It is a multi-hop self-organizing network system formed by wireless communication means, which is deployed in the monitoring area and consists of a large number of inexpensive micro sensor nodes. Its purpose is to collaboratively sense, collect, and process information about perceived objects in the network coverage area and send it to the observer.
Three elements of a sensor network: sensors, perceived objects, and observers
Research and development of sensor networksThe study of sensor networks started in the late 1990s. Since the beginning of the 21st century, sensor networks have attracted great attention from academia, military and industry. The United States and Europe have launched many research projects on wireless sensor networks.
1. In the military field: The US Department of Defense and various military departments have begun research on sensor networks.
2. In the civil field: The US Department of Transportation proposed the “National Intelligent Transportation System Project Planning†in 1995, which is expected to be fully operational by 2025.
3. Academic circles: The American Natural Science Foundation of China established a wireless sensor network research plan in 2003.
4. Since 2004, more universities and scientific research institutions have joined the research work in the field.
Detecting thermal, infrared, sonar, radar, and seismic signals in the surrounding environment by means of sensors built into the nodes to detect temperature, humidity, noise, light intensity, pressure, soil composition, size, speed and direction of moving objects, etc. Material phenomenon.
Computer network technology represented by the Internet is a great achievement of computer science in the twentieth century. It has brought profound changes to our lives. However, in terms of network functions, the network world is richer, and it is virtual. It is still separated from the real world we live in. In the online world, it is difficult to perceive the real world. Many things are still impossible. The times call for new network technologies. Sensing network is a new network technology that emerged in this context. It integrates sensors, low-power, communication, and micro-electromechanical technologies. It is foreseeable that in the near future, sensor networks will give us Lifestyle brings revolutionary changes.
Key technologies and features of sensor networksKey technologies of WSN: network topology control, network protocol, network security, time synchronization, location technology, data fusion, data management, wireless communication technology, embedded operating system, application layer technology.
Features: large-scale network, self-organizing network, dynamic network, reliability network, application-related network, data-centric network.
Main application areas of sensor networksMilitary applications, environmental observation and forecasting systems, medical care, smart homes, building condition monitoring, and other applications (such as space exploration, smart dust, etc.).
The concept of The Internet of Things was introduced in 1999. Its definition is simple: all items are connected to the Internet through information sensing devices such as radio frequency identification for intelligent identification and management. The Internet of Things is called the third wave of the development of the world information industry after computers and the Internet through the application of intelligent sensing, recognition technology, ubiquitous computing, and ubiquitous networks. The Internet of Things is regarded as the application expansion of the Internet. Application innovation is the core of the development of the Internet of Things. Innovation 2.0, with user experience as the core, is the soul of the development of the Internet of Things.
The principle of the Internet of ThingsThe Internet of Things is based on the computer Internet, using RFID, wireless data communication and other technologies to construct an "Internet of Things" that covers everything in the world. In this network, items (goods) can “communicate†with each other without human intervention. Its essence is to use the radio frequency automatic identification (RFID) technology to realize the automatic identification of items (goods) and the interconnection and sharing of information through the computer Internet.
And RFID is a technology that allows items to "talk". In the concept of "Internet of Things", RFID tags store standardized and interoperable information, and automatically collect them into the central information system through wireless data communication networks to realize the identification of goods (goods), and then through open The computer network realizes information exchange and sharing, and realizes "transparent" management of items.
The advent of the concept of "Internet of Things" broke the traditional thinking of the past. The idea of ​​the past has been to separate the physical infrastructure from the IT infrastructure: on the one hand, airports, roads, buildings, and on the other hand, data centers, personal computers, broadband, and so on. In the "Internet of Things" era, reinforced concrete and cables will be integrated into chips and broadband as a unified infrastructure. In this sense, the infrastructure is more like a new earth site, and the world is operating on it. Including economic management, production operations, social management and even personal life.
Characteristics of the Internet of ThingsThe first is comprehensive perception, that is, using RFID, sensors, two-dimensional codes, etc. to obtain information of objects anytime and anywhere;
The second is reliable transmission, through the integration of various telecommunication networks and the Internet, the information of the object is accurately transmitted in real time;
The third is intelligent processing, using cloud computing, fuzzy recognition and other intelligent computing technologies to analyze and process massive amounts of data and information, and implement intelligent control of objects.
Internet of Things is widely used in intelligent transportation, environmental protection, government work, public safety, safe home, intelligent fire protection, industrial monitoring, environmental monitoring, street lighting control, landscape lighting control, building lighting control, square lighting control, elderly care, personal Health, flower cultivation, water monitoring, food traceability, enemy investigation and intelligence gathering.
The development trend of the Internet of ThingsThe Internet of Things will be the next "important productivity" to promote the rapid development of the world, and it is another trillion-level market after the communication network.
Industry experts believe that the Internet of Things can improve economic efficiency and save costs on the one hand; on the other hand, it can provide technical impetus for the recovery of the global economy. The United States, the European Union, etc. are investing heavily in research to explore the Internet of Things. China is also paying close attention to and attaching importance to the research of the Internet of Things. The Ministry of Industry and Information Technology, together with relevant departments, is conducting research on a new generation of information technology to form policy measures to support the development of next-generation information technology.
In addition, after the popularization, the number of sensors and electronic tags and supporting interface devices for animals, plants and machines, and articles will greatly exceed the number of mobile phones. The promotion of the Internet of Things will become another driver for promoting economic development, opening up another potential development opportunity for the industry. According to the demand for the Internet of Things, hundreds of millions of sensors and electronic tags are needed, which will greatly promote the production of information technology components and increase the number of employment opportunities.
1. In a broad sense
The composition of the Internet of Things and the sensor network are basically the same, and they are different expressions of the same thing. The Internet of Things is closer to the essential attribute of the "object" than the sensor network, emphasizing that information technology and equipment provide a higher level for "things". Application service; sensor network (sensor network) is an objective description from the perspective of technology and equipment, and the elements of equipment and technology are obvious.
For example, the sensor network is a scientific name, the Internet of Things is a common name; or the sensor network is a big name, the Internet of Things is a nickname.
2, from the perspective of industry and users
It is called the Internet of Things: from a technical support point of view, it is called a sensor network. The Internet of Things and the sensor network are the same thing, and its essence is the sensor network.
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