Lora wireless technology foundation and features
1. LoRa is a type of low-power wide area network communication (LPWAN) technology. It is an ultra-long-distance wireless transmission technology based on spread spectrum technology adopted and promoted by Semtech Company. It is more sensitive than sigfox's FSK technology, has a longer transmission distance and is more energy-saving.
2. LoRa is a physical layer (PHY) protocol that can be used in almost all network technologies.
3. The LoRa module mainly operates in the global free frequency band, with a frequency range from 137MHz to 1050MHz. The common ones are 433MHz, 868MHz, 915MHz, etc.
4. LoRa (long-range) spread spectrum technology can demodulate noise below -20dB. This ensures a highly sensitive, reliable network connection while improving network efficiency and eliminating interference.
5. LoRa no longer needs repeaters, which greatly simplifies system design and reduces total deployment costs.
6. Compared with 3G and 4G cellular networks, LoRa wireless technology is more scalable and cost-effective for embedded applications.
LoRaWAN networking
LoRaWAN is a low-power wide area network standard based on the open source MAC layer protocol launched by the LoRa Alliance. It mainly adds GateWay and LoRa Server for the MAC layer and above to facilitate remote centralized control. It is a typical star topology. In this network architecture, the LoRa gateway is a transparent transmission relay that connects the terminal device and the back-end central server. The gateway and server are connected through standard IP, and the terminal device uses a single hop to communicate with one or more gateways. There is two-way communication between all nodes and gateways, and operations such as cloud upgrades are also supported to reduce cloud communication time.
LoRa Server
1. Provide access control
Modules and gateways that comply with the LoRaWAN standard can access the LoRa network, but there is an authentication process for interconnection. Currently, the authentication is completed on the Server.
2. Data transmission and management
As the protocol processor between the gateway and the cloud, the server can realize two-way transmission of data between "gateway-server-cloud", multiple encryptions (to ensure the security of the transmission), and can perform transmission traffic statistics and transmission status monitoring.
3. Gateway management and configuration
Configure gateway frequency points, report gateway status information, etc. Multiple gateways can be connected to the same LoRaWAN Server. The Server can identify the repeated signals received, remove invalid data, and select the most effective downlink gateway. Efficiently send "responses" to module terminals.
4. Terminal node management and configuration
Server can identify different terminal nodes, respond to the nodes by allowing access/denying access, and can activate terminal nodes over the air (Over-the-Air Activation)
Server can realize terminal rate adaptation (ADR) and roaming (that is, supporting terminals to move freely within the coverage of different gateways).
5. Cloud platform communication
The server can perform data format conversion and data forwarding to meet the requirements for data sharing or transmission between different cloud platforms. Implement billing management, user management, traffic control, data storage, big data analysis, data visualization and other functions with the cloud platform.
LoRa Gateway (Gateway), also known as LoRa base station
1. Located at the core of the LoRa star network, it is an information bridge between the terminal and the server (Server), and is a multi-channel transceiver.
2. The gateway and the network server are connected through standard IP, and the terminal communicates with one or more gateways through a single hop.
3. Gateway capacity: The ability of the gateway to receive the number of data packets within a certain period of time. The number of gateway access terminals is ultimately closely related to the number of gateway channels, terminal packet sending frequency, packet sending bytes and spreading factor. Generally around 2,000.
LoRa terminal (Node)
1. LoRa terminal is an integral part of LoRa network, generally composed of LoRa modules, sensors and other devices.
2. LoRa terminals can be powered by batteries and can be positioned remotely.
3. By adding a private protocol, communication between Node and Node can be supported. Currently it is mainly used for mobile meter reading in residential areas (the meter reading instrument is also a Node, does not go through a gateway, and consumes electricity, but once a month).
Comparison of advantages and disadvantages of LoRa wireless technology
That’s it for today’s sharing. Ebyte people are committed to better supporting the development of IoT, intelligence, and automation every day, improving resource utilization, and providing more products and information. Interested friends can Log in to our official website to learn more, and the customer service ladies will answer questions online!
Other lora technical solutions recommended:
Detailed explanation of LoRa wireless transceiver communication technology
LoRa has achieved it! Low power and long-distance communication!
lora technology application solution in wireless meter reading industry
Intelligent forest fire protection system based on LoRa technology protects nature from damage!