In this work, hop-by-hop data aggregation is explained in more details, while direct wired/wireless is out the scope of this paper. The main functions of the DCU are as follows.
• Receive the monitoring data from different types of sensor nodes and measurement devices
• Classify the sensing data packets and put each type in its respective queue
• Manage three queues for analogue measurements (AM), status information (SI) and protection & control information (PCI) according to IEC 61400-25 standard
• Assembly the measurement data into sub-frames (sensor data + identification)
• Aggregate all sub-frames into one frame
• Interface with the ONU or wireless AP