Excuse me, teacher, what is a 3D mobile phone?

It’s a 3G mobile phone.

Now "3G communication" is about to become a mantra on people's lips, so do you know what 3G communication is? The so-called 3G, in fact, its full name is 3rd Generation, and its Chinese meaning refers to the third generation of digital communications. The first generation of digital mobile phones that came out in 1995 could only make voice calls; the second generation of digital mobile phones that appeared from 1996 to 1997 added the function of receiving data, such as receiving emails or web pages; the third generation and the first two generations of mobile phones The main difference is the improvement in the speed of transmitting voice and data. It can handle various media forms such as images, music, and video streams, and provide a variety of information services including web browsing, conference calls, e-commerce, etc. Compared with the first generation of analog mobile phones (1G) and the second generation of digital mobile phones (2G) such as GSM and TDMA, 3G communications have many names. The ITU stipulates that it is "IMT-2000" (International Mobile Communications). 2000) standard, European telecommunications giants call it "UMTS" Universal Mobile Telecommunications System. The standard stipulates that when a mobile terminal is moving at vehicle speed, its transmission data rate is 144kbps, when it is stationary or walking outdoors, the data rate is 384kbps, and when indoors it is 2Mbps. But these requirements do not mean that the user-available speed can reach 2Mbps, because the indoor speed will also depend on the detailed frequency planning in the building and the close cooperation between the organization and the operator.

The International Telecommunications Union (ITU) has determined that the three mainstream wireless interface standards for 3G communications are W-CDMA (Wideband Code Division Multiple Access), CDMA2000 (Multi-Carrier 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 transitioned for system providers. The main supporter of the standard There are Europe, Japan, and Korea. At the end of last year, the AT&T mobile business branch in the United States also announced that it would select WCDMA as its third-generation business platform. The CDMA2000 system is mainly proposed by Qualcomm North America. Its construction cost is relatively low. Its main supporters include Japan, South Korea, North America and other regions and countries. The TD-SCDMA standard was first proposed by China and based on this wireless transmission technology (RTT), it cooperated with international cooperation to complete the TD-SCDMA standard and became a member of the CDMA TDD standard. This is the first step in the Chinese mobile communications industry. A pioneering undertaking, it is also China’s contribution to the development of third-generation mobile communications. In competition with the 3G standards proposed by Europe and the United States, the TD-SCDMA proposed by China has officially become one of the global 3G standards, which marks that China has entered the world's leading position in the field of mobile communications.

3G mobile phones are completely the product of the integration of the communications industry and the computer industry. Compared with previous mobile phones, the difference is really huge, so more and more people are beginning to call this type of new mobile communication products It is a "personal communication terminal". Even the most layman in the communications industry can easily tell whether a mobile phone is a "third generation" based on its appearance: third-generation mobile phones have a large color display screen, which is often touch-sensitive. In addition to completing high-quality daily communications, 3G mobile phones can also perform multimedia communications. Users can write and draw directly on the touch display of a 3G mobile phone and transfer it to another mobile phone, and the time required may be less than a second. Of course, this information can also be transferred to a computer, or certain information can be downloaded from a computer; users can use 3G mobile phones to directly access the Internet, check emails or browse the web; there will be many models of 3G mobile phones with built-in cameras. It will allow users to use mobile phones for computer meetings and even make digital cameras "redundant".

3G communication is a mobile communication market that has experienced the introduction of the first-generation analog technology mobile communication services, and was introduced into the agenda during the booming development of the second-generation digital mobile communication market.

As Internet data services continue to heat up and fixed access rates (HDSL, ADSL, VDSL) continue to increase, 3G mobile communication systems have also seen the dawn of the market and are becoming increasingly important to telecom operators, communication equipment manufacturers and ordinary people. users are concerned about.

In 2006, 3G will be officially launched and put into trial operation in China. For relevant information, please refer to Beiqing.com information at www.msn.com