1、英文原文：http:/ Batchu Spandana et al. / International Journal on Computer Science and Engineering (IJCSE) Security Management System for Oilfield Based on GSM Technology Batchu Spandana M.Tech Student, Department of ECE Sri Vasavi Engg College, Tadepalligudem Addanki Purna Ramesh Ass
2、ociate Professor, Department of ECE Sri Vasavi Engg College, Tadepalliguem. P.Gopala Reddy Asst. Professor, Department of ECE Sri Vasavi Engg College, Tadepalliguem Abstract： Security Management at the industries mainly during the night times at the oil field is a critical task fo
3、r the security people. Checking for the oil thefting, power failure, temperature range checking, tilt checking of the tanks, leakage of oil by rotating the pump done by the thieves is a critical task for the security people. improve the security level by implantation of wireless embedde
4、d technology will solve this problem. By reducing the manual power, at the site locations, and by improving the security level with the help of GSM based wireless technology which consist of transmitter (GSM modem) at the site location and receiver is the GSM mobile. Information transmitted b
5、y the GSM modem at the plant location will be sent to the respective persons mobile as a text message. The security people will take appropriate action according to the problem. For this we are used LPC2148 (ARM7) based microcontroller, which is the current dominant microcontroller in
6、mobile based products and Software development tools as Keil, flash magic for loading hex file into the microcontroller. Keywords： LPC2148 (ARM7)； Embedded C； Keil； Flash magic； SIM 300 GSM Mode I. INTRODUCTION GSM technology has been used worldwide for almos
7、t two decades. At the end of rst quarter of 2007 there were 2,278,095,380 GSM subscribers, which represent almost 80.5% of all mobile network subscribers (Wireless Intelligence Organization informations； Scourias, 1995). With ra
8、pid development of national and international economic construction, there is a great demand and dependent on oil products ex: petroleum in various industries. The international price of oil has been kept at a high level in recent years, so improving production efficiency and wastage due to tilt, ov
9、er flow occur in valves, to protect oil from thefting on domestic oilfield is urgently needed to be improved. For protect and save oil products for 24 hours need huge human power, even also the implementation of safe management for oilfield is very difficult. We overcome these difficulties, b
10、y implementing a perfect scheme using GSM Technology. This system can improve the level of oilfield security. GSM is the pan-European cellular mobile standard (Scourias, 1995). Three considered speech coding algorithms are part of this standard. The purpose of these coders is to co
11、mpress the speech signal before its transmission, reducing the number of bits needed in its digital representation, while keeping an acceptable perceived quality of the decoded output speech signal. Spectrum efciency of the GSM transmission system is increased through the use of DTX (Discontinuous T
12、ransmission), switching the transmitter on only during speech activity periods. VAD (Voice Activity Detection) is used to decide upon presence of active speech. To reduce the annoying modulation of the background noise at the receiver (noise contrast effects), CNG (Comfort Noise Generation) is used,
13、 inserting a coarse reconstruction of the background noise at the receiver (Scourias, 1995). Additionally, GSM incorporates also non-standard modules such as Echo Cancellation, Noise Reduction, Speech Preemphasis and Automatic Gain Control. As mentioned earlier, there exist three different GSM speec
14、h coders, which are referred to as the FR (full rate), HR (half rate) and EFR (enhanced full rate). Their corresponding European telecommunications standards are the GSM 06.10 (1996), GSM 06.20 (1998) and GSM 06.60 (1997). These coders work on a 13 bit uniform PCM speech input signal, sampled at 8 k
15、Hz. The input is processed on a frame-by-frame basis, with a frame size of 20 ms (160 samples). II. SYSTEM STRUCTURE The security management system for oil field based on GSM Technology design is divided in to two sub systems (1) Transmitting section and (2) Receiving sec
16、tion. The transmitting system consists of (1) Sensor Unit, (2) LPC2148 (ARM7) Microcontroller, (3) SIM300 GSM Modem. Further the sensor unit is divided into five categories (a) TSOP1738 -IR transmitter and receiver as a tank over flow sensor (b) L7805 as a power failure in
17、dication unit (c) Limit switch as a Valve rotation unit (d) Mercury tilt switch as a Tilt sensor (e) LM-35Temperature sensor. The receiving section consists of GSM based Mobiles. Fig.1shows the Block diagram of the security management system for oil field bas
18、ed on GSM Technology. Fig.1 Block diagram of security management system for oil field based on GSM Technology The TSOP1738 -IR transmitter and receiver, L7805, Limit switch, Mercury tilt switch, LM-35 modules are interfaced to I/O ports of the LPC2148 (ARM7) M
19、icrocontroller. The LPC 2148 controller continuously monitors the tank level, tilt of the valve, angle of the valve rotation. If any change of parameters occurs at the corresponding modules the controller turns on buzzer, displays the message on LCD display and at the same time the controller activates the GSM Modem and GSM Modem sends the message to the two authorized persons by using GSM based wireless technology. Fig.2 Main circuit board without chassis
