This article aims to introduce the principles and application scenarios of our company's LORA edge gateway, and teach you how to use this device to control the edge of the Internet of Things.
First of all, we need to introduce several concepts, namely our edge gateway (E870 series) concept, and LORA and LORA gateway concept, to help everyone understand what this device is for and what role it can play in the Internet of Things.
Our edge gateway has formed a complete system, including 4G version, WiFi version and LORA gateway version introduced in this article. The edge gateway is mainly for information collection and protocol conversion for the modbus protocol. This sentence needs to be understood separately. For example, there are currently 4 devices A, B, C, and D as modbus edge devices that need to report and send remote information (that is, control from the server to the device end). Then according to the current common practice, add network access plug-ins to these four devices, such as 4G-DTU or WIFI-DTU, to assist in network access. The interaction between the device and the server is assisted by DTU. However, our company's edge gateway directly integrates this step, and can directly connect all four devices A, B, C, and D together through RS485, and then configure the gateway to automatically perform information collection work for the four devices. For example, the configuration needs to collect multiple registers in four devices and export data from a total of 27 sensors. These data will be automatically collected and stored in the gateway through modbus instructions, and then the data will be converted into json protocol and uploaded to the server, because the json protocol is a more convenient and intuitive protocol for the server to process. In this way, for the server, the edge devices are no longer divided into A, B, C, and D. The server only has the concept of gateway, and does not need to pay attention to the devices mounted under the gateway, because the gateway will automatically complete the edge collection and the issuance of control instructions.
LORA and LORA gateway, among which LORA is currently a common technology in the field of civil wireless communications, it has a high receiving sensitivity, and the common (125kHz/SF12) can reach about -140 dBm. This allows it to have a longer communication distance. Generally, the current LoRA equipment has an open communication distance of more than 5km, and some high-power equipment can even reach a communication distance of tens of kilometers.
The Lora gateway is equivalent to the manager of the Lora end nodes in the entire area. For example, a factory has 100 devices, and these devices need to aggregate the device information to the Lora gateway. The management personnel only need to manage the Lora gateway. The most important thing is that it facilitates the management of the entire Lora system.
Finally, let me introduce our lora edge gateway, which is essentially a 4G edge gateway. However, as mentioned earlier, ordinary 4G edge gateways manage the modbus devices mounted below through 485 wired methods at the gateway, and directly convert the modbus interaction information between them into json protocol format and forward it to the server. The lora edge gateway changes the wired form at the bottom to the lora wireless form, which is equivalent to the server only needing to pay attention to data reading and control protocol issuance to the lora edge gateway. The edge gateway will communicate with the lora wireless network by itself and transmit this information to the edge node. This range can even cover dozens of kilometers. Yes, the devices within dozens of kilometers can be coordinated and controlled. With the gateway as the core, the control process on the server side is greatly simplified, which is very convenient for deployment.