Communication technology advances to bring a lot of enjoyment. With the demand for data communications and the development of multimedia services to meet the 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 can bring better the 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 mode 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 by 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 one hundred nations, becoming the de facto same old in Europe and Asia. GSM digital community also has a strong confidentiality and anti-interference, clear sound high quality, name strong, and have huge capacity, top utilization of frequency resources, open interfaces, tough, 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 “Global” voice business, has been to provide low-speed data services, and that is received Send PM and the like. Although in conception, 2G cell phone users world wide cellular communications can be performed, but as a result of there is no uniform world standards, a variety of cell communique programs aren\’t appropriate with each and every 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 need to introduce side generation, this verbal exchange between the existing era is a second-era mobile communitys and third generation cell networks the transition between the technology, so a few other folks name it “II part “technology, which effectively stepped forward the efficiency of channel coding GPRS high-speed mobile knowledge usual that allows information transfer charges of up to 384KbPs, can absolutely meet the long run needs of wireless bandwidth for multimedia packages. edge from GPRS to offer a 3rd era mobile communique transitional program, in order that the existing community operators to make most use of current wireless community equipment, third-technology mobile network upfront of commercialization to supply customers with customized multimedia verbal exchange services and products.
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 efficient use of broadband, no longer handiest to smooth the process sounds, images, information, and internet speed connection; addition WCDMA and the combo of MPEG-4 era can solve real dynamic symbol.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 seek out every of the other mobile verbal exchange systems are the point in time there will be repeated about each ten years there is a technical update, however with the conversation of technology, in all probability the modification can be faster, the time can 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.