Design Of Seismic Data Real Time Transmission System Based On Wireless Ad Hoc Network

Microseismic monitoring is a method for observing microseismic events caused by hydraulic fracturing on the site of low-permeability oil and gas reservoir reconstruction based on a seismic signal acquisition system,and obtaining information such as fracture orientation,density,and dimension through real-time data processing.At present,the centralized network topology is mainly used for data transmission in microseismic monitoring activities at home and abroad.This technology uses a master(master)-slave(relay station)network structure to realize data transmission,but it has high transmission equipment costs and networking It is difficult to meet the real-time requirements of node seismograph and monitoring center data transmission due to the difficulty of data transmission and the limitation of rate reduction caused by multi-rate transmission.In response to the above problems,this article investigates and analyzes the performance indicators of the existing wireless communication technology in terms of communication distance,transmission rate,etc.,combined with the actual application requirements of microseismic monitoring,chooses to use the 802.11 ac Wi Fi communication standard,and passes on different Mesh networks To compare the topological structure,a node seismograph data transmission system based on wireless multi-hop ad hoc network is designed.This method eliminates the need for additional relay facilities for each node seismograph,but uses a multi-hop ad hoc network to complete the communication,effectively solving the problems of difficult networking and high routing overhead costs,and effectively reducing nodes The data transmission delay between the seismograph and the monitoring center meets the real-time requirements of the system.This paper designs a node seismograph data transmission system based on wireless multi-hop ad hoc network from both hardware and software.The hardware ofthe data transmission system mainly includes the main control with STM32F207 as the core,and data acquisition and wireless communication modules.Based on this hardware,the Free RTOS system is used to design the data transmission lower computer program of the ad hoc network based on the AODV(Ad hoc On-Demand Distance Vector Routing)routing protocol.At the same time,it has designed modules including node seismograph connection status monitoring,node seismograph data acquisition and transmission parameter configuration,seismograph equipment status information query and other modules,as well as a host computer monitoring platform based on FTP protocol for node seismograph data file recovery and processing.Related software development.Finally,the data transmission system designed in this article is tested,30 nodes are connected to the multi-hop ad hoc network to measure the network quality,and the data transmission system test is divided into two parts: one part is a functional test.It includes testing whether the entire data transmission system can realize the data acquisition function and data upload function of the node seismograph;the other part is the data transmission performance test,which mainly includes testing the network access efficiency of all node seismograph equipment and the data transmission of the entire data transmission link Speed and real-time.The test results show that the average transmission rate between hops of the node seismograph is 256kb/s-512kb/s,the average throughput rate of the transmission system is 8.9-14.6Mb/s,and within the allowable delay range,The return rate is over 85%.It can be seen from the test data: Compared with the traditional centralized network,the node seismograph data transmission based on wireless multi-hop ad hoc network proposed in this paper has better transmission performance and achieved the expected goal.