外文翻译--无线通信技术在电网通信中的应用前景

1、.中文7900字英文文献：The application prospects of wireless communication technology in the grid communicationTechnical Analysis of the thesis Keywords wireless; grid communication;Abstract With the rapid development of modern science and technology to build the perfect strong and reliable communications net

2、work, has become increasingly important. The articles combine the characteristics and needs of the electric power communications and wireless features of the new technology, analyze the application prospects of wireless communication technology in the power grid communications.First, an overviewElec

3、tric power communication network is run in order to ensure the security and stability of power system came into being. With the power system security and stability control systems, dispatching automation system is collectively known as the power system security and stability of the three pillars. Ch

4、ina's electric power communication network through the construction of several decades of ups and downs, has begun to take shape, build and become interchange communication network via satellite, microwave, carrier, cable and other means of communication. With the development of wireless communi

5、cation technology, wireless communication system characteristics change dramatically. In recognition of the wireless communication network is not dependent on the grid grid, and strong resistance to natural disasters, but also has large bandwidth and transmission distance, non-line-of-sight transmis

6、sion, etc., is very suitable to make up for the communication of single coverage incomplete surface defects . This paper briefly describes the application characteristics, advantages and disadvantages of wireless communications transmission system, and analyze the prospects of its application in pow

7、er system. Complete network transmission system based on the future development trend of the sensor network towards the network to further improve the technology - the application of the sensor network technology and network support. Promote the application of sensor networks from the perspective of

8、 the manufacturing of sensor node hardware platform, network application technology development to real-world applications into; network support techniques include positioning technologies, synchronization technology, security technology, within the network information processing technology, to netw

9、ork performance enhance the main objective to improve overall network quality of service and intelligent.Within the network, information processing technology is designed packaging further integration of the original data collection, information processing and computing migrate to within the sensor

10、network, which simplifies the equipment requirements on the client, the user side can be perceived to use more low-end and simple equipment read and apply information. Network information processing technology allows the sensor network has a more advanced, better information processing capabilities,

11、 available to the user's perception of the information will be easier to understand.Second, the wireless technology introduced(A) the concept of wireless communication technologyCurrently, wireless communications and its applications has become one of the most active areas of research in the inf

12、ormation science and technology today. The general by the wireless base stations, wireless terminal and application server.(B) the development status of wireless communication technologyWireless communications technology in accordance with the transmission distance can be roughly divided into the fo

13、llowing four technology based on IEEE802.15 wireless personal area network (WPAN), wireless metropolitan area network based on IEEE802.11 wireless local area network (WLAN) based on the IEEE802.16 ( WMAN) and IEEE802.20-based wireless WAN (WWAN).Overall, the representatives of the long-distance wire

14、less access technologies: GSM, GPRS, 3G; on behalf of the short-range wireless access technologies, including: WLAN, UWB. Can be divided in accordance with the mobility of mobile access and fixed access. Fixed wireless access technology: 3.5GHz wireless access (MMDS), Local Multipoint Distribution S

15、ervice (LMDS), 802.16d; mobile wireless access technologies including: 802.15 of WPANs, 802.11 WLAN, 802.16 e WiMAX, 802.20 WWAN. In accordance with the bandwidth can be divided into narrow-band wireless access and broadband wireless access. Representatives of which broadband wireless access technol

16、ogies 3G, LMDS, WiMAX; narrow-band wireless access technology on behalf of first-and second-generation cellular mobile communication system.A major wireless communications technologyFrom technology trends can be seen as the core of the OFDM + MIMO wireless communications technology will become the m

17、ainstream of the development direction of future wireless communications. The current wireless communications technology based on this technology are: four kinds of B3G, WiMAX, WiFi, of WMN and other technologies.Other wireless communications technologyIn addition to the mainstream wireless communic

18、ations technology, wireless communication technology also includes: IrDA, Bluetooth, the RFID, UWB, cluster communications, and other short-range communications technology and on LMDS, MMDS, and point-to-point microwave, satellite communications, long distance communication technology.(1) the IrDA:

19、Infrared Data Association, is a point-to-point data transfer protocol, the communication distance is generally between 0 1m, the fastest transfer rates up to 16Mbps, the communication medium for the near-infrared wavelengths around 900 nm.(2) Bluetooth: Bluetooth in the global open 2.4GHzISM band us

20、ing frequency hopping spread spectrum technology, the communication medium of electromagnetic waves from 2.402GHz to 2.480GHz.(3) of RFID: Radio Frequency Identification, ie, radio frequency identification, commonly known as labels. It is a non-contact automatic identification technology, automatic

