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智能 环境 监控 系统 设计

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智能环境监控系统设计,智能,环境,监控,系统,设计

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Application of WSN in precision forestry Zhang Qinghui Li Junqiu Rong Jian Xu Weiheng He Jinping Department of Computer and Information Science, Southwest Forestry University.650224 Kunming, China Email: huizq13 Abstract In order to conveniently access information of forestry, a new technology, wireless sensor network is introduced in precision forestry applications. A forestry information monitoring system based on wireless sensor network technology is proposed, which can sample temperature, soil moisture, light intensity, nitrogen concentration and other environmental factors. The networks of sensor nodes are managed by a central node which collects and transmits data to remote host computer through GPRS. The system design methodology based on ZigBee chip 2430 is presented and the corresponding system hardware architecture and software flow aregiven. This system effectively makes it easy to collect and transmit data of environmental factors in forestry product and posses high practical values. Keywords precision forestry, wireless sensor network, zigbee, CC2430. I. INTRODUCTION With the rapid development of a series of high technologies such as information technology, biotechnology and engineering technology, the concept “Precision Forestry” introduced in early 90s is becoming increasingly important. The word, precision forestry is a forestry production process in which high technologies such as visual sensors, satellite positioning and other high-tech sensing and analytical tools are used to obtain the immediate data about work quality, quantity and timing, and by analyzing environmental factors affect the growing of forestry, technically feasible and economically effective control measures are taken to achieve maximum benefits and minimum environmental hazards 1. Currently, the development of precision forestry has lagged behind the development of precision agriculture. It is due to some features such as longer cycle, more interference, more variation and more complex conditions, in forestry production 2. These features make the collection and transmission, which is an important part of precision forestry, of environmental factors in tree growth becomes very difficult. Therefore, a forestry ecological environment monitoring system with the features of low-input, low-energy, low-consumption, high-output, high-intelligence, high-information and high-protection of environment should be developed. Now, the emergence of a new technology, wireless sensor network, provides a suitable technical means for the realization of this goal. II. WIRELESS SENSOR NETWORK Wireless sensor network, which integrates sensor technology, MEMS technology, wireless communication technology, embedded computing technology and distributed information management technology, has been under rapid development during recent years. Because of the wide application prospect, it interests the world. “Business Week” ever predicted in 1999 that WSN technologies would be one of the most important technologies in 21st 3. ZigBee is a low-power wireless communications technology designed for monitoring and control of devices. It is generally considered as an optimal wireless communication protocol, because it fully meet the requirement of WSN application and owns such property as higher reliability, self-organization network, self-cure capacity and large network volume 4. One of ZigBees key features is its ability to cover large areas with routers. This feature helps differentiate ZigBee from other technologies. Mesh networking extends the range of the network through routing, while self healing increases the reliability of the network by re-routing a message in case of a node failure. III. SYSTEM ARCHITECTURE As the Figure 1 shown, the ZigBee wireless network system adopts the Mesh topology. The sensor nodes achieve real-time data such as temperature, humidity, soil moisture, and nitrogen concentration, and transmit data to the central node, coordinator. While the sensor node is far away from the central node, the every other node can acts as ZigBee router which is able to relay data to central node. All of the data are directed to the ZigBee coordinator by which these data are combined and packed and then transmitted to the host computer through GPRS networks allowing information to be transmitted more quickly, immediately and efficiently across the mobile network. On the host computer, the received data are monitored, Fig.1 System architecture calculated, analyzed and evaluated by an expert system. Based on ZigBee and GPRS, this design method in which the ZigBee nodes are waken up periodically, effectively reduces the power consumption of each ZigBee sensor nodes and the probability of collisions with each other. The PC acts as host computer and with which the Ethernet interface is