Samenvatting

Waterschap Scheldestromen has a measurement device named Multiflexmeter. It uses the LoRaWAN technology to send the measurement data to the gateway. But sometimes, the Multiflexmeter can not connect to the gateway to send data because the line of sight is blocked. So the company is seeking a design of a communication device, which could forward the data from the Multiflexmeter to the gateway.

The object of this report is to describe a LoRa multi-step communication system that has the functions of forwarding data, realizing low power consumption, and guaranteeing transmission security. The report is intended to provide a solution for the company to solve the problem of the inability to communicate between the Multiflexmeter and the gateway when the line of sight is blocked. The method used in the report is the V-model. It is a method that focuses on verification and validation. The design of the LoRa multi-step communication system is divided into three subsystems and each subsystem is also breakdown into some components. Then by integrating components into subsystems, finally, the whole LoRa multi step communication system is formed.
The LoRa multi-step communication system contains an end node, a relay node, and a gateway. The end node consisted of the same hardware (RFM95W and Atmega 328p) in the Multiflexmeter to simulate it to send data to the gateway by using the LoRaWAN protocol.
The relay node consisted of the RFM95W and Atmega328p, and it was used to forward the data from the end node to the gateway. The gateway was provided by the client, so it is unnecessary to design.
After testing, the LoRa multi-step communication system has been proved to work. The relay node can forward the data from the end node to the gateway in a signal frequency channel when the line of sight between the end node and the gateway is blocked. This relay node can be used for almost 2 years. In addition, during the transmission, the data is always encrypted to guarantee security.
There are three aspects of recommendations: Firstly, put the devices as high as possible to have a better line of sight to increase the communication distance. Secondly, design a relay gateway to forward the data in the full frequency channels. Thirdly, the working hours of the relay node can be extended by using a larger battery pack or being powered by solar panels.