21、target recognition by the RF signal and access to relevant data. RFID tags, Interpretation of three basic elements, and antenna.(4) the UWB: Ultra Wideband, Ultra-Wideband technology. UWB communication is also known as carrier-free baseband communications, and is almost fully digital communications

22、systems, RF and microwave devices need very little, so you can reduce the complexity of the system, reducingThe merits of wireless technology(A) WLAN technologyWi-Fi technologies and products are already quite mature, and mass production. The technology for the wireless LAN as an extension of wired

23、networks, broadband applications for the particular location, even though the Wi-Fi technology is widely used, but it is still in the security there is a certain security risk, the Wi-Fi uses a radio frequency (RF ) through the air to send and receive data. Since wireless networks use radio waves to

24、 transmit data signals, are very vulnerable to attacks from outside hackers can easily steal data within the coverage of the waves and even into the unprotected internal LAN.(B) analysis of WiMaxWiMax is a state-of-the-art technology, the introduction of relatively late, there are small frequency re

25、use, the use of the problem of low, but only recently standardized, large-scale promotion of the technology also need to practice the test. From the application prospects of the technology can meet online in a wide range of requirements, coverage can include outdoor and indoor, can be a large area o

26、f coverage, or even a small number of base stations can be achieved throughout the city coverage. WiMax due to its advanced technology and ultra-long transmission distance, has been the industry optimistic about the future direction of development of mobile technologies, and provides excellent last

27、mile Internet access services.(C) of WMN technologyWMN is being studied in the technology, combined with the characteristics of the various technologies continue to study different aspects of integration and not a mature product line to support large-scale application of this technology. The applica

28、tion prospects of WMN in this emerging network not only has a broad application space for wireless broadband access in other areas such as the combination of data, the image acquisition module can monitor or data acquisition of the target object, and is widely applied to detect and other fields. Wit

29、h the other technology is constantly updated sound of WMN better with integration of complementary, so as to be able to exceed and play their respective advantages.(D) 3G technical analysis3G 1996 standards, 2000 to complete the upper-layer protocols, including the complete formulation of standards.

30、 3G network deployment with considerable practical experience, theory of a complete sets of building a network, including network link budget, the model budget and simulation. From the commercial prospects of 3G in some areas has been a large-scale commercial applications, such as many European coun

31、tries, Japan, Korea and so on have been building a 3G network. 3G technology has entered the practical stage, there are many countries and regions are under construction or will be building a 3G network.(5) on LMDS technical analysisLocal Multipoint Distribution business systems, LMDS is a point-to-

32、multipoint fixed broadband wireless access technology, its operating frequency to 20 GHz above, the use of millimeter-wave transmission, within a certain range of digital duplex voice, data, Internet and video services, it is a very good broadband fixed wireless access solutions. In the optimal case

33、, the distance up to 8 km; However, due to rainfall because the distance is usually limited to 1.5 km.Works sector or base station equipment to the ATM backbone network baseband information modulated RF signal transmitted out CPE in its coverage area to receive and RF signal to restore ATM base band

34、 signal, without the need for Each user specifically laying fiber or copper, to achieve bi-directional symmetrical high-bandwidth wireless transmission.(6) MMDS, technical analysisMMDS The main drawback is blocking the signal quality is vulnerable to changes in the weather, the available frequency b

35、and is not wide enough, no more than 200MHz. Second, MMDS is very strict requirements on the transmission path. The modulation technique used by MMDS phase shift keying PSK, (including BPSK, DQPSK, QPSK) and quadrature amplitude modulation QAM modulation technique, and can not do the non-line-of-sig

36、ht transmission is difficult to promote the use of complex urban environment. In addition, MMDS is no uniform international standards, the manufacturers of the equipment compatibility issues.(G) trunking technologyDigital trunking system has many advantages, its spectral efficiency has greatly impro

37、ved, can further improve the user capacity of the cluster system; it increases the ability to signal anti-fading channel, changed for the better quality of wireless transmission; developed digital encryption theory and practical techniques for digital systems, confidentiality, have greatly improved.

38、Digital trunking mobile communication system provides multi-service, that is in addition to the digital voice signal, but also can transmit digital, image information. Transmission within the network is a unified digital signal, therefore greatly improve the service functions of the cluster network.

