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D120 Series Cellular IP Gateway Modem

>> Appearance


D120 Series Cellular IP Gateway Modem




More Picture and Diagram for D120 Modem >>



>> Brief


We short name Serial to GPRS Gateway as GPRS DTU IP Modem. And Serial to CDMA Gateway as CDMA DTU IP Modem.
D120 Series DTU modem enables various kinds of legacy devices with serial port to communicate over cellular network and the Internet easily and freely. It not only works as a cellular modem, but also can construct a smooth "cellular Data Tunnel" between Host and Remote side, ensuring an efficient communication for data transmission and remote device management.
With the selectable RS232/TTL/RS485/RS422 serial port, D120 Series DTU modem is an ideal solution for factory automation, environmental monitoring and remote device management etc. Meanwhile, it is supplied with simple Software interface that streamline application development process, freeing system integrators from dealing with complex communication protocols of GPRS/CDMA and the Internet. Users do not need to change the existing system, saving cost and time for field maintenance, and making it a perfect solution for data transmission.

The difference between DTU modem and normal modem

Item DTU IP Modem Normal Modem
Dial up

Support automatically dialup;

Online always; trigger to dialup, schedule to dialup
Need machine/pc back platform to dialup
Interface RS232/RS485 RS232/RS485
Bandwidth for GPRS/CDMA 20~60Kbit/s 20~60Kbit/s
Coverage Same as GSM network Same as GSM network
Transparent Data transmission Yes No
VDPN Yes Yes
Point to Point Yes Depends on network
Point to Multipoint Yes No
Center to Multipoint Yes No
Dynamite IP Address Mapping Yes No
Multi-protocol Yes No
Applications Utilities, traffic control, finance and industry supervision, for device not support dialup Mobile Internet access for PC, for device support dialup


DTU: Data Transmission Unit. Some one calls it as IP modem, or serial IP modem.
It is called as DTU modem by some users.



>>Industrial Application

  • Remote Data Monitor and Control
  • CCTV, security surveillance
  • Water, gas and oil flow metering and schedule
  • AMR (automatic meter reading)
  • Power station monitoring and control
  • Remote POS (point of sale) terminals, ATM,
  • Traffic signals monitor and control, Traffic info guidance
  • Oil field, weather forecast, environmental protection, street lamp monitoring and control
  • Early Warning of Mountain Torrent
  • Fleet management
  • Power distribution network supervision
  • Central heating system supervision
  • Weather station data transmission
  • Hydrologic data acquisition
  • Vending machine
  • Telemetry, SCADA
  • Vehicle logistics and diagnostics controlling
  • Parking meter and Taxi Monitor
  • Telecom equipment supervision (Mobile base station, microwave or optical relay station)




Related Product
D120 Datasheet





D120 Series Cellular IP Gateway Modem

>> Key Points


Built-in 2G industrial cellular module, insert SIM/UIM card to work directly;
Built-in sim card slot;
Broadband M2M communications
SIM failover/standby APN
2G failover for fixed line broadband connections
Rapid service deployment applications
Support At command
RS232/RS485 port



>> Benefits

Industrial design with intelligent software capabilities, making it a reliable GPRS solution for data collection and transmission
Plug-and-play design with easy-to-use software interface for easy integration
No need to build expensive fixed line network, saving cost substantially
Easily manage and control distributed remote devices over the air
Built-in Watch Dog
Real-time Clock (RTC)
Remote firmware upgrade over the air (OTA)
Connect to any serial device to GPRS and the Internet
Support TCP,UDP, DNS,PPP,DHCP and so on.
Reliable GPRS network connectivity, providing fast and cost-effective long-range
Always-On-Line/on Demand
Sleep mode supported
wake up Remotely (SMS or Voice call)
Support APN
Industrial design with surge protection
Local and remote configuration over the air
Multi-destination IP support


>> Basic Features

Embedded PPP, TCP/IP stack
Transparent data conversion and transmission
Supports static data service center IP address
Supports DNS and dynamic data service center IP address
Supports GPRS/EDGE customized APN or CDMA VPDN
Supports peer to peer, center to multi-point data transmission
Supports Xmodem protocol and firmware updating
Optimized EMC design
Wide range power input
Smart power management
Power on/off control
Industrial class pluggable terminal block
Standard antenna and SIM interface
Reliable, flexible, easy to use and management


>> Enhanced Features

Industrial design for different application environments
1. Industrial class components
2. Embedded RTOS


