Multi-channel Vibration Signal Acquisition And Processing System With Realization

The Implementation of a Seismic Signal Detecting System is introduced in this thesis. In this system, up-to-4-channel data can be acquired by seismometers and then the data are transferred to targets in two ways: one way is to DSK through EMIF (External Memory InterFace) for application in field; the other way is to the remote monitoring center through RS-485 route and finally to PC via USB bus after converted by a USB/RS-485 adapter. In the monitoring center, up-to-4-channel real-time wave charts are displayed and stored on the software platform.This thesis mainly discusses the hardware design of the data acquisition system, the control logic design based on CPLD, the design of USB/RS-485 adapter and the development of the PC platform software.The data acquisition system consists of the signal conditioning circuit, DSK interfacing circuit, RS-485 communication interfacing circuit, system clock circuit, the power circuit, and so on. The core component of the system is a CPLD, based on which the A/D control logic, UART serial logic, EMIF interface logic, and DEBUG logic are implemented.USB/RS-485 adapter is designed to implement bidirectional interfacing between USB and RS-485.The concept "Virtual Instrument" is adopted in the application software designing on host PC. The software modules, including communication module, wave chart displaying module, signal analyzing and processing module, are developed on the platform of LabVIEW.The whole design is based on the Unattended Ground Sensor (UGS) system.