Wireless Sensor Networks for In-Situ Data Collection as a Part of Environmental Study and Test-Sites Infrastructure

The Wireless Sensor Networks (WSNs) are networks which are built on the base of large amount, self supplied long life nodes. The nodes are self contained devices which measure certain parameters of their surrounds, collect data, make preprocessing if needed and send the information to a base station.
The WSN is a set of hardware, firmware and software tools that allow to measure and collect certain parameters over relatively large aria. By parameters we mean any physical value convertible into electrical counterpart. For instance: air temperature, relative humidity, soil moisture, leaf wetness, wind speed and direction, the water level in a river or a tank, etc. All these values can be converted into an electrical form by means of sensors. If a sensor exists for a certain physical parameter, then it is very likely that it can be adapted to WLAN system. There are certain limitations, though the power consumption of the sensor must be low enough to allow its use with the stations, which are supplied by battery.
The electrically converted parameters are then stored in the memory of a remote measuring station. The station has its own intelligence in the form of a built-in microcontroller, which periodically performs several jobs: interrogate the sensors, store the measured data, check the radio channel, check the local battery status, and so forth. It is equipped with a radio module, which allows for realtime wireless communication with another measuring station or a base station. This means that the connection to the base station can be achieved via other remote stations, opening the possibility of building large networks.
The final goal of investigation: is remote observation of temporal and spatial distribution of physical phenomena in test site, urban and sub-urban environment.
Measuring environmental variables at appropriate temporal and spatial scales remains an important challenge in ecological research. New developments in wireless sensors and sensor networks will free ecologists from a wired world and revolutionize our ability to study ecological systems at relevant scales. In addition, sensor networks can analyze and manipulate the data they collect, thereby moving data processing from the end user to the sensor network itself. Such embedded processing will allow sensor networks to perform data analysis procedures, identify outlier data, alter sampling regimes, and ultimately control experimental infrastructure.
A wireless sensor network is only the first component in an end-to-end system that transforms raw measurements to scientifically significant data and results. This end-to-end system includes, calibration, interface with external data sources (e.g. weather data), databases, web-services interfaces, analysis, and visualization tools.