4G is the fourth generation mobile communication and technology, referred to, is a 3G and WLAN in one and be able to transmit high quality video images and image transmission quality comparable to high-definition television technology products. 4G system is able to download speed of 100Mbps, 2000 times faster than dial-up Internet access, upload speed can reach 20Mbps, and can meet almost all user requirements for wireless services. The user is most concerned about in terms of price, 4G and fixed broadband networks comparable in price, and billing more flexible, the user can determine based on their needs the services required. In addition, 4G DSL and cable modems in the areas not covered by the deployment, and then extended to the entire region. Obviously, 4G has unparalleled advantages.
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4G development background will be Kazamaki 4G TD-LTE 4G wireless broadband market in China introduced the concept of the main advantages of 4G 1, 2, faster communications, the network wider spectrum of 3, communication 4 more flexible, more intelligent performance 5 compatibility smoother 6, 7, providing value-added services, to achieve a higher quality of Multimedia Communication 8, 9, the frequency with more efficient, cheaper communications costs 5 major 4G technology standard interpretation of cited 2. LTE-Advanced: 3. WiMax: 4. HSPA +: High Speed Downlink Packet Access 5. WirelessMAN-Advanced: 4G defects 1, 2, uniform standard is difficult, technology is difficult to achieve 3, 4, capacity is limited,
chi pink dazzle, the market difficult to digest 5, facilities difficult to update 6, other related problems 4G development prospects 1. a significant difference 2. wireless broadband, a plug-line 3. other markets the world's first 4G commercial country 4G mobile real machine the world's first 4G mobile 4G and the performance of Nokia Siemens Networks open up the world's first formal standard m4G the world's first commercial 4G network (Huawei Participation) 4G latest communications giant, wrestling for the 4G development 1. Huawei Yan Ericsson Doo 2, the world's first commercial LTE. China Mobile Expo The TD-LTE test network 3. 4G standard competition is still fierce 4. LTE is positioned as 3G supplement, not replace Outlook 2010 4G 4G rapid development of communications technology background, to bring a lot of enjoyment. As data communications and multimedia services
needs development, adaptation of mobile data, mobile computing and mobile multimedia operational needs of the fourth generation mobile communications began to rise, it is reasonable to expect that this fourth-generation mobile communication technology gave rise to a better future. All technology can not be achieved overnight, from GSM, GPRS to the 4th generation, need to constantly evolve, and these technologies can coexist. People know that the first mobile phone with the analog cellular communications technology, this technology can only provide a regional voice services, and the effect of poor call performance of confidentiality is not good, the scope of the user's answer is very limited. With the rapid development of mobile phone users has grown rapidly, the traditional modes of communication can not meet the communication needs of the people, in this case appeared in the GSM communication technology, which is narrow with TDMA, allows a radio frequency (ie ' Cellular ') 8 group calls simultaneously. It is determined according to European standards in the frequency range between 900 ~ 1800MHz digital mobile telephone system, a frequency of 1800MHz system also adopted by the United States. GSM is put into use in 1991. The end of 1997, has operations in more than 100 countries, becoming the de facto standard in Europe and Asia. GSM digital network also has a strong confidentiality and anti-interference, clear sound quality, call stable, and have large capacity, high utilization of frequency resources, open interfaces, powerful, and so on. But it can provide data transfer rate is 9.6kbit / s, and five or six years ago with a fixed telephone dial-up speed quite at a time when the internet is almost text-only information. And nowadays is a popular digital mobile communication handset is a second generation (2G), generally use the GSM or CDMA technology. In addition to providing second-generation mobile phone so-called Although in theory, 2G mobile phone users worldwide mobile communications can be carried out, but because there is no uniform international standards, a variety of mobile communication systems are not compatible with each other, to the mobile phone users inconvenience. The defects for GSM communication, people in 2000, launched a new communications technologies GPRS, GSM, the technology is based on a transitional technology. GPRS in the GSM launch marked the history of the development has taken a most significant step, GPRS mobile data network between the user and provide a connection to the mobile users with high-speed wireless IP and X.25 packet data access service . After that, communication operators have to introduce EDGE technology, this communication between the existing technology is a second-generation mobile networks and third generation mobile networks the transition between the technology, so some people call it half EDGE from GPRS to provide a third generation mobile communication