Design Of Wireless Distributed Signal Synchronous Acquisition System Based On GPS Timing

With the continuous development of industrial production in the direction of modernization,high speed and systematization,the collection of vibration data plays an increasingly important role in the health monitoring of large buildings.In this paper,a distributed signal synchronization acquisition system is designed based on GPS timing and WIFI wireless communication.The GPS timing pulse is used to synchronously collect vibration acceleration signals and the WIFI wireless communication is used to complete the transmission of signals from the underlying hardware to the host computer software.The synchronous data is stored,processed and displayed by the host computer software.The related work is as follows:Firstly,the development status and trend of distributed vibration acceleration acquisition devices at home and abroad are analyzed,and the functional requirements of vibration acceleration acquisition devices are established.According to the functional requirements analysis,the power management module,synchronous timing module,wireless transmission module,PC software design and wireless sensor network topology are designed.Secondly,the hardware circuit and software program of distributed signal synchronous acquisition system based on WIFI and GPS timing are designed.The hardware circuit includes GPS timing module,WIFI wireless communication module,data acquisition module,power management module and microprocessor.The GPS module generates 1PPS timing pulse to realize synchronous data acquisition,the wireless transmission of data is realized by wireless sensor network composed of WIFI modules,the node is powered by rechargeable lithium battery and the node energy management is realized by fuel gauge monitoring,and then,the continuous and stable operation of nodes is ensured.The requirement of the tester to judge the operation of the node in real time according to the state of the display lamp is satisfied by display lamp circuit.The software design includes two parts: the lower computer embedded software and the upper computer software.The synchronous data acquisition is realized through clock interruption and various commands issued by the upper computer is completed through receiving interrupt coordination by the embedded software;The functions of receiving,processing,storing,waveform display and FFT analysis of synchronous data is realized by the upper computer software.Finally,the test experiment was designed in combination with the actual working environment,and the node function test in the laboratory and the outdoor test of the whole system were carried out on the whole system.At the same time,the synchronization of the system synchronization data is verified in the laboratory.By analyzing the time-frequency domain of the test data,the verification system can be used in the practical application of time difference positioning and natural frequency detection of the vibration object.