The third and fourth generation sensors have a time synchronization in the sub-microsecond range. Together with the mid device, sensor networks can be set up to localize of the AE sources. The mid device receives and saves the measurement data. In contrast to the configurations without localzation, the dynamic websites are not generated by the sensors but by the mid device.
The Mid Devise can be connected to five 4th generation sensors (one transmitter and four receivers) via Single Pair (SP) cables. This configuration forms an AE node. Several AE nodes that communicate with each other via WLAN can be mounted on the test object.
Advantages of the AE nodes:
Each generation 2 and 3 sensor was wirelessly connected to the mid device. This is associated with a high load on the heavily used ISM bands. In the new 4th generation, four receivers are connected to a Mid Device via SP cables. This typically reduces the amount of wireless data transmitted by a factor of 10 and increases the transmission speed by at least a factor of 4. The cables required are shorter than the distance between the transducers and easy to use because, in contrast to the Ethernet cables previously used, they only have one wire pair. The length of all cables is reduced by a factor of 10 compared to conventional AE systems with central signal processing.