability, cost, hardware, dynamic topology, environment, and power consumption

Early forest fire detection by vision-enabled wireless sensor networks

Wireless sensor networks constitute a powerful technology particularly suitable for environmental monitoring. With regard to wildfires, they enable low-cost fine-grained surveillance of hazardous locations like wildland-urban interfaces. This paper presents work developed during the last 4 years targeting a vision-enabled wireless sensor network node for the reliable, early on-site detection of forest fires. The tasks carried out ranged from devising a robust vision algorithm for smoke detection to the design and physical implementation of a power-efficient smart imager tailored to the characteristics of such an algorithm. By integrating this smart imager with a commercial wireless platform, we endowed the resulting system with vision capabilities and radio communication. Numerous tests were arranged in different natural scenarios in order to progressively tune all the parameters involved in the autonomous operation of this prototype node. The last test carried out, involving the prescribed burning of a 95 x 20-m shrub plot, confirmed the high degree of reliability of our approach in terms of both successful early detection and a very low false-alarm rate. Journal compilationMinisterio de Ciencia e Innovación TEC2009-11812, IPT-2011-1625-430000Office of Naval Research (USA) N000141110312Centro para el Desarrollo Tecnológico e Industrial IPC-2011100