transitional program, so that the existing network operators to make maximum use of existing wireless network equipment, third-generation mobile network in advance of commercialization to provide users with personalized multimedia communication services. In the emerging communication technology continues to drive under the sign of a symbol of technology WCDMA 3G communication may become the future mainstream of communications technology. The technology can provide users with the highest 2Mbit / s data transfer rate, in such conditions, the application of the computer can be any media to pass easily through the wireless network. WCDMA through the effective use of broadband, not only to smooth the process sounds, images, data, and Internet speed connection; addition WCDMA and the combination of MPEG-4 technology can solve real dynamic image. The bottleneck of communication between people by the network transmission rate of change in the provision of a variety of new applications: how to make the wireless network to better services for people not to bring harassment, how to get everyone quickly from the sea of information to get the information they need, how can conveniently carry, using a variety of terminal equipment, terminal devices to automatically work together better and so on. On the basis of the communication technology, wireless communication technology may eventually move towards 4G communication technology era. Wireless communication systems from the development process point of view, the first generation of mobile communication system tasks have been achieved, but at this stage is the second-generation mobile communication system of the times, over the next decade will be the 3G mobile communication system is hing period, perhaps to a dozen years later is the fourth generation mobile communications world. But it is not difficult to find each of the different mobile communication systems are the point in time there will be repeated about every ten years there is a technical update, but with the communication of technology, perhaps the change will be faster, the time will be shorter . For the mobile communication service providers, systems equipment supplier, or other related industries, it must always pay attention to changes in mobile communication technology to meet market demand. 4G TD-LTE will be the wireless broadband market in China due Kazamaki Long Term Evolution Long-Term Evolution (LTE) and WiMax in the global telecommunications industry, to vigorously promote, the former (LTE) is the most powerful leading 4G mobile communication technology, is a meteoric rise, quickly occupation of the Chinese market. While Qualcomm and Yota TD-LTE two companies is not yet mature, but many companies home and abroad have turned to wireless carriers TD-LTE. IBM data show that 67% of operators are considering the use of LTE, as this is their main source of future market. IBM also confirmed the news of this statement. While only 8% of the operators consider the use of WiMAX. While WiMax can give its customers the fastest speeds available on the market network, but still not rival technology LTE. TD-LTE is the first 4G wireless mobile broadband network data standards, the China's largest telecom operators - China Mobile, revised and published. After conducting a series of field trials, expected in the next 2 years into the commercial phase. Ulf Ewaldsson, vice president of Ericsson, said: Among, the higher the technology has been developed in the laboratory. Therefore, people look forward to the third generation mobile communication systems, while services brought about by the fourth generation mobile communication system of the latest technology are among the lab quietly. So in the end what is 4G communications it? Up to 2009 people still can not precisely define the 4G communications, some say the concept of 4G communications services from other wireless technologies, from wireless application protocol, the global mini wireless services to 3G; some say is a 4G communication beyond 2010 research on topics other than, 4G communication system is the system can use a variety of wireless technologies; but no matter how people define the 4G communications, one thing is certain is that people are able to 4G communication may be a more perfect than the 3G communications The new wireless world, it can be hard to imagine many consumers to create the application. 4G maximum data transfer rate of more than 100Mbit / s, the rate of mobile phone data transfer rate of 1 million times, is also a 3G mobile phone rate 50 times. 4G mobile convergence can provide high-performance media content and applications through the ID as personal identification devices. It can also accept high-definition movies and TV shows to the combined broadcast and communications infrastructure, a new link. In addition, 4G wireless real-time connection cost of certain services such as cheaper than 3G. There, 4G is expected to integrate different modes of wireless communications - from indoor wireless LANs and Bluetooth networks, cellular signals, radio and television to satellite communications, mobile users can roam freely from one standard to another standard. 4G communications technology is not out of the previous communication technologies, but the traditional communication technology, and use a number of new communication technologies to continuously improve the efficiency of wireless communication networks and functions. If 3G can provide people with a high-speed transmission of wireless communication environment, then the 4G communication is an ultra high-speed wireless network,
