One of the key areas of development of communication networks has become the concept of the Internet of things. Soon, the Internet will get connected with several billion devices. Most devices will have battery power. In this regard, one of the important characteristics of the Internet of things is the continuous operation of the device without additional maintenance and charging.
To solve problems related to energy consumption, new types of LPWANs (Low Power Wide Area Networks) were introduced, the most popular one was LoRa/LoRAWAN.
The topics which will be covered in this article are
1. LoRa modulation
LoRa modulation technology (Long Range) is a modulation method that provides a significantly greater communication range (coverage area) than other competing methods.
- This method is based on SSM (Spread Spectrum Modulation) and LFM (Linear Frequency Modulation)
- It is integrated with FEC (Forward Error Correction)
- LoRa technology increases the sensitivity of the receiver and, like other SSM (Spread Spectrum Modulation), uses the entire channel bandwidth to transmit the signal, which makes it immune to channel noise.
- LoRa technology allows demodulation of signals with levels at 19 dB, whi5 dB lower than the noise level.
- Other systems with Frequency Shift Keying (FSK) need a signal power of at least 8 to 10 dB above the noise level.
- LoRa modulation determines that Physical Layer (PHY), which can be used with various protocols and in various network architecture options, such as Mesh, Star, point to point and more.
2. What is LoRaWAN?
LoRaWAN (Long Range Wide Area Networks) is the MAC protocol for high capacity networks with a long range and low intrinsic power consumption.
- LoRa Alliance is standardized for low power global radial Networks LPWAN (Low Power Wide Area Networks ).
- The LoRaWAN protocol is optimized for low cost sensors with battery operation.
- It provides a compromise between the speed of information delivery and the operating time of devices when using battery power.
- The protocol provides a full two way communication, and the architecture ensures the overall reliability and security of the entire system.
- The LoRaWAN architecture was also designed to facilitate the discovery of mobile assets to track enterprise assets, which is one of the fastest growing applications at the Internet of Things (IoT) level.
- The LoRaWAN protocol is being developed for use in national networks of large telecom operators.
- To this end, the LoRa Alliance standardizes its LoRaWAN protocol with compatibility and interoperability with all major global carriers.
3. What is a LoRaWAN network?
Its typical architecture consists of key elements:
1. End Node
Its main functions are control and measurement. It consists of a sequence of control elements and measurement sensors.
2. Gateway LoRa
A design that receives data via a radio channel from end devices and transfers them to a transit network.
The gateway itself and its end devices form a star network topology. This type of design consists of multi channel receiving and transmitting devices that allow you to process signals arriving on several channels or several signals received from one channel.
Examples of such networks are Ethernet, WiFi, cellular networks and any other telecommunication channels.
3. Network Server
A control centre for network management. With its help, it set a schedule; it regulates speeds, analysis, processing and storage of received data takes place.
4. Application Server
A device for collecting data from end nodes and remote monitoring of their work.
4. LoRaWAN Application
- Automatic reading of readings from consumption meters of various resources (water, gas, electricity, etc.);
- Monitoring:
- smart grids
- transport and tracking of goods
- status of containers with hazardous substances in the workplace
- industrial equipment
- parking space
- weather
- smart street lighting systems
- fire and security alarms
- building automation
- automatic data collection from farmland.
5. Conclusion
LoRa only defines the physical layer of communications. On top of LoRa, you can build different networks, for example, Symphony Link and LoRaWAN. LoRaWAN is a protocol for building a network (LPWAN) on top of LoRa. It is important that the LoRa and LoRaWAN modules may not be compatible with each other. It is necessary to choose the right equipment when implementing the project.
