无人船与岸上通信是由GPRS通信模块来完成的，在设计中，单独设计了GP

The unmanned ship and the shore communication are completed by the GPRS communication module. In the design, the GPRS communication module is designed separately and connected to the main control center of the unmanned ship's lower computer through the serial port. The GPRS communication subsystem uses the SIM900A industrial-grade module produced by SIMCOM. It mainly supports functions such as short and short message transmission and reception, data flow Internet access, voice call and fax. It mainly has two working frequency bands, and its embedded TCP / IP communication protocol supports TCP / UDP communication and FTP / HTTP services can also be controlled by AT commands. The power supply mode is DC power supply. The voltage value is generally between 5V and 24V. In the case of 12V power supply, the current value is about 45 mA in the case of normal GPRS communication, and the sleep current is about 12 mA, but the data is just At the beginning of transmission, the maximum instantaneous current is up to 90 mA, and the corresponding instantaneous current of SIM900A is 2A / 4V. When the conversion efficiency is 80%, the instantaneous current at the power input must be not less than 833 mA / 12 V When designing the circuit, pay special attention to the design of the power module circuit. The output used in this design is a 12V DC switching power supply.

无人船与岸上通信是由GPRS通信模块来完成的，在设计中，单独设计了GPRS通信模块，通过串口与无人船下位机主控制中心进行相连。GPRS通信子系统采用SIMCOM公司生产的工业级模块SIM900A，主要支持短、信收发、数据流量上网、语音通话和传真等功能，主要有两个工作频段，其内嵌了TCP/IP通信协议，支持TCP/UDP通信和FTP/HTTP服务，同时也可以用AT命令进行控制。供电方式为直流供电，电压值一般在5V到24V之间，在12V供电的情况下，GPRS正常通信的情况下电流值为45毫安左右，睡眠状态电流约为12毫安，但是在数据刚开始传输的时候，最大瞬间电流高达90毫安，对应SIM900A的瞬间电流达2A/4V，在转换效率为80%的情况下，电源输入端的瞬间电流必须不低于833毫安/12伏特，所以在设计电路时，尤其要注意电源模块电路的设计，本设计中采用的是输出为12V直流开关电源供电。

The communication between the unmanned ship and the shore is completed by GPRS communication module. In the design, GPRS communication module is designed separately, which is connected with the main control center of the unmanned ship's lower computer through the serial port. GPRS communication subsystem adopts sim900a, which is an industrial module produced by simcom company. It mainly supports the functions of short-term, communication, data flow on-line, voice call and fax. It has two working frequency bands. It is embedded with TCP / IP communication protocol, supports TCP / UDP communication and FTP / HTTP service, and can also be controlled by at command. The power supply mode is DC power supply, and the voltage value is generally between 5V and 24V. Under 12V power supply, the current value under normal GPRS communication is about 45mA, and the sleep state current is about 12mA. However, at the beginning of data transmission, the maximum instantaneous current is as high as 90mA, and the corresponding instantaneous current of sim900a is 2A / 4V. Under 80% conversion efficiency, the power input The instantaneous current of the terminal must not be less than 833ma / 12V, so when designing the circuit, pay special attention to the design of the power module circuit. In this design, the output is used to supply 12V DC switching power supply.