Free sports events uefa champions league app android

List of contents of this article:

• 1,Achievements at different stages of modern mobile communication technology in China
• 2,The Evolution and Development of Mobile Communication Technology
• 3、 What are the characteristics of each stage of development from 2G to 5G?
• 4, 5, What does GSM mean

Achievements at different stages of the development of modern mobile communication technology in China

The development of mobile communication technology has gone through three stages: the first generation of mobile communication system: In the late 1970s, AT&T in the United States developed the first set of cellular mobile phone systems; the second-generation mobile communication system: the second-generation mobile communication digital wireless standards include: GSM; D-AMPS; PDC and IS-95CDMA, etc.

Looking at the development process of mobile communication, contemporary mobile communication can be divided into three stages: (1) The first generation of mobile communication is based on analog FM and frequency division multi-address technology, including public mobile communication system represented by cellular network system, dedicated mobile communication system represented by cluster system and no Rope phone.

Five remarkable achievements have been made in the construction of digital China in the new era: digital infrastructure has achieved leapfrog development.

The evolution and development of mobile communication technology

1. Judging from the development process of mobile communication, mobile communication basically needs to be upgraded every 10 years. The first generation of mobile communication technology began in the 1980s, a cellular wireless telephone system based on analog technology. The 1G wireless system is designed to transmit only voice traffic and receive network traffic restrictions.

2. Its development history can be divided into the following stages: 2002-2005: At the beginning of its establishment, it mainly provided fixed telephone, broadband and other services.2006-2010: Began to lay out the 3G network and launched a number of value-added services, such as mobile payment, mobile TV, etc.

3. From 1G to 5G refers to the renewal of mobile communication technology, and the upcoming 5G is the fifth generation.

What are the characteristics of each stage of development from 2G to 5G?

1. Specifically, each generation of communication technology is different in many places, but the biggest difference is the difference in speed.

2. G presents the characteristics of low delay, high reliability and low power consumption. It is no longer a single wireless access technology, but a general term for the solution after the integration of a variety of new wireless access technologies and existing wireless access technologies (4G backward evolution technology).

3. G period, that is, GPRS (General Packet Radio Service) general packet wireless service period. At this time, there is a data Internet service. With the PS core network, that is, Packet Switch, packet switching/packet switching. Packet switching no longer occupies the channel, but sends packets one after another.

Switching technology in the second-generation cellular system

The more typical systems of the second-generation cellular mobile communication are GSM, D-AMPS (ADC or IS-136), PDC (JDC ) and CDMA (IS-95). Except for CDMA (IS-95) The system uses CDMA technology to distinguish different physical channels, and other systems use TDMA technology to distinguish different physical channels.

Because the mobile communication system adopts a cellular structure, the mobile station must switch across the area when crossing the spatially divided community. That is, complete the transfer of the air interface from the mobile station to the base station and the corresponding transfer of the base station to the network population and the network population to the switching center.

This system consists of a mobile service switching center (MSC), a base station (BS) equipment and a mobile station (MS) (user device) and a transmission line from the switching center to the base station, as shown in the figure below.

Allowing to switch cellular data means allowing the switching of mobile data traffic.

What does GSM mean

1. The meaning of GSM GlobalSystem for Mobile Communications, that is, GSM, also known as Pan-European digital mobile phone system, It is the most widely used mobile phone standard at present. More than 1 billion people in more than 200 countries and regions around the world are using GSM phones.

2. The Global Mobile Communication System, abbreviated as GSM, is a digital mobile communication standard formulated by ETSI, the European Telecommunication Standards Organization. Its air interface adopts time-time multi-address technology. Since it was put into commercial use in the mid-1990s, it has been adopted by more than 100 countries around the world.

3. GSM is what we commonly call 2G network, not 3G network. 3G network can be backward compatible with 2G network.