chi iron, a cable does not need the information super highway, this new network allows phone users to wireless and three-dimensional virtual reality connection. Compared with the traditional communication technologies, 4G communication technology is the most obvious advantage of call quality and data communication speed. However, call quality, the mobile phone consumers is acceptable. With the technology development and application of existing mobile telephone networks in the mobile phone call quality is also improved. High-speed data communication speed is indeed a big advantage, its maximum data transfer rate up to 100Mbit / s, is simply unthinkable. In addition, as technology advanced to ensure that significantly reduce the cost of investment, the future 4G communication costs are lower than the communication costs in 2009. 4G communications technology is once again following the third generation of the future evolution of wireless communication technology, the development of a more have clear objectives: to improve the mobile device speed wireless Internet access - According to 3G market to go three-phase development plan, 3G's multimedia services in 10 years to enter the third stage of development, this time global coverage of the 3G network has been basically completed, the global population of more than 25% of third generation mobile communication systems. In developed countries, 3G services, the penetration rate of more than 60%, then the need for more time to a new generation of systems to further improve service quality. To take full advantage of 4G communications to bring advanced services, one must also use a variety of 4G terminals can be achieved, and many telecommunications operators see the future of communications is huge market potential, they have begun to look aimed at to the production of 4G communication terminal products, such as production of small high-speed packet communication terminal, corresponding with the production of video telephony camera and film and television transmission services, video terminal, or the production of computer data communication card that matches the special terminal. With these communication terminal, people can be arbitrary mobile phone users to roam, and anytime, anywhere to enjoy high-quality communications. 4G network architecture and key technology 4G mobile network architecture can be divided into three layers: the physical network layer, middle layer of the environment, the application network layer. Provide access to the physical network layer and routing functions, which by a combination of radio and core network to complete the format. Intermediate environment layer QoS mapping functions, address change and complete management. Physical network layer and the middle layer and its environment, the interface between the application environment is open, it makes the development and delivery of new applications and services easier to provide seamless high data rate wireless service, and run on multiple band. This service can be adaptive multiple wireless standards and ability to multi-mode terminal, across multiple operators and services, providing a wide range of services. The fourth generation mobile communication system including channel key technology transfer; strong anti-interference, high-speed access technology, modulation and information transmission technology; high-performance, miniaturization and low-cost adaptive array smart antennas; high-capacity, low-cost wireless interface and optical interface; system management resources; software radio, network infrastructure agreements. The fourth generation mobile communication system is mainly based on orthogonal frequency division multiplexing (OFDM) as a core technology. OFDM technology is characterized by highly scalable network structure, with good noise immunity and resistance to multi-channel interference, can provide higher-quality wireless data technology (high speed, small delay) service and better cost performance, 4G wireless networks can provide a better solution. For example, wireless local loop (WLL), Digital Audio Broadcasting (DAB), etc., are expected to use OFDM technology. 4G mobile communications to accelerate the growth of wide band wireless connectivity to provide the technical response to the request of the public and private crossing, and a variety of indoor and outdoor wireless systems and networks to ensure seamless service. On the most appropriate available network needs to provide users the best services, Internet-based communications can meet the expected growth, add new bands, so that a large expansion of spectrum resources, providing different types of communication interfaces, the use of technology-based routing network architecture to the development of Fourier transform to the fourth generation of the hardware architecture for network architecture. To the data of mobile communication, high speed, broadband, high frequency direction of development, mobile data, mobile IP mobile networks is expected to become the mainstream of business. If the main advantages of 4G 2G, 3G communication of information for human development