Environmental Detecting Data Acquisition And Transmission Technology

At present, water pollution, air pollution and noise pollution are the three main pollution around the world, they are also major environmental problems in china, among them, governance and control of water pollution in the previous years have been taken into account, for noise pollution and air pollution, in recent years, the relevant state departments began to attach importance to monitoring, prevention and control of noise pollution and air pollution.On the basis of the combination of independent research & development and absorbing foreign related technologies, China has researched and developed the related testing technique and launched numerous testing equipments, but the equipments price is very high, appearance is huge and they have poor mobility, cannot meet the current demand which is proposed by some departments and enterprises that testing equipments must have the characteristics of cheapness,mobility and flexibility. So this paper puts forward a set of environmental detection system, on the basis of continuous improvement, three generation products which can meet the above-mentioned low-cost, compact requirements have been rolled out and they can accurately detect noise parameters and dust parameters in monitoring points and upload the parameters to the monitoring computer, which can provide basis for the subject research related environment and the decision-making of the environmental protection departments.The main functions of the environment detection system are the detection of noise parameters and dust parameters in monitoring points and uploading them to the LAN or the Internet, on the basis of determining the overall scheme, it is given that the research& development processes from first generation product to the third generation product in detail, data network transmission schemes for each generation product are introduced, the advantages and disadvantages of each data network transmission scheme and the necessity of improvement are analyzed, at the same time, each generation detection extension is presented and its faults of internal layout and common problems of testing processes are also given,of course,solutions and improvement are given.In the meanwhile, the paper also introduces the each module in the system, including the data acquisition board, the power supply module, the noise sensor module, and the dust sensor module, and emphatically introduces the working principle of noise sensor and the noise meter used in this system; the paper also introduces the commonly used principles and detection methods of PM parameters, the detection principle and detection algorithm of the dust sensor used in this system are introduced in detail.Main work of this paper is collected data transmission, around the data transmission, the main transmission methods implemented are in the following:(1) It is tested and achieved that the collected data are transmitted to the specified domain name by the GPRS module; the principle of GPRS technology and the transmission processes are introduced in detail, for the domain name resolution, the analytic principle and analytic processes are described at length, in meantime, the advantages and disadvantages of the transmission mode are described and the detailed testing steps are given, ultimately, the data transmission is achieved successfully by GPRS module and DNS, but this transmission mode is only suitable for transmission testing, it is always limited in practical application and is not suitable for mature products.(2) It is tested and achieved that the collected data are transmitted to the specified IP address by the GPRS module; on the basis of transmitting collected data to the specified domain name by GPRS module, the specific processes and principle which the collected data are transmitted to the IP address directly are introduced in detail, finally it is achieved that collected data are transmitted to the Internet, through the testing, the data transmission mode is reliable and stable.(3) It is tested and achieved that the collected data are transmitted to the computer in the LAN by a serial port to Ethernet module; the serial port to Ethernet module is introduced, the module can realize conversion between a serial port to a Ethernet port so that we can avoid software development of the Ethernet port communication, the principle and implementation processes of the transmission mode are introduced at length, finally the data transmission mode is achieved.(4) It is tested and achieved that the collected data and video are uploaded to the LAN or the Internet by the serial port to Ethernet module, the camera and router(switches); on the basis of achieving data transmission by a serial port to Ethernet module, LAN communication principle and the specific setting processes of the transmission mode are described in detail, through the actual testing, the transmission mode can upload superposition data to the monitoring server on the LAN or the Internet stably. (5) It is tested and achieved that the RJ45 network communication between a data acquisition board and a computer by ENC28J60. Ethernet controller ENC28J60 and uIP protocol stack are introduced, and the principles of hardware connection and software are made a detailed introduction, the mechanical communication and response communication between a data acquisition board and a computer are achieved combined with processes, at last, patrol-style communication between two acquisition boards and a computer on LAN is achieved.