Product Overview
The 433MHz wireless network reader WE-RWN02 can access up to 16 wireless readers, which can quickly complete the deployment of positioning base stations in an area. The communication distance between network reader (master) and wireless reader (substation) is not less than two kilometers, and the readers can work on different wireless frequency bands without affecting each other.
433MHz wireless network reader WE-RWN02 in addition to be used to access the wireless card reader, it itself can also connect a card reading antenna, as an independent card reader use. The reader detects the label distance open up to 100 meters, not only can read the ID value of the electronic label, but also can calculate the actual distance of the label by measuring the wireless signal field strength of the electronic label. A number of base stations (readers) work together, can determine the effective range of the specific location of the electronic tags, realize the personnel, the position of the goods real-time monitoring, convenient personnel, goods tracking and finding.
Application Areas
Intelligent warehouse management, logistics tracking, indoor navigation, people management and many other application areas.
ZIGBEE distance measurement formula
This product calculates the distance between the electronic tag and the antenna by measuring the wireless signal field strength of the tag, and the distance and the wireless signal strength are in an exponential curve relationship as follows:
Due to chart size limitations, only correspondences within a distance of 7 meters are shown
In the above graph, there are 3 values that we need to measure repeatedly to calibrate.
1. L0: The signal strength when the distance between the tag and the reader is 0 cm, the measured value is -8dBm.
2.L1: Signal strength when the distance between the tag and the reader is 40cm, measured value is -20dBm.
3.L2: Signal strength when the distance between the tag and the reader is 100cm, measured value is -30dBm.
4. Based on these three values, the derived formula is as follows:
For specific algorithm implementation, please refer to our DEMO software source code.