is negligible, then the future of 4G communications gave the people the real freedom of communication, and completely changed the way people live and even social patterns. Conceived in 2009 in the 4G communication has the following characteristics: 1, faster communication of 4G communications as people first purpose is to enhance the cellular phones and other mobile devices and wireless Internet access rate, the 4G communication of the most impressive It features a faster than the speed of wireless communications. From the data rate mobile communication system for comparison, the first generation of analog voice services only; second generation digital mobile communication system transmission rate is only 9.6Kbps, up to 32Kbps, such as PHS; and the third generation mobile communication system data transfer rates up to 2Mbps; experts estimate, the fourth generation mobile communication system can achieve 10Mbps to 20Mbps, or even up to 100Mbps per second maximum speed can transmit wireless information, this speed is equivalent to 2009, the latest transmission speed of a mobile phone times or so. 2, the network in order to enable a wider spectrum to 100Mbps transmission of 4G communications, telecommunications operators must be based on the 3G communication network to carry out substantial rehabilitation and research in order to make 4G network communication bandwidth than 3G cellular system network much higher bandwidth. According to research 4G Communications, AT & T executives say the channel is estimated that each may possess 100MHz 4G spectrum, the equivalent of W-CDMA 3G network 20 times. 3, communication is more flexible in the strict sense, 4G cell phone features, has not simply classified as is a small computer on it, and 4G mobile phones from the appearance and style, there will be even more amazing breakthroughs, it is conceivable that, eyewear, watches, cosmetic case, travel shoes, to facilitate and personality as a precondition for any one items are likely to see a 4G terminal, but people should still do not know how they call it. Future 4G communication so that people can not only communicate anytime, anywhere, but you can download the two-way transmission of information, pictures, images, and of course you can, and never met a stranger online on-line sparring game. Online positioning system may have been nowhere to hide the anguish never locked, but the map with it accordingly provides the convenience and security compared to the almost negligible. 4, the fourth generation intelligent high performance mobile communications more intelligent, not only in the 4G communication terminal equipment with intelligent design and operation, such as menus and scroll operations would greatly reduce dependence on more important 4G phone functions can be achieved in many imagine. Such as 4G mobile phone according to the environment, time and other factors set to timely reminder at this time of the phone's owner does, or should not do, 4G mobile movie tickets information can be directly downloaded to the PDA above These data can be the ticket sales, seat availability display very clear, we can use the information to the satisfaction of online movie ticket purchase their own; 4G mobile phones can be seen as a portable TV for watching sports events and the like all live. 5, compatibility make the 4G communication smoother been accepted as quickly as possible, not only considering its powerful, but also should take into account the basis of the existing communications to allow more investment in existing communications users in the case of at least will be able to easily transition to 4G communications. Therefore, from this perspective, the future fourth generation mobile communication system should have a global roaming, open interfaces trophies with a variety of network connectivity, end-diversity and a smooth transition from second generation and so on. 6, provide a variety of value-added services from 3G 4G communication is not based on communication through the simple upgrade and evolution, their core technology is simply a different building, 3G CDMA mobile communication system is mainly based on core technologies, and 4G Mobile Communication System Zeyi orthogonal frequency division multi-task technique (OFDM) the most attention, the use of this technology such as wireless local area that people can loop (WLL), Digital Audio Broadcasting (DAB) and other aspects of the proliferation of wireless communications services; But taking into account the transitional 3G communications, the fourth generation mobile communication system will not only use OFDM in the future just a technology, CDMA technology in the fourth generation mobile communication systems, and OFDM technologies complement each other in order to play a greater role, and even the future fourth generation mobile communication system will also integrate new technologies such as OFDM / CDMA production, previously mentioned digital audio broadcasting, in fact, the use of technology is it really OFDM / FDMA integration technology, the same Using a combination of two technologies. Therefore, in future OFDM as the core technology to the fourth generation mobile communication systems, will combine the advantages of two technologies, part of the extension will be based on CDMA technology. 