Fig. 1
From: A traffic data collection and analysis method based on wireless sensor network
Traffic flow collecting system architecture based WSN. The data collection node uses RFM69HCW wireless module and magnetometer sensor FXOS8700CQ to build the hardware part. The magnetometer sensor identifies the vehicle flow and speed based on the vehicle's disturbance to the earth's magnetic field, and then the wireless module aggregates the data into the aggregation node. Finally, the aggregation node data is transmitted to the remote cloud server via the mobile internet