1. Overview

The SX1278 chip mainly uses the LoRa remote modem, which is mainly used for ultra-long-distance spread spectrum communication. It has excellent anti-jamming capability and can minimize current consumption.

The integration of high sensitivity and excellent power amplifiers has led its link budget to the industry's leading level, making it the best choice for long-distance transmission and highly demanding applications. Compared with traditional modulation technologies, LoRa modulation technology also has obvious advantages in terms of anti-blocking and selectivity. At the same time, it takes into account the advantages of communication distance,power consumption, and anti-interference.

2. Application Solution

1. The wireless data transmission module establishes a special wireless data transmission method without installing cables or digging cable trenches. It is only necessary to connect a wireless data transmission module and an antenna with an appropriate height at each terminal. In contrast, establishing a dedicated wireless data transmission method with a wireless data transmission module saves manpower and material resources, and lowers investment cost.

2. In practical applications, the communication detection system include two parts, computer(PC) and PLC. In the actual project, the computer generally consists of a wireless module as master, and the PLC consists of multiple modules as slaves. The slaves are distributed at each working point and are responsible for collecting sensors or other field data. The low-power long-distance wireless data transmission module sends the collected data to the master and receives control commands from the master. The master is responsible for sending control commands to control the work of the slaves, and at the same time accepting the data sent from the slaves, storing, analyzing, or uploading the data to the Internet.

3. In practical engineering applications, the master is generally powered by a DC power supply (not considering low power consumption). The slave is generally powered by batteries due to construction difficulty and cost (need to consider low power consumption). When the slave module is in low-power mode, the master is always active. The slave is in a low-power state when no event occurs. When an event occurs, the current event is processed. After the processing is completed, it returns to low power consumption status. By setting the master and slave to different addresses. If the address of the master is 00 00 (hexadecimal), the addresses of the slaves are 00 01, 00 02, 00 03, and so on. When the master needs to collect the data of slave 01, the format of the data to be sent is: target address + target channel + command, such as 00 01 (slave address) + channel + command. After slave 01 receives the relevant command, it returns the current data through similar commands, such as: 00 00 (master address) + channel + data. In this way, the data of the first slave is collected, that is, the second one can be continued, polling in turn, and the data can be collected. As shown below:

3. Environmental monitoring applications

•Remote control

•Home security alarm and remote keyless entry

•Remote meter reading

•Family automation telemetry

•Personal data record

•Toy control

•Sensor network

•Health monitoring

•RFID