7, to achieve a higher quality of Multimedia Communication Although the third generation mobile communication system can achieve a variety of multimedia communications, but future 4G communication to meet the third generation mobile communication still can not achieve coverage, communication quality, cost, high-speed support high-resolution data and multimedia service needs, the fourth generation mobile communication system provides wireless multimedia communication services including voice, data, video and other large amounts of information transmitted through the channel out of broadband, for future fourth generation mobile communication systems referred to as Not just for fourth generation mobile communication applications due to the increase in number of households, more importantly, we must demand in response to the transmission of multimedia, of course, communication quality requirements. In conclusion, first of all must be able to accommodate a large number of users in the market, improve the existing communication quality is poor, and to achieve high-speed data transmission requirements. 8, the frequency of use of more efficient compared to the third generation mobile communication technology, the fourth generation mobile communication technology used in the development process in the development and introduction of many powerful breakthrough technology, for example, fiber optic communications products company in order to further enhance the wireless Internet bandwidth is the width of the trunk, the introduction of the exchange-level technology, this technology can also cover different types of communication interfaces, that is mainly the use of fourth-generation routing technology (Routing)-based network architecture. The use of several different technologies, so the use of radio frequency than the second and third generation systems much more effective. Estimated according to the most optimistic scenario, this effectiveness can make more people use the same amount of radio spectrum to do more things, and do these things quite fast. The researchers said could reach download speeds of 5Mbps to 10Mbps. 9, cheaper communications costs not only solve the 4G communication compatibility issues with the 3G communication, so that more of the existing communication users can easily upgrade to 4G communications, and 4G communication introduces a number of cutting-edge communications technologies that ensure the 4G communications can provide a very high flexibility of system operation, it is relative to other technology, 4G communication is easy to deploy much more rapidly; while 4G communications networks in building systems, communications providers are considered directly in 3G communication network infrastructure on top, with the gradual introduction of the method, so it can effectively reduce the cost of running and users. According to the researchers claim, 4G wireless communications such as real-time connection cost of some services cheaper than 3G communications. Interpretation of 5 major 4G technology standard introduced the International Telecommunication Union (ITU) has WiMax, HSPA +, LTE 4G formally incorporated into the standard, the addition has been determined before the LTE-Advanced, and WirelessMAN-Advanced two standards, the current 4G standards have been reached the 5. 1. LTE: LTE (Long Term Evolution, LTE) LTE: LTE (Long Term Evolution, long term evolution) is the 3G evolution of the project, which improve and enhance air access to 3G technology, using OFDM and MIMO for its wireless network Evolution of the sole criterion. Main feature is the 20MHz downlink spectrum bandwidth can provide 100Mbit / s and uplink 50Mbit / s peak rate, relative to the 3G network has the capacity to improve the area, while significantly reducing the network delay: propagation delay less than the internal one-way 5ms, the control plane from sleep to active state transition time is less than 50ms, from the state to the active presence of the migration time of less than 100ms. And this standard is 3GPP Long Term Evolution (LTE) project, 3GPP started the last two years the biggest new technology research and development projects, the history of its evolution as follows: GSM -> GPRS -> EDGE -> WCDMA- -> HSDPA/HSUPA--> HSDPA + / HSUPA + -> LTE Long Term Evolution GSM: 9K -> GPRS: 42K -> EDGE: 172K -> WCDMA: 364k -> HSDPA / HSUPA: 14.4M -> HSDPA + / HSUPA +: 42M -> LTE: 300M because the current version of WCDMA network upgrade to HSPA and HSPA + are to LTE evolution of this state, including China's own TD-SCDMA networks will also be bypass the HSPA evolution directly to LTE, so the 4G standard to get maximum support, will be the future 4G standard mainstream. The network provides speeds comparable to fixed broadband and mobile network switching speed, network browsing speed greatly enhanced. 