39、(H) point-to-point microwave technologyThe main advantage of microwave transmission in the following aspects: First, it can reduce the operator's operations. Compared to leased lines, microwave systems, as long as a year or so can be recovered. Second, the microwave transmission system deploymen

40、t simple and fast. Compared with the traditional means of transmission, the advantages of rapid deployment to meet the needs of the development of new business. Third, the current microwave products for the future development is to protect, for new business and new demands of the operators can give

41、good support. The future, the microwave transmission system will be upgraded to all-IP platform, can fully support the future development of the operators.(Ix) satellite communications technologyThe use of satellite with terrestrial communications in some not very densely populated areas. Scattered

42、in these areas, but not intensive users of a wider scope, you can use the satellite as a user connected to the fixed wireline network access facilities. Terrestrial communications network constitutes a broadband multimedia communications network, using the satellite into a broadband satellite access

43、 system is relatively good and realistic program, and reliable.Satellite communications, after all, the construction of the satellite as a communications platform, the ground station, the communication channel rental costs need to spend a lot of money, and communication resources for the satellite c

44、ommunications company, by its bandwidth limit, the transmission of large amounts of data need to pay a very high price. Therefore, as the daily production, the life use is extremely uneconomical; and satellite communications are more suitable as emergency communications, combat communications, overs

45、eas communications.(1)IntroductionFour after the 17th century discovered how to generate electricity with a metal wire transfer of power. Today, for the power grid, power lines around the world every corner. Work and life, more and more electrical appliances brought us great convenience at the same

46、time, knew the power cord of a variety of "disarray" troubled by the data line is also increasing. However, all these years of technological development, the growing popularity of wireless data transmission technology, scientists have a great breakthrough in wireless power transmission (Wi

47、reless Power Transmission WPT), a sense, the wireless power transmission is no longer a fantasy - get rid of the chaos of the power cord has become possible in the future life.(2) the history of the development of wireless power transmissionIn the late 19th century known as "usher in the power

48、era of genius." Mingnigula · Tesla (Nikola Tesla ,1856-1943) made outstanding contributions to electrical and radio technology. 1881 he discovered the rotating magnetic field principle, and for the manufacture of induction motor; the 1888 invention of multi-phase AC transmission and distri

49、bution system; made from 1889-1890 Hz oscillator; 1891 invention of high-frequency transformer (Tesla Coil) are still widely used in radio, TV and other electronic equipment. He has committed to research wireless transmission of signals and the possibility of energy in 1899 without wires using high-

50、frequency current of the motor, but due to low efficiency and the security concerns of wireless power transmission technology breakthrough 1. 1901-1905 years, built in the vicinity of New York's Long Island Wardenclyffe tower, is a complex electromagnetic oscillator, conceived it to be able to p

51、ower transmission to any corner of the world, Tesla use of this tower to achieve the resonance of the Earth and the ionosphere.In May 2001, the French National Centre for Scientific Research 皮格努莱特 microwave wireless transmission of electrical energy to light up the 40m outside a 200W light bulb. Sub

52、sequently, in 2003 built on the island of 10kW experimental microwave transmission equipment, has begun to 2.45GHz frequency close to 1km Grande Basang Village for point-to-point wireless power.In 2005, the City University of Hong Kong Department of Electronic Engineering, Professor Xu Shuyuan succe

53、ssfully developed a wireless battery charging platform ", but its use still want products and charger contacts.In October 2006, Japan exhibited a wireless power transmission system. The output power of this system is 7V, 400mA, send and receive coil spacing is 4mm, the transmission efficiency o

54、f 50% for the phone to fast charge.In June 2007, the Massachusetts Institute of Technology assistant professor of physics the Marin 索尔贾希克 research team within a short distance wireless power transmission. They give a 60 cm diameter coil is energized, and 6 feet (about 1.83 meters) outside the connec

55、tion in another coil 60 watt light bulb lit up. The principle of this Marin called "WiTricity" technology "magnetically coupled resonance.In September 2008, the papers published by the North American Electric Workshop, they have been successful in Nevada Lightning Laboratory 800W powe

56、r with a wireless way of transmission to 5m far distance.In October 2009, Nara, Japan, plug-in hybrid bus wireless charging experiment. Powered coil buried in the concrete charge, the car onto the charge, the vehicle coil at the powered coil will be able to start charging.3 the basic principles of w

57、ireless power transmission3.1 of electromagnetic induction - short-range transmissionThe phenomenon of electromagnetic induction is the most significant discoveries in electromagnetism, one of which shows the linkages and transformation between the electric and magnetic phenomena. Electromagnetic in

58、duction is the basic principles of electromagnetism, the transformer is to use the basic principle of electromagnetic induction to work. Magnetic coupling to transfer energy between the basic principles of electromagnetic induction distance power transmission shown in Figure 1, the transmitting coil

59、 L1 and the receiving coil L2. The coil L1 through the alternating current, the current in the surrounding medium, the formation of an alternating magnetic field, the EMF generated in the coil L2 can supply to the mobile device or to charge the battery.3.2 of electromagnetic coupling resonance - medium-range transmissionThe medium-range wireless power transmission is the "radio frequency" electromagnetic wave or non-radiative resonant magnetic coupling "form of power transmission. It is based on electromagnetic resonance c