Serial to CDMA GatewayCDMA DTU Modem is an industrial modem with RS232/RS485/TTL interface for wireless M2M solutions. We call it DTU in China, and actually it's a CDMA RS232/RS485 to Cellular Gateway IP modem. Short name for IP modem, or RS232 Serial CDMA Gateway.


The CDMA DTU Modem is a CDMA cellular modem with transparent transmission feature. Working under GSM/GPRS networks.


The GPRS DTU modem is a CDMA modem rs232 or rs485 port. Also there is TTL interface embedded version.


2.75G mobile communication technology (CDMA1x) has become widely used of industrials and utilities in recent years and many customers are seeking reliable, flexible and cost-effective data channel to build their information system. Many applications such as ATM, POS, SCADA and surveillance system will require data channels covered all country; this brings a bright future for CDMA data networks applications.Requirements towards information system are varied because of different features of numerous industrial applications. Mobile telecom service providers are required to provide industrial application solutions not only meeting common specifications and also individual special ones.


D130 CDMA DTU cellular modem is a data termination unit based on GPRS or CDMA mobile network. It provides data communication network for industrial applications. With the reliable, flexible and cost-effectiveness features, it can be utilized at many areas to provide the M2M communication channels.
D130 CDMA DTU cellular modem provides RS-232/RS-485/RS-422/TTL interface. Embedded with PPP, TCP/IP and DDPTM protocol, it converts the user data into CDMA 1x network and transmits the data into the customer’s data service center. With the professional designing, the D130 CDMA cellular DTU modem provides the plug and play, easy to use and maintenance features.


D120 Series CDMA M2M modem(data transmission unit) combined CDMA and Internet technology .It run IP procotol over CDMA networks . A non-interneted device can establish a internet connection by the PnP DTU. Internet-enable any RS232 device over CDMA cellular networks reliable solution for IP-based communication and CDMA network services low-cost, non-PC devices running M2M applications mediate the connection between a serial port device and the Internet eliminate the need for Internet programming and minimizes changes to the host application a real plug-and-play device.


Industrial Application - Wireless M2M

  • 1) Remote Data Monitor and Control;

  • 2) CCTV, security surveillance;
  • 3) Water, gas and oil flow metering and schedule;
  • 4) AMR (automatic meter reading);
  • 5) Power station monitoring and control;
  • 6) Remote POS (point of sale) terminals, ATM,
  • 7) Traffic signals monitor and control, Traffic info guidance;
  • 8) Oil field, weather forecast, environmental protection, street lamp monitoring and control
  • 9) Early Warning of Mountain Torrent;
  • 10) Fleet management;
  • 11) Power distribution network supervision;
  • 12) Central heating system supervision;
  • 13) Weather station data transmission;
  • 14) Hydrologic data acquisition;
  • 15) Vending machine;
  • 16) Telemetry, SCADA;
  • 17) Vehicle logistics and diagnostics controlling;
  • 18) Parking meter and Taxi Monitor;
19) Telecom equipment supervision (Mobile base station, microwave or optical relay station)


Main Feature of CDMA Serial to Cellular Gateway

  • 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/3G 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 Feature of CDMA Serial to Cellular Gateway


Industrial design for different application environments:

1. Industrial class components
2. Embedded RTOS


Built-in multiple communication protocols:



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


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

Download - CDMA M2M Modem

D120c Serial to CDMA Gateway UserManual


The difference between DTU IP Modem and normal Modem: Click to download


Catalog - Router Modem AP


Industrial Class Series


SOHO Class Series

Appearance - CDMA M2M Modem
CDMA M2M Modem
TIA/EIA-95B, CDMA2000 1X
Band class 0:800/1900MHz or 450Mhz
Data Transmission, always online, auto redail up, remote wakeup or reboot via phone
DC 5V-25V
Support Firmware update for better quality
Dimension: 75*50/72*16mm
Weight: 200g

Dimension: 72*46*14.5mm
weight: 100g
Steel shell: good electromagnetic shield and , heat radiate performance
Electromagnetic Compatible
Electrostatic Discharge (ESD): 3 class
Radiated, radio-frequency, electromagnetic field immunity test: 3 class
Work: -30°C ~ 75°C
Storage: -40°C to 85°C
Humidity: 95% (non-condensing)
Product Module Network Power Level Interface Order No.
D120cZ311 ZTE MG815+ 800MHz DC 5V~25V RS-232 DB9  
D120cZ811 ZTE MG415+ 450MHz DC 5V~25V RS-232 DB9  
D230Z311 ZTE MG815+ 800MHz DC 5V~25V RS-232 20PIN  
D230Z811 ZTE MG415+ 450MHz DC 5V~25V RS-232 20PIN