In the rapidly developing IIoT field, 4g modem plays a crucial role. As a bridge connecting field devices and cloud platforms, 4g modem not only enables long-distance, real-time transmission of data, but also promotes the process of industrial automation and intelligence. This article will introduce the technical architecture of 4G modem and the communication protocols it supports in a simple and easy-to-understand way.

1. What is a 4G modem

The 4G modem is a data transmission device specifically designed for industrial environments. It converts serial data into IP data or transmits IP data back to the backend center through a wireless communication network. Its core function is to achieve bidirectional transparent transmission of data, enabling remote monitoring, data analysis, and fault warning for on-site equipment. 4g modem is widely used in many industries such as power, environmental protection, industrial automation, logistics, hydrology, meteorology, etc., and has become one of the core technologies for IoT applications.

2. Technical architecture of 4g modem

The technical architecture of the 4G modem mainly includes the following parts:

The hardware design of 4g modem usually uses high-performance industrial-grade processors and wireless modules to ensure stable operation in harsh industrial environments. At the same time, the hardware layer also includes serial port interfaces such as RS232/RS485, power interfaces, SIM card interfaces, etc., which are used to connect with external devices.

4g modems are usually equipped with embedded real-time operating systems to support multi-tasking, resource management, network communication, and other functions. This layer provides a stable operating environment for upper-layer applications.

The communication protocol layer is the core of 4g modem, which supports multiple communication protocols such as TCP/IP, UDP, MQTT, Modbus, LoRaWAN, etc. to adapt to different application scenarios and requirements. These protocols ensure reliable transmission, real-time performance, security, and low power consumption of data.

The application layer is the interface between 4g modem and users, providing functions such as device management, data configuration, and status monitoring. Users can remotely manage 4g modem through the application layer, achieving flexible deployment and efficient operation and maintenance of the device.

3. Communication protocols supported by 3G and 4G modems

TCP/IP protocol is the basic protocol of the Internet, and 4g modem supports TCP/IP protocol to achieve reliable data transmission. The TCP protocol is responsible for establishing reliable connections, ensuring that data is not lost, duplicated, or corrupted during transmission. It is suitable for scenarios where high quality data transmission is required, such as industrial control and remote monitoring. IP protocol is responsible for data encapsulation, routing and transmission.

Unlike TCP, UDP is a connectionless protocol with high transmission efficiency but low reliability. It is suitable for scenarios that have high real-time requirements and high tolerance for packet loss, such as online games and real-time video transmission. In the industrial Internet of Things, UDP protocol can be used for data acquisition and transmission with high real-time requirements.

MQTT is a lightweight, publish/subscribe-based communication protocol that is particularly suitable for scenarios where real-time data transmission is required and the network environment is unstable. It supports multiple QoS levels for message quality of service, allowing for the adjustment of data transmission reliability and real-time performance according to actual needs. The MQTT protocol is widely used in industrial IoT for device access, data collection, and remote monitoring.

Modbus is a widely used industrial communication protocol that enables devices to easily access industrial control systems and achieve interconnection with devices such as PLCs and sensors. Through the Modbus protocol, 4g modem can collect data from the industrial site in real time and transmit it to the remote monitoring center for centralized management and analysis. This protocol has a wide application base in the field of industrial automation.

LoRaWAN is a communication protocol for low-power wide-area networks (LPWAN), suitable for wireless communication scenarios that require long-distance, low-power wireless communication. It achieves low-cost, long-life wireless communication in a wide area by optimizing data transmission methods and reducing power consumption. In the industrial Internet of Things, the LoRaWAN protocol is often used in environmental monitoring, smart agriculture and other fields.

4. Application scenarios of 4g modem

4G modem plays an important role in many fields with its powerful data transmission capability and support for multiple communication protocols. Here are some typical application scenarios:

In the field of industrial automation, 4g modem is connected with devices such as PLC and sensors to achieve real-time data collection and transmission. Through remote monitoring and analysis, production efficiency can be improved and operation and maintenance costs can be reduced.

In the field of environmental monitoring, 4g modem uses low-power communication protocols such as LoRaWAN to achieve long-distance, low-power data transmission. It is widely used in air quality monitoring, water quality monitoring, etc., providing strong support for environmental protection.

In the field of smart agriculture, 4g modem achieves precise irrigation and fertilization of crops by collecting environmental parameters such as soil moisture and temperature. This helps improve the yield and quality of crops and reduce agricultural costs.

In the field of power monitoring, 4g modem is connected to devices such as electricity meters and transformers to achieve real-time collection and transmission of power data. Through remote monitoring and analysis, power failures can be detected in a timely manner and measures can be taken to ensure the stable operation of the power system.

As one of the core devices of the Industrial Internet of Things, the selection of its technical architecture and communication protocol is crucial for achieving efficient and reliable data transmission. By deeply understanding the technical characteristics and application scenarios of 4g modem, we can better utilize this technology to promote the process of industrial automation and intelligence. With the continuous development of technology, 4G modem will play an important role in more fields, injecting new vitality into the development of industrial Internet of Things.