Product Overview 
 Provide a simple and practical based on the CDMA network communications solutions needs Kechuang communication developed DLK-D350 CDMA DTU, it embedded TCP / IP protocol stack to address the user in the use of common modules without TCP / IP protocol stack The system to be embedded in the client TCP / IP limitations, the use of reliable information on the CDMA network transparent data transfer. 
 While simplifying the interface design and external servo circuit is more suitable for harsh industrial field. User through the RS-232 (Model DLK-D350), RS-485 (Model DLK-D351), TTL (Model DLK-D352)-level interface, using simple AT + i commands, you can complete end to end reliable data communication greatly reduce the user development time and maintenance effort. 
 In addition to the product flexibility to implement a variety of equipment access, installation simple. Apply to the use of single-chip serial communications data collection and transmission system, PLC or RTU as well as industrial machine, it allows customers to existing wired serial devices need to change immediately into a wireless network communications equipment, reducing the system updates the input. 

 Industrial applications 
 Power: the city distribution network automation system, real-time monitoring and automatic compensation grid, power remote automatic meter reading 
 Highway weather station: on the highway the temperature, humidity, wind direction, wind speed and spatial resolution of the data transmission 
 Oil: Oil pipeline temperature real-time online testing, field data collection 
 Coal: Coal mine real-time online testing 
 Financial: POS machine networking 
 Communications: telecommunications room power environmental monitoring, communications, maintenance personnel line data inquiries 
 Public Security: public security, 110, traffic police vehicle monitoring and dispatching, police mobile data (identity crime files, etc.) query 
 Heat: real-time monitoring and maintenance of thermal systems 
 Industrial: Industrial remote sensing, telemetry, remote control information return 
 Weather: Weather data collection and transmission 
 Water: hydrological monitoring 
 Life: real-time data acquisition Gas regulator station automatic control, water, sewage pipes, gates and water to maintain real-time monitoring 
 Transportation: street surveillance, traffic flow information, CDMA / SMS / GPS motor vehicle monitoring and dispatching system; bank armored cars, monitoring and dispatching postal truck 

 Features 
 ◆ Built-in wireless module ZTE's MC8331A, and embedded TCP / IP protocol stack 
 ◆ similar products in the smallest (64 * 46 * 18.5), suitable for embedded integration and energy-saving mode, suitable for mobile devices 
 ◆ scalable update Firmware, better transmission quality 
 ◆ enables point to point, multipoint, and other flexible line VPDN networking, support two modes of CLIENT and SERVER 
 ◆ support for dynamic IP DNS-based protocol analysis capabilities, you can save money renting a fixed IP 
 ◆ heart model based on PING function to maintain the link flow 
 ◆ Highly Integrated CDMA and TCP / IP technology, the Internet and CDMA networks combined organic 
 ◆ support multiple TCP / IP protocol, TCP, UDP, DNS, PPP, DHCP, WAP, RAS, etc. 
 ◆ completely transparent transmission mode, data radio can completely replace the original system without any changes, system updates to minimize the input 
 ◆ support ALWAYS ONLINE (always online) mode, support for CDMA-line data transfer, support dropped reconnection; telephone wake-up; remote reset 
 ◆ Transparent mode, short connectivity, automatic timed release and link re-activated with 
 ◆ Real-time dynamic refresh, effective solution to the wireless network "false connection" phenomenon 

 Technical parameters 
 RF characteristics: 
 CDMA protocol: CDMA2000 1X Rev0 
 Frequency Range: 800M (TX 824 ~ 849MHz RX 869 ~ 894MHz) 
 Data Services: IS-707A 
 Data transmission rate: Up to 153.6kbps 
 Transmit and receive frequency interval: 45MHz 
 (450MHz, and other special frequency can be customized) 

 Electric power consumption: 
 Input voltage: DC5 ~ 25V (standard 9V power supply) 
 SIM card operating voltage: 3V/1.8V 
 Current consumption: 
 Talk mode: 120mA (average) 
 Sleep mode: 3.0mA (max) 
 Idle mode: 10.0mA (max) 

 Features: 
 Messaging content: support for digital, voice, SMS and fax 
 Module reset: The AT command or power-down reset 
 Voice coding EVRC, 13k QCELP 
 Maximum transfer rate: 14.4KBPS 

 Volume: 
 Without mounting holes and interface: 64 * 46 * 18.5mm 
 With mounting holes and interface: 78 * 66 * 18.5mm 
 Weight: 200g 

 Appearance: 
 Shell package: 
 Good electromagnetic shielding and metal shell, durable; anti-electromagnetic interference, extremely high-temperature heat capacity 
 Interface: Standard RS-232/RS-485/TTL level, DB9 Interface 
 Antenna: 50ohm/SMA/Female 

 Environment: 
 Operating temperature: -40 ℃ ~ 65 ℃ 
 Automatic shutdown:> / +70 ℃ 
 Storage temperature: -50 ℃ ~ 85 ℃ 
 Humidity: ≤ 90% 
 Magnetic compatibility: Electrostatic discharge immunity test level: 3 
 Radio frequency electromagnetic radiation: the immunity test level: 3