used to realize remote monitor 5. IV. HARDWARE CIRCUIT DESIGN A. ZigBee chip The hardware of this system includes two parts: one is the sensor nodes which are responsible for data acquisition; the other is central node which is responsible for wireless network management and data transmission and framing. All of the two parts take CC2430 as the core of the wireless transceiver and processing module. The CC2430 is a true System-on-Chip (SoC) solution specifically tailored for IEEE 802.15.4 and ZigBee. applications. It combines a very excellent transceiver core with an industry-standard enhanced 8051 MCU, 32/64/128 Flash, 8KB RAM, ADC, several timers, AES security coprocessor, watchdog timer, two USARTs, and many other powerful features6. Because of requiring minimal external circuitry support, the CC2430 is very convenient to use. And taking the most significant advantage of low power consumption, the CC2430 which has less than 0.6A current consumption in standby mode, is very suitable for battery applications. B. ZigBee hardware circuit endpoints The hardware block diagram of sensor nodes and central node is shown in Figure 2. As mentioned above, the CC2430 is very rich in internal resources, so the core hardware is very simple. Except for MCU chip, CC2430, the whole hardware of sensor nodes just consists of three parts: sensor circuit, power supply, crystal Oscillator. Similarly, the central node is composed of three parts: GPRS module, power supply, crystal Oscillator. Therefore, the hardwares size of both can be made very small. Fig.2 Block diagram of hardware . CC2430 integrates a 14-bit ADC with up to eight inputs. Thus, a node can sample a variety of data. If the number of input is more than 8 or the control circuit is very complicated, an additional MCU and ADC can be added to perform the corresponding functions. The MCU can communicate with CC2430 through RS232 serial interface. The central node periodically wakes sensor nodes up, and collects data from these nodes. And then, central node packets these data in accordance with predefined format and pass these data through the serial port to GPRS module. Finally, host computer get these data. And then expert system process and graphically display these data. ZigBee communication is working at 2.4G band, the antenna is also used in the realization of microstrip line on the PCB to achieve. Therefore, in the PCB design, must be strictly reference manual; placement and routing, we should also pay attention to split the analog and digital signal processing. V. SOFTWARE DESIGN A. CC2430 firmware design The CC2430s firmware, based on TI Z-Stack, is developed under the IDE platform, IAR Embedded WorkBench. Z-Stack released by TI is a protocol stack in accordance with ZigBee 2006 specifications. With the help of Z-Stack, our development of the firmware is mainly about application layer. In our system, central node is initiated as ZigBee coordinator and sensor nodes are initiated as ZigBee router. Coordinator is the center of the entire network, which is responsible for functions including the establishment, maintenance and management of networks, and allocation of network address. The software flow chart of coordinator is shown in Figure 3. Fig.3 Flow chart of coordinator At first, software initialize clock circuit, UARTs and IO port, and then physical layer, MAC layer, set PANID, channel and addresses to build a network. After initialization done, the coordinator monitor RF signal and assign network number to new node. Meanwhile central node enables an internal timer. When timer expires, an interrupt service routine is called to wake up sensor nodes. And then central node waits for data received interrupt. After all data have been collected, central node sends these data through RS232 serial port to GPRS module which wirelessly forwards real-time data to host computer through GPRS. The software flow chart of sensor nodes is shown in Figure 4. Sensor nodes hardware initialization is similar to central nodes. After joining the network, sensor nodes enter sleep mode, waiting for wakeup command. As soon as get wakeup RF signal, sensor nodes sample signal and transmit data to central node, and then go back to sleep mode. Fig.4 Flow chart of sensor nodes The data transmitted between central node and the sensor nodes, or between central node and host computer, is in accordance with a customized frame structure which is shown in Table 1. Table 1 Frame structure Node Transfer Function Header NO. node NO. NO. Data Checksum 8bit 8bit 16bit 8bit 16bit 8bit The sensor nodes periodically get environmental data and packet these data, and then transmit data to central node which transfer these data to host computer. As soon as these data being received, host computer analyze them and graphically demonstrate them in user interface. The following source code fragment is the sending function of the sensor node, which is periodically waken up by central node. And, if it gets the send command, the node packets collected