基于PSK卫星通信的水文信息终端设计

【作者】 邱荣荣；

【导师】 柏连发；

【作者基本信息】 南京理工大学 ， 光学工程， 2008， 硕士

【摘要】 水文遥测技术是利用计算机技术和通信技术对水文要素进行自动采集、传输和处理的专门技术,为水情预报和防洪调度提供准确及时的水文信息。在水文遥测系统的建设过程中,由于投资、适用范围及管理渠道的不同,不可避免地形成各式各样的系统,其最大的差异体现在水文遥测数据传输信道的不同。论文在对现有的水文测报系统深入研究的基础上,讨论了现有的几种水文数据传输信道的优点和可能存在的不足,采用了基于PSK卫星通信的水文信息终端设计方案;设计了由单片机、串口扩展模块、数据接口模块、GPS模块、实时时钟模块、调制模块和混频锁相环模块组成的硬件系统;论文还完成了实现各个模块功能的相关软件设计。系统选取单片机AT89S52作为主控器件,用于接收上位数据采集系统的水文数据,然后通过调制芯片AD7008进行PSK调制,最后通过混频锁相环搬高到400MHz载频上发送。系统采用节电运行模式和实时时钟定时唤醒的设计解决了功耗问题,还采用GPS技术实现系统的精准校时,在时间上实现了与监测中心的同步。更多还原

【Abstract】 Hydrological telemetering system is an expertise using computer technology and communication technique to achieve data acquisition, transmission and processing. It can provide precise and prompt hydrological information to regime prediction and flood control operation. In the process of hydrology telemetry system’s construction, with the difference of invests and manages, there are all kinds of system in the practice use inevitably. Its biggest difference lies in the transmission channel of hydrological information.The thesis based on the investigation and analysis of the existing transmission channels of hydrological data, which have solved the question and possibly existed insufficiency, then adopted a solution of terminal design of hydrological system using satellite communication based on PSK modulation. The thesis designed the hardware system and software system to realize it. The hardware contains MCU,the GPS module, the expansion of serial port, the data interface, the real-time clock, the modulation module and the phase locked loop. The system choices AT89S52 as the main control device, It receives the hydrological data from the front detector and modulates the data with PSK modulation by AD7008. Then adds the modulated signal to the carrier frequency of 400MHz by the phase locked loop and transfers the synthetic signal by satellite. The system was designed that it worked in low-power mode after the task and was waked up by the real-time clock, so it can save power effectively. In addition, in order to keep synchronization with the monitor center, the system receives the time data from the GPS satellite and corrects the real-time clock.更多还原