Lte cat 4 modem wireless transmission module is developed on the basis of LTE cat 2 modem and supports 4G communication equipment.Compatible with 2G/3GLte cat 4 modem function, the transmission speed of Lte cat 4 modem is dozens of times faster than that of Lte cat 3 modem.You can even enjoy the freedom of the network. The TAS-L17 integrates Industrial Router, Lte cat 4 modem, VPN gateway and more.A high-performance industrial 32-bit communication processor and an industrial wireless module take an embedded real-time operating system as a software support platform,At the same time, RS232 and RS485 (or RS422) interfaces are provided, which can be directly connected to serial devices to realize the function of data transmission.
Communication between the Lte cat 4 modem and the server is done by the Lte cat 4 modem side (client).The server did not respond to the Lte cat 4 modem according to the feedback sent back, or the communication was accepted.Lte cat 4 modem and server form a network communication application system based on 4G communication and Internet technology.Compared with the Lte cat 4 modem terminal equipment, the network server terminal equipment is equipped with a more complex mobile phone application program.It can accept all communication requests sent by Lte cat 4 modem terminal equipment and check the communication status of the link anytime and anywhere.This enables the application of instant data collection and database services.
Lte cat 4 modems need to know the IP address and port number of the server before they can initiate a communication request.Once communication is established, there is no difference between the server and the Lte cat 4 modem.
The IP address of the server may be a public network IP (fixed IP) or a dynamic domain name obtained through a domain name resolution server.
The port number of the server generally matches the particular mobile application running in the server.For example, the FTP service project uses the port number TCP 21, and the Dynamic Web Server (Http) uses the port number TCP 80.That is, server-side mobile applications are suitable for pushing and receiving data based on a particular server port.
Generally, the IP address obtained by the Lte cat 4 modem terminal is the internal network IP address randomly allocated by the network operator.The mobile operator's gateway provides access to the Internet network.It is important to note that the NAT (Network Address Translation) port mapping service has a very short time limit, so if it is necessary to maintain two-way communication,Lte cat 4 modem heartbeat packets must be set to be sent at regular intervals to maintain the NAT port mapping.
Connection mode: support 4G, 2G, 3G and network
Transmission mode: transparent data transmission, configuration software protocol
Transmission protocol: support TCP, UDP, MQTT, AT command control
Data center: support dynamic domain name and fixed IP address access, multi-backup data center
Efficient: Cache function to ensure no data loss
Flexible: support real-time online, support SMS, telephone, serial data and other remote wake-up mode
Manageable: Lte cat 4 modem can be remotely configured and queried via SMS
Easy maintenance: support local firmware upgrade
Lte cat 4 modem encapsulates the PPP dial-up protocol and TCP/IP protocol stack, and has an embedded operating system.From the hardware, it can be seen as a combination of embedded PC and wireless 4G MODEM. It has the functions of 4G dial-up Internet access and TCP/IP data communication.
Lte cat 4 modem provides serial communication interfaces, including RS232, RS485 and RS422, which are commonly used serial communication modes.Lte cat 4 modem is mostly designed in the mode of "transparent transmission" of serial port data.That is to say, the Lte cat 4 modem can convert the raw data on the serial port into TCP/IP data packets for transmission.The content of the original data communication is not changed.Therefore, the Lte cat 4 modem can be connected to a variety of user equipment through serial communication without modification of the user equipment.The transmission process is greatly facilitated, and complex protocol conversion is not needed.
One of the advantages of Lte cat 4 modem devices is that they support 4G terminal devices that are always online.For this reason, a typical Lte cat 4 modem is designed to support always-on functionality.This requires the Lte cat 4 modem to be permanently on line (when there is no data communication for a long time) with the power-on automatic dialing and heartbeat package.The mobile gateway disconnects the Lte cat 4 modem from the center.Heartbeat packets are kept connected by the Lte cat 4 modem until it is disconnected from the data center.) Equipped with watchdog technology, dual protection equipment, automatic reconnection when the equipment is disconnected, automatic redialing and other functions.
Lte cat 4 modem, as a communication equipment, has a wide range of applications.In different applications, the IP address and port number of the data center and the baud rate of the serial port are different.Therefore, Lte cat 4 modems should support parameter configuration.And save the configured parameters in an internal permanent storage device (usually FLASH or EEPROM, etc.).Once powered on, it will automatically work according to the set parameters.
