What is 3G service?

Now "3G communication" is about to become the mantra in people's mouths, so do you know what 3G communication is? The so-called 3G, in fact, is the third generation, which means the third generation digital communication in Chinese. 1995, the first generation of digital mobile phones, can only make voice calls; The second generation digital mobile phones from 1996 to 1997 have added the function of receiving data, such as accepting emails or web pages; The main difference between the third generation and the first two generations is that the speed of transmitting sound and data has increased. It can handle various media forms, such as images, music and video streams, and provide various information services, including web browsing, teleconference and e-commerce. Compared with the first generation of analog mobile phones (1G) and the second generation of GSM, TDMA and other digital mobile phones (2G), [blocking advertisements]

There are many names for 3G communication. ITU defines it as "IMT-2000" (International Mobile Phone 2000), and European telecom giants call it "UMTS" universal mobile telecommunications system. According to the standard, when the mobile terminal moves at vehicle speed, its data transmission rate is 144kbps, the outdoor stationary or walking speed is 384kbps, and the indoor speed is 2Mbps. However, these requirements do not mean that the available rate of users can reach 2Mbps, because the indoor rate will also depend on the detailed frequency planning in the building and the close cooperation between organizations and operators.

The International Telecommunication Union (ITU) has determined three mainstream wireless interface standards for 3G communication, namely W-CDMA (Wideband Code Division Multiple Access), CDMA2000 (Multicarrier Wavelength Division Multiplexing Spread Spectrum Modulation) and TDS-CDMA (time division-synchronous code division multiple access). Among them, the W-CDMA standard mainly originated from the early third-generation wireless research activities in Europe and Japan. The system is used on the existing GSM network and can be easily converted by system providers. The main supporters of this standard are Europe, Japan and South Korea. At the end of last year, at&; T Mobile Services Branch also announced that it has chosen WCDMA as its third generation service platform. CDMA2000 system is mainly proposed by Qualcomm North America Company, and its construction cost is relatively low. Its main supporters include Japan, South Korea and North America. TD-SCDMA standard was first put forward by China, and cooperated with the international community on the basis of RTT. TD-SCDMA standard is completed and becomes a member of CDMA TDD standard. This is a pioneering work in the field of mobile communication in China, and also China's contribution to the development of the third generation mobile communication. In the competition with the 3G standards proposed by Europe and America respectively, TD-SCDMA proposed by China has officially become one of the global 3G standards, which indicates that China has entered a leading position in the field of mobile communication.

3G mobile phone is the product of the integration of communication industry and computer industry. Compared with the previous mobile phone, the difference is too great, so more and more people begin to call this new mobile communication product "personal communication terminal". Even the most layman in the communication industry can easily judge whether a mobile phone is the "third generation" from its appearance: the third generation mobile phones have a large color display screen, which is often touch-sensitive. 3G mobile phone can not only complete high-quality daily communication, but also carry out multimedia communication. Users can write and draw directly on the touch screen of 3G mobile phone and send it to another mobile phone, which may take less than one second. Of course, you can also send this information to the computer or download some information from the computer; Users can use 3G mobile phones to surf the Internet directly, check emails or browse the web. There will be many models of 3G mobile phones with their own cameras, which will allow users to hold computer meetings with their mobile phones and even make digital cameras "redundant".

3G communication is a mobile communication service introduced in the mobile communication market after the first generation of analog technology, and it has been introduced into the agenda in the vigorous development of the second generation digital mobile communication market. With the rise of Internet data services and the improvement of fixed access rate (HDSL, ADSL, VDSL), 3G mobile communication system has also seen the dawn of the market, and attracted more and more attention from telecom operators, communication equipment manufacturers and ordinary users.

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The so-called 3G mobile phone refers to the third generation mobile phone. With the development of technology and economy, mobile phones are no longer the patent of white-collar workers. And there are many kinds and models of mobile phones. From the first generation of analog mobile phones to the second generation of digital mobile phones such as GSM and TDMA, and now to the third generation of mobile phones, mobile phones have become a new generation of mobile communication systems combining voice communication and multimedia communication, and include value-added services such as images, music, web browsing, conference calls and other information services.

Many people first came into contact with 3G mobile phones from a mobile phone advertisement of Nokia. A happy tourist wandered around a strange city with a 3G mobile phone, and the street map displayed in the mobile phone guided him to his destination smoothly. 3G mobile phones have many names. ITU calls it "IMT-2000" and European telecom giants call it "UMTS" (Universal Mobile Telecommunication System). The possible technical standards of 3G mobile phones are WCDMA, CDMA-2000, TD-SCDMA and so on. 3G mobile phone is the product of the integration of communication industry and computer industry. Compared with the previous mobile phone, the difference is too great, so more and more people begin to call this new mobile communication product "personal communication terminal". Even a layman in the communication industry can easily judge whether a mobile phone is the "third generation" from its appearance: most 3G mobile phones have large color display screens, which are often touch-controlled.

The powerful function is based on the extremely high data transmission speed of 3G mobile phones. At present, the transmission speed of GSM mobile communication network is 9.6K kilobytes per second, and the data transmission speed that the third generation mobile phone may eventually reach will be as high as 2 megabytes per second. What supports this point is that Internet technology is fully integrated into 3G mobile phone system, and the most important one is data encapsulation technology. At present, GPRS developed by using data packaging technology on the existing GSM can reach the transmission speed of 384K kilobytes per second, which is equivalent to twice the transmission speed of D-ISDN. 3G mobile phones support high-quality voice, packet data, multimedia services and multi-user rate communication, which will greatly expand the connotation of mobile phone communication.

Want to know what real 3G life is? Your glasses, watches, cosmetic boxes, sports shoes, anything you can see may become a 3G terminal. With the bandwidth and technology available, this multifunctional terminal enables us not only to communicate anytime and anywhere, but also to download and transmit data, pictures and images in both directions. Of course, we can also play online games with strangers we have never met. According to experts, in the 3G era, mobile phones can not only complete voice communication with high quality, but also carry out multimedia communication. Users can write and draw directly on the touch screen of 3G mobile phone and send it to another mobile phone, which may take less than one second. Of course, you can also send this information to the computer or download some information from the computer; Users can use 3G mobile phones to surf the Internet directly, check emails or browse the web. Many models of 3G mobile phones will have their own cameras, which will enable users to use their mobile phones for computer conferences and even make digital cameras "redundant".