Built-in multiple communication protocols
2. E-Lins DDP, protocol, ensuring the data channel reliability
3. E-Lins AT+ protocol, satisfying the customized applications


Flexible data communication
1. Supports layer 2 and 3 data communication
2. Supports RS-232 transparent communication:
UDP/IP or TCP/IP Client/Server
3. Supports both RS-232 and Ethernet communication


Multiple operation model
1. Always online: automatic online while it powered on, automatic redial and keep-alive while the line dropped.
2. Data trigged online
3. Ring and SMS trigged online
4. Online control interface with the connected device
5.GPRS/CDMA and SMS backup and switch
6. Data loop testing


Multiple data service center communications
1. Supports up to 4 data service center communication
2. Supports main/backup data service center communication
3. Supports customized setting for each data service center


Flexible data communication
1. Supports TCP/IP Server/Client, UDP/IP, DDP, SMS, AT
2. Self-define transparent or protocol communication
3. Self-define last packet idle interval and MTU
4. Self-define customized data frame separator
5. Self-define re-connecting interval
6. Self-define online report interval
7. Self-define heart-beating data frame


Parameters configuration and remote management
1. Built-in Chinese or English configuration tool
2. PC based configuration tool
3. Remote configuration via data service center
4. Remote configuration by SMS
5. Configuration via AT+ command


Full function data service center development kits
1. Full function development package
2. Complete set of Chinese and English version demo source code (VB, VC, C#, Delphi)
3. Complete function data service center software for transparent data transmission
4. Powerful data service center testing tool


Related Product
D120 Datasheet





D120 Series Cellular IP Gateway Modem

>> Wireless


Compatible Mobile Networks


Cellular Frequency


Quad-band EGSM 850/900/1800/1900;


CDMA1x: 800/1900Mhz, option for 450Mhz;


GPRS: Downlink 85.6 kbps, Uplink 42.8 kbps;


CDMA1x: Downlink/Uplink 153.6kbps;


>> Protocol


Protocol Support: TCP/IP

>> Interface


50Ω SMA female interface, external replaceable


Serial port: DB9 (RS232, RS485, RS422, TTL option) 2400~115200bps or 300~115200bps optional
Led: Power indicator, Data indicator, Ring indicator
UIM/SIM: 1.8V/3V



>> Power


Power supply:
DC7V-25V , typical DC9V1A


Power consumption:
Peek:< 0.8A@+9VDC
Average: 30mA@+9VDC
Sleep: 3.5mA@+9VDC



>> Software


Device Management:
WEB interface (Internet Explorer v6 or Later; Mozilla Firefox v1.5 or Later, or other Java-enabled Browsers,Chome,Opera,Sarafi)


Minimum System Requirements:
Mobile Internet Access Subscription and Internet PC Adapter
Computer with:
Windows, Mac OS, Linux, or other OS
CD-ROM Drive
Network Interface Card


At command:
Support at command;


>> Physical


Operating Temperature:
Storage Temperature: -40 ~ 85°C
Working Temperature: -30 ~ 75°C


Humidity:95% Maximum (Non-condensing)


Item (L x B x H): 75mm x 50mm x 16mm
Packaging (L x B x H): 260mm x 190mm x 65mm


Item 200g (not including the antenna)
Item: 230~550g (including the antenna)
Packaging: 690g


Electronic Compatibility:
Anlistatig test: Class 3
Radio electromagnetism test: Class 3


Color: Metal Black-Gray, OEM is available



>> Others


Warranty: 1 Year default, can extend to 5 years


Package Contents:
D120 Series wireless Router
DB9 cable
Power Adapter




Related Product
D120 Datasheet





D120 Series Cellular IP Gateway Modem
M400 series router has different model versions. Here name it as follows,
Model Name Version Network Interface
D120gz 2G GPRS GPRS/GSM RS232/RS485,2400~115200bps baud rate
D120gw 2G GPRS GPRS/GSM RS232/RS485,300~115200bps baud rate
D120cz CDMA CDMA1x RS232/RS485,2400~115200bps baud rate
D120cw CDMA CDMA1x RS232/RS485,300~115200bps baud rate


Package and Accessories
D120 Series wireless Router
DB9 cable
Power Adapter
Antenna depends on features


We packed the units with free accessories; default packed depends on stock and the device’s feature requirement. If you need specify the type, please inform us when you order. For the accessories pictures, please refer to the D120 Series Modem Datasheet.



Related Product
D120 Datasheet