无线遥测式数字地震仪关键技术

介绍了一种完全自主开发的便携无线遥测式浅层数字地震仪.系统以无线自组网为核心,基于双ARM和FPGA平台,采用多功能IP软核驱动方式及嵌入式操作系统,从硬件方面提高系统的集成化程度,缩小设备体积.设计可动态配置信号调理单元保证系统前端的动态范围和保真性,采用并行双缓存循环预采集存储技术,实现不确定传输延时情况下的多道严格并行采集.文中详细分析了适合于地震数据传输的无线射频和无线以太网两种传输方式,以及相应的组网方案和关键技术难点,解决了分布式无线信号采集站的采集同步和非均匀采样问题.信号采集站单站集成12路并行采集道,各通道在4 k采样率时有效分辨率达18位,且参数可远程配置.软件中所集成的现场质量控制功能,非常适于复杂环境下的工程勘探,且由于移除了多个附加配件,从而缩小了设备的体积和重量,降低施工布线的复杂性,提高环境适应能力和勘探效率.

Key techniques of wireless telemetry digital seismograph

A portable wireless telemetry shallow digital seismograph which is completely independently developed is introduced in this paper. It takes wireless ad hoc network as the core of the system, based on double ARM and FPGA platforms. The multi-function IP soft core driver mode and embedded operating system are adopted to improve the integration level and to reduce the size of the equipment in the aspect of hardware. A dynamic and configurable signal conditioning unit is designed to ensure the dynamic range and fidelity of the system. And the technology of parallel double buffer including the circulation pre-acquisition and storage is applied to realize strictly multichannel parallel acquisition under the condition of uncertain transmission delay. This paper analyzes wireless radio and wireless Ethernet in details, which is suitable for seismic data transmission, and the corresponding networking scheme and key technical difficulties. The problems of acquisition synchronization and non-uniform sampling to distributed wireless signal acquisition station are solved. Twelve parallel acquisition channels are integrated to each signal acquisition station, which can reach 18-bit resolution with a 4 k sampling rate, and its parameters can be configured remotely. The field quality control function is integrated in the software that is suitable for engineering exploration in complicated environments. The size and weight of this equipment are reduced, and the complexity of construction layout is decreased since various additional accessories are removed. In doing so, the environmental adaptability and exploration efficiency of the equipment are greatly improved.