System components in a wireless sensor network for synchronous data acquisition and wireless data transmission
A wireless sensor network (WSN) consists of distributed radio nodes to monitor physical or environmental conditions, such as temperature, sound, pressure, etc. and to transmit the data to a main location. Today such wireless sensor networks are used in many industrial applications, such as industrial process monitoring and control, machine health monitoring, and so on. Wireless sensor networks have been developed for machinery condition-based maintenance (CBM) as they offer cost savings and enable new functionalities. In wired systems, the installation of enough sensors is often limited by the cost of wiring. Previously inaccessible locations, rotating machinery, hazardous or restricted areas, and mobile assets can now be reached with wireless sensor nodes.
A wireless sensor network (WSN) consists of the following components:
- Many different sensors
- Wireless sensor nodes (also radio nodes)
- WLAN Access Point
- Evaluation software
Below, the functionality of each system component should be clearly displayed. In each case, the functionality of the system component in a wireless sensor network for wireless data transmission is explained.
Sensors capture the measured variable in a data acquisition network quantitatively. The measured variable can be captured either physically or chemically. For further processing, the sensor signal is converted into an electrical signal.
Sensor nodes serve to receive the sensor data from the sensors. For this purpose, the output signal of the sensors is transmittedto the sensor nodes. Thus, the sensor node takes the data from the sensors and sends them to a wireless access point. Therefore the sensor node has a communication module.
The WLAN access point (also wireless access point) receives the sensor data in a wireless sensor network, which are transferred to the access point from the sensor nodes wirelessly. Therefore, the WLAN access point must receive and process a variety of data from different radio nodes in order to ensure the functionality of a wireless sensor network.
For data analysis the WLAN access point is connected to an evaluation unit. This evaluation unit is usually a PC or laptop that can use a specific evaluation software, with which the sensor data is analyzed simultaneously.