xGs: The Cellular Wireless Generations

4G Smartphone

Each generation of network technology has enabled a new set of features: 2G was about voice, 3G was about data and 4G is about video. 5G is expected to be about creating intelligent networks that can handle those billions of connected devices.


The nomenclature of the cellular wireless generations (G) generally refers to a change in the fundamental nature of the service, non-backwards compatible transmission technology, and new frequency bands. New generations have appeared about every ten years since the first move from 1981 analog (1G) to digital (2G) transmission in 1992. This was followed, in 2001, by 3G multi-media support, spread spectrum transmission and peak throughputs of 200 kbit/s; and in 2011 by 4G, which refers to all-IP switched networks, mobile ultra-broadband (gigabit speed) access and multi-carrier transmission.

1G:
First generation refers to the analog “brick phones” and “bag phones” as they were This was the first generation of cell phone technology.  Simple phone calls were all it was able to do. Cell phones began with 1G and signify first generation wireless analog technology standards that originated in the 1980s. A term never widely used until 2G was available. 1G was replaced by 2G wireless digital standards.

1G Phones

 
2G:
2G signifies second generation wireless digital technology. Fully digital 2G networks have replaced analog 1G, which originated in the 1980s. A few more features were added to the menu such as simple text messaging. 2G networks first commercially began on the Global System for Mobile Communications, or GSM, standard.

In addition to the GSM protocol, 2G also utilizes various other digital protocols, including CDMA, TDMA, iDEN and PDC. GSM is based on TDMA.

2G Phones

2.5G:
2.5G wireless technology is a stepping stone that bridged 2G to 3G wireless technology and is sometimes used to describe those evolved technologies that were first considered as being 2G. While 2G and 3G have been officially defined as wireless standards by the International Telecommunication Union (ITU), 2.5G has not been defined and was created only for the purposes of marketing.

As an interim step up from 2G, 2.5G has seen some of the advances inherent in 3G networks (including packet-switched systems). The evolution from 2G to 3G has ushered in faster and higher-capacity data transmission. Several technologies that have been considered as the evolutionary step to 3G include EDGE (part of the GSM family) and CDMA 2000 1X; at times these technologies are called 3G as they both meet some of the ITU requirements for 3G standards.
 
3G:
3G is the third generation of mobile phone standards and technology. 3G technologies have enabled faster data transmission speeds, greater network capacity and more advanced network services. This generation set the standards for most of the wireless technology we have come to know and love.  Web browsing, email, video downloading, picture sharing and other Smartphone technology were introduced in the third generation.  3G should be capable of handling around 2 Megabits per second.

3G Smartphones

3.5G:
Similar to the 2.5G acronym, the reference to 3.5G is not an officially recognized standard by the ITU. It is an interim or evolutionary step to the next generation of cellular technology that will be known as IMT-Advanced according to definitions by the ITU. IMT-Advanced will comprise the fourth generation of cell phone technology. The acronym 3.5G is also known as “beyond 3G.” 4G Americas does not use the terms 3.5G (or 2.5G) in respect of the official definitions provided by the ITU. The technologies within the GSM family that are considered as beyond 3G include HSPA+ and LTE. These 3.5G technologies are often called pre-4G as well.
 
4G:
4G is the term used to refer to the fourth generation of mobile wireless services that has been defined by the ITU and its Radiocommunication Sector (ITU-R) and established as an agreed upon and globally accepted definition in IMT-Advanced. The speed and standards of this technology of wireless needs to be at least 100 Megabits per second and up to 1 Gigabit per second to pass as 4G.  It also needs to share the network resources to support more simultaneous connections on the cell.  As it develops, 4G could surpass the speed of the average wireless broadband home Internet connection.  Few devices are capable of the full throttle yet. Coverage of true 4G is limited to large metropolitan areas.  Outside of the covered areas, 4G phones regress to the 3G standards.  We have a ways to go.  For now, 4G is simply a little faster than 3G.

4G Smartphones

A 4G phone has to comply with the standards but finding the network resources to fulfill the true standard is difficult.  You are buying 4G capable devices but the network is not yet capable of delivering true 4G to the device.  Your brain knows that 4G is faster than 3G so you pay the price for the extra speed.

4G LTE:
4G LTE– Long Term Evolution – LTE sounds better.  This buzzword is a version of 4G that is becoming the latest advertised technology but still not true 4G as the standards are set.  When you start hearing about LTE Advanced and WIMAX Release 2, then we will be talking about true fourth generation wireless technologies because they are the only two formats realized by the International Telecommunications Union as True 4G at this time.

4G WiMAX:
4G WiMAX - Worldwide Interoperability for Microwave Access – should be capable of around 40 megabits per second with a range of 30 miles.  It is one of the closest technologies to meet the standards of true 4G and as it develop should surpass the 100MB/second which is the 4G standard. Mobile WiMAX allows the use of high speed data transfers and is the main competition for the 4G LTE services provided by cellular carriers.