2. LTE-Advanced: LTE-Advanced: literally, LTE-Advanced is an upgraded version of LTE technology, then why are two standards to be the 4G standard? LTE-Advanced, formally known as Further Advancements for E-UTRA, which meet the ITU-R for IMT-Advanced technology needs of assembly is the formation of the European 3GPP proposal for IMT-Advanced technology is an important source. LTE-Advanced is a backward-compatible technology, fully compatible with LTE, is evolution rather than revolution, this is equivalent to the relationship between HSPA and WCDMA. LTE-Advanced related characteristics are as follows: Bandwidth: 100MHz peak rate: Downstream 1Gbps, 500Mbps peak uplink spectrum efficiency: down 30bps/Hz, uplink 15bps/Hz optimized for the indoor environment to effectively support high-bandwidth applications of new frequency bands and a substantial increase in peak rate, Improved spectral efficiency limited strictly speaking if, LTE as a 3.9G mobile Internet technology, then the 4G standard LTE-Advanced as a more precise number. LTE-Advanced in the finalists, including TDD and FDD both formats, including TD-SCDMA standard will be able to evolve to the TDD, and FDD WCDMA network can evolve to the standard. TD-SCDMA mobile led directly to bypass the network expects to HSPA + network and direct access to the LTE. 3. WiMax: WiMax: WiMax (Worldwide Interoperability for Microwave Access), the global microwave Internet access, WiMAX is another name for IEEE 802.16. Starting point for high technology WiMAX,
chi pink dazzle hair straightener, WiMax can provide maximum access speed is 70M, the speed of 3G can provide 30 times the speed of broadband. Wireless networks, it is indeed a remarkable progress. The progressive realization of WiMAX broadband services mobile, and 3G mobile services is broadband to achieve the two networks will be increasingly high level of integration, which is the world's future mobile and fixed network convergence. 802.16 is used in the work of unlicensed spectrum bands in the range between 2GHz to 66GHz, while the use of 802.16a is a 2G to 11GHz unlicensed band broadband wireless access system, the channel bandwidth according to demand in the 1.5M 20MHz range adjustment, currently has more seamlessly switch high-speed mobile technology is developing IEEE 802.16m. Therefore, the 802.16 spectrum to use than any other wireless technology may be more abundant, WiMax has the following advantages: (1) for known interference, narrow channel bandwidth is conducive to avoid interference, but also help save the spectrum. (2) flexibility to adjust the bandwidth capacity that will benefit operators or users coordinate spectrum. (3) WiMax can achieve 50 km distance of the wireless signal transmission can not match the wireless LAN, 3G network coverage area is 10 times the towers, as long as the construction of a small number of base stations covering the whole city can be achieved, enabling wireless network coverage greatly enhanced. But WiMax network in network coverage and network bandwidth on a huge advantage, but its mobility, but has a congenital defect, can not meet the high-speed (50km / h) under the seamless network, in this sense, WiMax is also 3G networks can not reach the level, strictly speaking, can not be counted as mobile communication technology, but only wireless LAN technology. But hope lies in IEEE 802.11m WiMax technology, will be able to effectively solve these problems, it is precisely because of China Mobile, Intel, Sprint active participation of major manufacturers, WiMax LTE as the 4G network voice phone after . IEEE 802.16m on this technology, we will remain in the final for the detail. 4. HSPA +: High Speed Downlink Packet Access HSPA +: High Speed Downlink Packet Access (High Speed Downlink Packet Access), while HSUPA is the high-speed uplink packet access technology, which together referred to as HSPA technology , HSPA + is a derivative version of HSPA, HSPA network can be transformed and upgraded to the network, is an economic and efficient 4G network. We can also learn from the above, HSPA + LTE line with the long-term evolution of norms, standards and network as 4G 4G network while the other exists, it is very beneficial to the current WCDMA networks worldwide and HSPA network upgrade and over, cost advantages are obvious. Contrast HSPA network, HSPA + in the throughput by about 12.58% indoor and outdoor area to improve throughput of about 32.4%, to adapt to high-speed network based data processing, will be the 4G standard short-term ideal. China Unicom has been working on the current relevant planning, T-Mobile also launched the 4G network, but due to ITU 4G standards has not been fully determined,
CHI Pink Dazzle Flat Iron, so the action is not great. 5. WirelessMAN-Advanced: WirelessMAN-Advanced: WirelessMAN-Advanced is in fact an upgraded version of WiMax, the IEEE 802.11m standard, IEEE 802.16 series of standards formally known as WirelessMAN, the WirelessMAN-Advanced is extremely IEEE 802.16m. Which, 802.16m highest offer 1Gbps wireless transmission rate, also compatible with the future 4G wireless networks. 802.16m in the The standard also supports the The advantages are as follows: 1, to improve network coverage, rebuilding the link budget; 2, spectrum efficiency; 3, to improve data and VOIP capacity; 4, low latency & QoS enhancement; 5, power savings; current WirelessMAN-Advanced There are 5 network data specifications, including the very low rate of 16kbps, the low data rate data and low-speed multimedia 144kbps, medium-speed multimedia to 2Mbps, 30Mbps high-speed multimedia to high-speed multi-media can reach 30Mbps - 1Gbps. But the standard may be the first to be used by the military, IEEE said the military aspects of the intervention will be able to make WirelessMAN-Advanced faster maturity and perfection, and the military today is the civil tomorrow. In any case, WirelessMAN-Advanced been recognized by ITU and become a great possibility of 4G standards. 4G defects for the people, the future 4G communication does seem very mysterious, and many people think that the fourth-generation wireless communication network system is the invention of human history, the most complex technical system, indeed the fourth generation of wireless communication networks specific implementation of the process a large number of technical problems headaches,
