What is 2G communication?

What is 2G?

The "G" in 2G stands for Generation, and 2G refers to the second generation of wireless communication technology. Digital services began in 1993, replacing the analogue systems that had been used up until then.
In terms of services, with the realization of communication using packet switching technology in 2G, data communication services began in earnest in addition to voice call transmission, and Internet connection services for mobile phones were provided.
From a technical standpoint, the adoption of digital methods has made it possible to encode and compress data, significantly reducing the bandwidth required.

Initially, 2G was criticized for being expensive and having inferior communication speeds and quality compared to other mobile communication systems that existed at the time, such as pagers and PHS, but these issues were improved through various institutional reforms and technological innovations. As a result, the number of mobile phone subscribers increased significantly, and mobile phone services became widely used and established as a communication infrastructure throughout the world.

What are the wireless communication methods for each generation?

The features of 1G to 5G are as follows:

• 1G
  A communications standard for transmitting voice in an analog format. In Japan, it was adopted for car phones released by Nippon Telegraph and Telephone Public Corporation in December 1979, and for shoulder-mounted mobile phones in 1985. Because it was an analog format, there was a high risk of noise and eavesdropping.
• 2G
  A digital communications standard that emerged in 1993. As wireless technology became digital, data communications via mobile phones became widespread, allowing users to use email and the internet on their mobile phones.
• 3G
  A communications standard that complies with international standards. Up until 2G, technology development was carried out separately in various parts of the world, meaning that one mobile phone could not be used worldwide. To solve this problem, 3G was introduced as a communications standard that complies with international standards. The CDMA system increased the number of devices that could be connected, and it also became possible to use cameras, still image streaming, and browsers on mobile phones. It is also now used for wireless communication in IoT devices.
• 4G
  A communications standard with even faster communication speeds. With the expansion of transmission capacity through technologies such as MIMO, it has become possible to easily enjoy large-volume content such as video streaming services, smartphone games, and music streaming on mobile phones and smartphones. In addition, VoLTE service has been launched as a way to convert voice calls to IP.
• 5G
  This communication standard features ultra-high speeds, ultra-low latency, and multiple simultaneous connections. It is expanding its scope of use in a variety of services and industries, enabling the transmission of 4K/8K high-definition video and immersive video using AR/VR, as well as autonomous driving support and remote medical care.

What is 2G communication in Japan?

In Japan, there were two types of systems: the PDC (Personal Digital Cellular) system, which is unique to Japan, and cdmaOne, which is the American IS-95 system.
First, the PDC system developed by NTT in 1993 was adopted by NTT DoCoMo, and in 1994 the Cellular Group, IDO (Japan Mobile Telecommunications Co., Ltd.) and Digital Phone Group each began offering services using the PDC system.
Subsequently, from 1998, Cellular Group and IDO adopted cdmaOne, a technology that was ahead of the next generation (3G), resulting in the coexistence of different technology systems within the country.

Current 2G communication situation in Japan

In Japan, 2G service ended in 2012.

Related columns:

• 2G Communications in Japan (Technical Column)

What is 2G communication overseas?

Since travel between countries and regions was common in Europe, the European Telecommunications Standards Institute (ETSI) established the Global System for Mobile Communications (GSM) to unify standards and eliminate the inconvenience of not being able to use mobile phones when traveling between countries.
With the exception of Japan and South Korea, which used their own proprietary standards, GSM was adopted in over 130 countries across Europe, Africa, Asia, and Oceania. At the same time as GSM, the SIM card system was introduced, making it convenient to use your phone abroad by simply changing your SIM card.
In the United States, multiple standards coexisted, including not only GSM but also CDMA and D-AMPS.

Current 2G communication situation overseas

In Europe, some 2G services have been discontinued, but the service is still in operation. In the US, 2G services have been discontinued.
2G services are available in Africa and Latin America.

Related columns:

• Using 2G Communications Overseas (Technical Column - Coming Soon)