Wireless Sensor Networks
Executive Summary:
Wireless Sensor Networks are an up and coming technology that can help transform dozens of fields of research. They are exactly what you expect them to be, a network of wireless sensors that can be used to monitor conditions in any environment. When wireless sensor networks (WSNs) were originally created, they were meant to be used as a form of military surveillance. The idea was to replace land mines with a new technology that could do the same job in a more effective manner. WSNs are able to accomplish this because they can permanently detect enemy movement and then immediately alert the necessary individuals by using transceivers, unlike landmines which explode once an enemy travels over them which consequently destroys the landmine. WSNs were also much safer because there was no risk of the device blowing up, which could harm innocent bystanders. However, as WSNs became more and more accessible, people started using WSNs for civilian applications as well.
In civilian applications, WSNs eliminate both the need of expensive surveillance equipment and the cost of added employees to run the equipment. These networks are also tiny enough to be scattered around a wide area and are able to detect physical changes in the locations they are deployed in. Once the sensors detect a change, they send the data to nodes, gathering sites for the sensors, which then send the gathered information to gateway nodes. Once the gateway nodes collect the data, they wirelessly transmit the data to a computer, where a trained professional can interpret the data and transform it into useful information. While the above description may WSNs seem like a simple technology, in reality WSNs are far more complex and have a variety of uses.
Technology Description:
A WSN is composed of a series of small sensors that gather data about the physical environment. Each sensor is equipped with a radio transceiver, a small microprocessor, and a sensor (Hill). The radio transceiver enables the sensors to wirelessly transmit data to the sensor nodes, freeing the sensors of wires that would otherwise have been necessary. The microprocessor that each sensor is equipped with controls the infrastructure of the networks and allows the nodes to collect and store data. The final component are the sensors; they measure physical properties like water pressure or temperature, motion properties like velocity, contact properties like force or vibration, presence properties like distance, and identification properties (Lewis). Even though the sensors have these three components, they are still small. The picture below, for example, shows the size of a sensor compared to a penny.
WSNs are able to overcome the small size of the sensors by deploying the sensors in large quantities. WSNs deviate from here as to how they are setup. The WSNs differ in terms of robustness, bandwidth, energy efficiency, cost, and manageability. In particular, the main factor determining how a WSN is setup is driven by scalability, which refers to the ability to continue collection of information as sensory nodes increase and energy-efficiency (Zhao).
A typical WSN has the sensors use the transceivers they are equipped with to transmit the information to a sensor node. The information is then sent to a sensor node, which then sends the information to a gateway node. At the gateway node, the collected data is transmitted to a user’s computer. The picture below illustrates how sensors can be connected to sensor nodes.
Business Impact:
There are numerous advantages to using WSN. For instance, because the sensors that WSNs employ can be programmed for a variety of applications, the sensors can be used to monitor any physical condition (Lewis). This enables WSNs to provide users with various forms of data that can later be interpreted into valuable information. WSN also offer high potential profitability for businesses since the system uses technology to increase efficiency of collecting, monitoring, and processing data about the physical environment at a low cost. Finally, WSNs allow a researcher to immediately know when changes are taking place, which allows the researcher to immediately react to an event (Porter et al).
Not only do WSNs prove these benefits, but they can be used for a variety of applications as well. For example, ecologists and field biologists are using wireless sensor networks to collect environmental data in the wild (Porter et al). The WSN allows the ecologists and field biologists to survey large areas in a quick, efficient, and unobtrusive manner (Porter et al). Another way WSNs are used is in production lines (Townsend and Arms). The sensors are placed on equipment so they measure any crevices or gaps in the material to make sure that the product that is being produced conforms to production standards. These are just a few of the ways that WSNs are being used. In reality, there are hundreds and hundreds of applications of WSNs, and society is continuing to devise new and creative ways in which to use this versatile technology.
Bibliography
Hill, Jason Lester. System Architecture for Wireless Sensor Networks. 2003. June 27, 2009. <http://www.jlhlabs.com/jhill_cs/jhill_thesis.pdf>
Lewis, F. C. "Wireless Sensor Networks." Smart Environments: Technologies, Protocols, and Applications (2004): 1-18. Wireless Sensor Networks. The University of Texas at Arlington. 29 June 2009 <http://arri.uta.edu/acs/networks/WirelessSensorNetChap04.pdf>.
Porter, John, Peter Arzberger, Hans-Werner Braun, Pablo Bryant, and et al. “Wireless Sensor Networks for Ecology.” Bioscience: 55. http://proquest.umi.com.proxyau.wrlc.org/
Townsend, Chris and Steven Arms. “Wireless Sensor Networks: Principles and Applications.” Microstrain. http://microstrain.com/white/Wilson-chapter-22.pdf
Zhao, Jerry and Ramesh Govindan. "Understanding Packet Delivery Performance in Dense Wireless Sensor Networks." Conference on Embedded Network Sensory Systems (2003): 1-13. Portal. 29 June 2009 <http://portal.acm.org/citation.cfm?id=958491.958493>.