CHI Turbo Ceramic Flat Iron, probably does not make people feel that accidents and strange, the fourth-generation wireless communication networks and more technical problems and Internet-related, and it takes several years to resolve . In general, to smooth and comprehensive implementation of 4G communications, you may encounter the following difficulties: 1, although the standard is difficult to unified theory, 3G mobile phone users worldwide mobile communications can be carried out, but because there is no uniform international standards, a variety of mobile communication systems are not compatible with each other to give cell phone users inconvenience. Therefore, the development of fourth generation mobile communication system must first address the need for global communication standard such as a standardized problem, and will be the world's major communications companies have been debating this. 2, the future of technology is difficult to achieve despite the 4G communication can bring a better tomorrow, but do not expect to be able to use this technology right away, some still need 5 years or so the technology can be published. According to the research of this technology developers, to achieve download speeds of 4G communications still faces a number of technical problems. For example, how to ensure that floor areas, mountains, and other obstructions and other vulnerable areas of the signal strength and other issues. Japan's DoCoMo, said that in order to solve this problem, the company will have different coding techniques and transmission technology to be tested. Also in the transfer of technical problems that exist in so easily from a mobile phone base station coverage area to another when the base station and the network coverage area lost contact. As the fourth generation wireless communication network architecture is a complex issue is particularly prominent. However,
chi pink dazzle limited edition, industry experts said they believe this problem can be resolved, but will take some time. 3, capacity is limited about the future of 4G communications most impressive transfer rate of communication than it will be greatly enhanced, in theory, the so-called broadband speed 100MB per second, compared with 2009, the latest mobile phone information transmission speed 10KB per second, 10,000 times faster, but the speed of mobile phone communication system capacity will be limited, such as system capacity is limited, the more mobile phone users, the slower. According to expert analysis, 4G phones will be difficult to achieve the theoretical speed. If you do not increase the speed, 4G phones will be greatly reduced. 4 Some experts predict the market is difficult to digest after 10 years, the third generation multimedia mobile communication services will enter the third stage of development, this time global coverage of the 3G network has been basically completed, the global population of more than 25% of third generation mobile communication systems , the third generation technology is still in the slow market, then the industry is absorbing a third-generation technologies, for the fourth generation mobile communication systems also need to accept a gradual transition process. In addition, the transition process, if the 4G communication system or the terminal because of the shortage causes delays, then known as the 5G technology at any time could threaten the profitability of 4G plans, at this time 4G long investment recovery and profit plans will become Abnormal fragile. 5, the facility is difficult to update the system before deploying 4G communications network covering most of the global wireless infrastructure is based on established third-generation mobile communication system, and if the transfer to the fourth generation of communications technology, then many of the global wireless infrastructure have to go through a lot of changes and updates, this is bound to change and update a comprehensive mitigation 4G communications market, the occupation rate of the market. And then, it must require to upgrade to 3G communication terminal capable of supporting higher speed data transmission and communication of the data services, 4G 4G terminal, that is 4G 4G communication terminal to be able to provide timely communication network is completed, can not let production lags behind communication terminal network construction. But according to some of the facts, in the 4G communication technologies into the business of a comprehensive two three years after the date, consumers can be expected to spend the stable performance of 4G mobile communications. 6, other difficulties because of more powerful mobile phones, and wireless communications networks become more complex, the same function of increasing number of 4G communications in the same time, its construction and development will encounter more than the previous system construction many difficulties and troubles.
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