【作者】 解子亮；

【导师】 武杰；

【作者基本信息】 中国科学技术大学 ， 物理电子学， 2011， 硕士

【摘要】 近些年来,用于石油地震勘探的地震数据采集系统开始逐步引入无线传感器网络技术。但是目前适合石油地震勘探的无线传感器网络技术尚不成熟,存在着各种各样的问题。作者所在实验室研发的大型全数字地震仪系统也开始加入无线传感器网络,以便满足石油地震勘探中地震数据采集的各种需求。本文在调研了无线传感器网络和学习分布式无线数据采集实现过程中所用到的器件资料的基础上,初步实现了分布式无线数据采集系统的原型,并对数据采集站体进行了多项测试和测试结果分析。具体所做工作和测试内容如下所述。设计完成了分布式无线数据采集平台主控系统。包括微处理器、可编程时钟合成器、电源模块等的硬件配置,以及对微处理器的驱动配置。通过在该平台中加入数据采集模块和无线通讯模块,并对这两个模块进行了软件配置,初步实现了分布式无线数据采集系统的原型。在对分布式无线数据采集站体数据采集模块的整合基础上,实现了对数据采集模块的测试。采集站体的采集模块使用的ADC是ADS1282。完成了对ADC的软件配置、被测信号的数据采集和AD性能测试软件的编写。通过AD测试,这款ADC的通道噪声RMS值为1.59 uV,谐波畸变为?109.1 dB,动态范围为120.8 dB,测试结果表明该ADC的性能满足地震数据采集的需求。通过对分布式无线数据采集站体无线通讯模块的整合,实现了站体之间的无线通讯。该模块核心是CC1101。通过编写CC1101的驱动配置及测试代码,实现了站体之间的无线通讯,并进行了无线通讯测试。累计无线通讯测试时间约为2000分钟,无线通讯误码率小于9.5×10^-10,表明无线通讯稳定可靠。在初步完成分布式无线数据采集系统的原型基础上,实现了一种用于分布式无线数据采集单元之间的时钟同步方法。通过无线通信用CPU的计数器记录站体之间发送接收数据包的时刻来实现时钟同步,通过无线通信用CPU的DAC调节压控振荡器来进一步提高时钟同步精度。并在主从机时钟同步和时钟没有同步两种情况下,进行了分布式数据采集和分析对比。在本文时钟同步测试中,时钟同步时主从机信号同步精度达到0.061ms,比时钟未同步时的1.27ms改善了很多。测试结果表明时钟同步对于提高分布式采集数据的同步性具有十分重要的意义。总之,本文初步实现了石油地震勘探中的分布式无线数据采集系统原型,为实验室的大型全数字地震仪系统研发项目中加入分布式无线数据采集网络做了一定的准备和铺垫工作。更多还原

【Abstract】 In recent years, seismic data acquisition system for seismic exploration for petroleum began to gradually introduce wireless sensor network technology. But now wireless sensor network used for the oil seismic exploration is not yet mature, and there are kinds of problems. Large full digital seismograph system which is researched and developed by the laboratory where the writer works has begun to join the wireless sensor network to meet the oil seismic exploration in the seismic data acquisition needs.Based on investigation on the wireless sensor networks and the study of the devices used in the realization of the distributed wireless sensor networks, this paper realizes initially the prototype of the distributed wireless data acquisition system, and has a number of tests on the data collection station and analyses the test results. The specific content of the work and testing is described as below.Design and complete distributed wireless data acquisition platform for controlling system, Include the hardware configuration of microprocessor, programmable clock synthesizer, power module and the driven configuration of the microprocessor. By adding the platform data acquisition module and the wireless communication module, and the software configuration of the two modules, the initial prototype of the distributed wireless data acquisition system is realized.Based on integration of data acquisition module of the distributed wireless data acquisition station, the test on the data acquisition module is realized. The ADC used in the data acquisition module of acquisition station is ADS1282. The software configuration of ADC, data acquisition of the tested signal, and the test software for ADC performance are all completed. Through the AD test, the RMS value of the ADC channel noise is 1.59 uV, harmonic distortion is 109.1 dB, dynamic range is 120.8 dB. The test results show that the performances of the ADC meet the demand for seismic data acquisition.Through the integration of wireless communication module of he distributed wireless data acquisition station, the wireless communication is realized between the stations. The core of the module is CC1101. By writing the driver configuration of CC1101 and test codes, the wireless communication is realized between the stations and the test for wireless communication is done. The total time for wireless communication test is about 2000 minutes, and the wireless communication error rate is less than 9.5×10^-10. This is shown that the wireless communication is stable and reliable.Based on the initial completion of the prototype of distributed wireless data acquisition system, a method used for clock synchronization between distributed wireless data acquisition units is realized. Through wireless communication the timers of CPU record the time of sending and receiving data packets between the stations to achieve clock synchronization. Through wireless communication the DAC of CPU adjusts the voltage of VCXO to improve the accuracy of clock synchronization further. In the two cases that the clock of the master and slave is synchronized or not, the distributed data acquisition, analysis and comparison are done. In this test of clock synchronization, the accuracy of clock synchronization of signal in master and salve station when clock is synchronized is 0.061 ms, which is better than 1.27ms when clock is not synchronized. The results show that the clock synchronization is very important for improving the synchronization of distributed data acquisition.In summary, the prototype of distributed wireless data acquisition system for oil seismic exploration is initially realized in this paper. And all of these have done a certain amount of preparation work for adding a distributed wireless data acquisition network to large full digital seismograph system development project of the laboratory.更多还原