data in format according to Table 1 and send the frame to physical layer program which wirelessly sent data to central node. void WirelessSendData(BYTE frame) . switch (frame) . case Packet_Send: SendData1 = 0xff; SendData2 = 0xff; SendData3 = macInfo.longAddr0; SendData4 = macInfo.longAddr1; SendData5 = 8;/data length is 8 for(i=0;i=5;i+) cs+=SendDatai; SendData6 = cs;/checksum SendData7=(Paket.Head) ; SendData8=(Paket.Node); SendData9=(Paket.ForwardNode); SendData10=(Paket.SensorNum); SendData11=(Paket.HighData); SendData12=(Paket.LowData); SendData13=(Paket.End); MACPutArray(SendData, 14); MACFlush(); break; case . . B. Software design of host computer Program of host computer is developed in LabWindows CVI which makes it easy to collect data and illustrate data on graph 7. The software, whose flow chart is shown in Figure 5, record, analyze and compare collected data, and graphically display on screen. Fig.5 Flow chart of host computer The main graphical user interface of host computer is shown in Figure 6. There are several buttons placed on the right of the panel. The user can observe and compare, in graphical way, the same environmental parameter of different sensor nodes by clicking on the buttons. Figure 7 illustrates temperature wave of four sensor nodes in 12 hours. . VI. CONCLUSION Fig.6 Main user interface Taking advantages of the ZigBee wireless sensor network, this system which is low-cost, low power consumption, intelligent, easy to maintain, low environmental pollution, accomplish monitor of environmental parameters in forestry areas. Moreover, just by adding appropriate sensors, the system which is expected to achieve more functionality, is easy to be extended in remote control and automatic control. It is the technologic features of wireless sensor network make it is ideal for applications in forestry production. Supposing the WSN is combined with 3S technology very well, it is bound to provide excellent technical support for the change of precision forestry from theory to practical. REFERENCES 1 ZHANG H CH, ZHOU H P, ZHENG J Q.Development and application prospects of precision forestryJ. World Forestry Research, 2004,17(5): 13-16. 2 NIE Y Z, MA X J, FENG ZH K, W H L.Design and practice in the system of precision forestryJ. Journal of Beijing Forestry University, 2002, 24(3): 89-93. 3 ZHANG Y ZH, XUE D Y, WU CH D, et al. Design and implementation of a wireless sensor network nodeC.Proceedings of 2008 IEEE International Conference on WiCOM,2008:1- 4. 4 LI J Q, ZHANG Q H, RONG J, et al.Application of ZigBee Technology in Precision ForestryJ. Journal of Agricultural Mechanization Research, 2010,32(7):185-188. 5 ZHANG Q H, LI J Q, ZHANG H X, et al. The design of environmental monitoring system based on ZigBeeJ. Journal of Foreign Electronic Measurement Technology,2010, 29(1): 46-48. AUTHOR BIOGRAPHY Zhang Qinghui was born in NanChong, China, in 1974. He received MS from UESTC, China.in 2002. Now he is an associate professor in department of computer and information science, southwest forestry university. His research interests include WSN and embedded system. Fig.7 Temperature waveforms of nodes In addition, user can get all environmental parameters of one specific node by clicking the round buttons, marked by digital number, in the map. Figure 8 shows temperature, humidity, illuminance and concentration of carbon dioxide of node 2. Fig.8 Waveform of node 2 . 淮 阴 工 学 院毕业设计（论文）任务书系 （院）：计算机工程学院专 业：通信工程学 生 姓 名：徐 江学 号：1081302227设计(论文)题目：智能环境监控系统设计起 迄 日 期:2012年2月13日2012年5月30日设计(论文)地点:淮阴工学院指 导 教 师:胡荣林专业负责人:赵建洋 发任务书日期:2012年1月7日 毕 业 设 计（论 文）任 务 书1本毕业设计（论文）课题应达到的目的： 本课题根据本科生的学习和科研能力进行选题。重点使学生学习有关无线传感器网络、嵌入式系统、单片机C语言编程、Visual C+6.0软件开发等理论知识，掌握相关技术的基础上掌握系统硬件和软件的开发和调试的技能。使学生通过学习和研究基于ZigBee的无线传感器网络组建和对环境的控制，基于VC+的上位机软件的开发，完成节点数据的远程传输，节点对执行器的自动化控制；上位机软件对接收到的数据进行处理和对节点进行控制及嵌入式软件编写。通过本课题这一开发应用过程强化学生在校所学的各种专业知识，培养解决工程问题的初步能力。2本毕业设计（论文）课题任务的内容和要求（包括原始数据、技术要求、工作要求等）：任务内容：1、 学习和掌握无线传感器网络、嵌入式系统、单片机C语言编程、Visual C+6.0软件开发等相关课程内容；2、 研究和理解ZigBee协议无线通信协议；3、 研究和完成节点嵌入式软件编写；4、 完成用Visual C+6.0开发的上位机软件；5、 掌握软件和硬件之间的调试方法；6、 完成毕业论文。任务要求：1、 收集有关无线传感器网络、智能传感器控制、Visual C+开发与调试技术等书籍、文献资料，在消化吸收相关技术的基础上开发智能环境监控系统，要求能够实现节点对环境参数出现异常时自动的控制执行器使环境参数到正常范围。上位机软件可以查看每个节点的实时数据和历史数据，查看网络的拓扑结构。设定环境参数的上下限，并且能够人为的打开或关闭各个执行器。2、 按照淮阴工学院对毕业设计（论文）的要求，完成相关外文资料的翻译工作、毕业设计（论文）的撰写、装订以及答辩等工作。毕 业 设 计（论 文）任 务 书3对本毕业设计（论文）课题成果的要求包括毕业设计论文、图表、实物样品等： 完成符合课题要求的软硬件系统；按要求撰写1万字（不含代码）以上的毕业设计论文 。4主要参考文献：1刘永强,郑宾.用于环境监测的无线传感器网络节点设计J.数字通信世界,2008年:81-83.2杨光,杨波.面向环境监测的无线传感器网络节点设计.单片机与嵌入式系统应用,2008年,第3期:38-40.3蒋勋,邹坚敏.无线传感器技术与展望J. 无锡南阳学院学报,2007年6月,第6卷第2期:30-32.4 李战明,李泉,殷培峰.基于Zigbee的环境监测无线传感器网络节点设计J.电子测量技术, 2010年06月,第33卷第6期:188-122.5杨京.ZibBee技术在远程监控系统的应用研究D.武汉科技大学,2010年5月. 6 王素红.基于Zigbee标准的无线传感器网络监控系统设计J.网络与通信,2008年9月18日:72-74.7 顾振宇.无线传感网国内外现状OL. 2010年09.14/publish/portal0/tab1023/info5999.htm8何成平.基于无线传感网络的设施农业智能监控系统J.常州轻工职业技术学院学报，2009年12月:22-279荆琦,唐礼勇,陈洲峰,王昭.无线传感器网络应用支撑技术研究J.计算机科学，2008,35(3):22-2610 Edoardo Biagioni,Kim Bridges.The Application of Remote Sensor Technology to Assist The Recovery of Rare And End