With the rapid development of container business during recent years, how to advance the terminal operation efficiency is becoming a serious problem that needs to be settled promptly. And the most important method for improving container terminal operation efficiency is to equip the terminals with advanced technology. The terminal wireless dispatch system comes out right in this situation and has already been used in terminals of different sizes. This system consists of the following components: handset of the tally clerk; mobile terminal that fixed on the quayside container crane, front crane, and the forklift; as well as container-trailer wireless terminal and wireless base station, etc. Right now, the main container terminals are equipped with wireless handset; car-carried wireless terminal, but only a few of them have container-trailer wireless dispatch system and most of which have to choose extortionate imported equipment. So the lack of container-trailer wireless dispatch system is becoming a bottle-neck in improving terminal operation efficiency. And more and more terminals attach great importance to container-trailer wireless dispatch.

　　Whereas the users’ exigent needs and our terminal wireless implementation experience of so many years, Yantai Huadong Soft-tech Co.,Ltd researches and develops a set of container-trailer wireless dispatch system independently. This system is unique in working stability and the vast covering area (usually one base station covers a whole container terminal). The terminal product (HD-TWT6005) has gained the Radio Transmission Equipment Type Approval Certificate from state radio management committee. There follows the introduction of this system:

　　Topology of the network：

I: Introduction of container-trailer wireless dispatch system (HD-TWT6005)
　　Container-lorry wireless dispatch system (HD-TWT6005) is a tractor-mounted wireless data terminal product that developed independently by Huadong Soft-tech Co.,Ltd . This system works closely with the terminal operation system to dispatch container-trailer in real time according to the operation order. We adopt embedded developing platform in this terminal, and in terms of the part of the communications, we use narrow frequency data transmission model (230M). So it is unique in reliability, working stability, and the vast covering range. It can receive, display, and reply the orders from the dispatch end.

　　This product can be interconnected independently. Yantai Huadong Soft-tech Co.,Ltd will provide you with the interface for connecting the upper internet applications.
　　The design of the product is terse and practical. Its good quakeproof performance makes it perfect for using in port terminal. It has a high capacity/ price ratio and fits the container terminal better than other solutions.

图1：集卡终端的开机画面

Index of software performance of the terminal product

1: Screen resolution is 240*64, each screen display 4 line Chinese characters or 8 line of characters. And each line display 15 Chinese characters or 30 characters at most
2: there are totally 16 keys to represent login / exit, confirmation, cancel, function, page up, page down, 0-9 number keys respectively.

3: The communications software realizes error-checking, error-recovering and auto-retransferring, thus to ensure the reliability of the data transferring.
4、We adopt the advanced networking and collision-proof mechanism to support simultaneous working of a large number of terminals.
5: We adopt terminal automatic confirmation mechanism to ensure reliable transmission. In order to save electricity, the background light usually is not on. Only when the user presses the key or there comes messages, the background light will turn on automatically. Then 55 seconds later, if there isn’t any other operation, the light will be off.

Electric specific parameters

1: Size of the product: 190mm(length)*120mm(width)*57mm(highness); pedestal: 60mm high
2:The product can accept a comparatively wide range of input voltage: DC17V-30V
3:In order to make the product be accustomed to the unstable voltage, we add a protection function in our design in case of the abnormal voltage.
4:The allowed working environment for the product: temperature: -20°C~ 60°C, relative humidity, 5~95%and dew free environment.
5: Working frequency band:230M; 16 channels are available
6: Changeable knob is adopted in the pedestal design. As picture 5 shows:
The design of the product is terse and practical. Its good quakeproof, dustproof, and waterproof performance makes it perfect for using in the atrocious environment like port terminal.

图5：底座设计

II: Radio base station (HD-BS6005) specific parameters

III：Dispatch computer and dispatch software

　　We adopt the industrial personnel computer as the dispatch computer of this system. This computer is connected to the base station through RS-232. The dispatch information is sent to the radio base station through dispatch computer. And then the radio base station sends the information to each terminal. We fix the dispatch software on the dispatch computer. The dispatch order that sent by the TOS, will be sent to the data terminals through this dispatch software; and the returned data from terminals will be sent back to the TOS for processing.

IV：Interface software