What is a Wireless Sensor Network?

A wireless sensor network (WSN) is a system of one or more sensors that detect, collect and possibly respond to things like sound and vibration. These networks may be used a variety of purposes from security surveillance to medical or environmental research. Sometimes, a wireless sensor network is referred to as a smart environment. In order for the network’s data to be collected and analyzed, the wireless sensor network is often connected to a data distribution network, in which case the WSN is actually referred to as a data acquisition network.

A wireless sensor network setup can contain one or more types of sensors. These sensors may be capable of sensing any one of a variety of environmental factors. For example, there are mechanical sensors that respond to direct contact. Acoustic sensors collect auditory information while video sensors collect visual information. There are also thermal, chemical, and biosensors.

There are a number of different environments in which a wireless sensor network can be deployed. These include residential or industrial buildings, as well as outdoor environments. Mobile monitoring of vehicles, including transportation systems and ships, is also possible.

A wireless sensor network can be used for surveillance for building security or even on the battlefield. Such surveillance can report on traffic patterns and identify incursions before humans are able to see or hear them. In health care settings, miniature sensors can ease the burden of patients who previously would have been tethered to bulky, wired devices. In both cases, data could be recorded and analyzed, and alerts when certain conditions are met could be programmed.

Challenges in creating wireless sensor networks come from a variety of factors. One issue has to do with the climate conditions that can break sensors or at least inhibit their accuracy. Though the sensor's small size is advantageous in terms of portability and secrecy, it's also restricting in terms of memory and lifespan. Another common challenge has presented when too many sensors are assigned to a single data distribution network and overload the network with too much data at once.

Some WSNs only collect data in one form such as sound only. If a system were to sense temperature, humidity, and vibration, for example, a fairly rich picture of an environment can be gathered. Scientists and researchers are pushing the use of WSNs in this direction. WSNs that could be used to measure or predict earthquakes, forecast weather, or detect flooding potential are all highly sought.