It is no secret that what the U.S. cellular carriers call "4G" is really not 4G at all. It is really more like "pre-4G" or "3G+." Real "4G", as defined by the International Telecommunications Union, does not exist. Yesterday though, we got one step closer.
The ITU, a branch of the United Nations, announced yesterday the official standards for the next generation of wireless technology. Dubbed IMT-Advanced, the standard lays the rules of the road for what technologies like LTE and WiMax will eventually in to. What will the real 4G look like?
To understand IMT-Advanced, you need to know how we got to this point. If IMT-Advanced is truly the fourth generation of wireless technology, there obviously are three generations that preceded it. Let's take a quick look at the history.
1G (Pre-1990): Analog Mobile Phone System and Frequency Division Multiple Access (AMPS & FDMA). The forefather of all cellular technology. Think of satellite or car phones or those really big things that used to require a brief case to lug around. I am always reminded of Martin Cooper and the original one-pound cellphone and how people used to gawk at him while he walked down the street in New York City chatting away.
2G (1991-2000): Time Division Multiple Access and Code Division Multiple Access (TDMA & CDMA). This is where the great rift between AT&T and Verizon originated. Ma Bell used the TDMA standard while Big Red has been built off of CDMA and its evolutions. This is the era when cellphone became more commonplace but by no means ubiquitous. Cellular adoption ramped up through the 1990s as phones evolved, going from the relative blocks of Kyocera and Nokia to the concept of flip phones that would dominate well into the first half of the 2000s.
2.5G (2000-Present): General Packet Radio System (GRPS) and CDMA 1x. The rise of the data packet, BlackBerry and the first versions of the mobile Web through Wireless Access Protocol (WAP). Speeds at 2.5G were about 156 kilobits down per second.
2.75G (2003-Present): Enhanced Data Rates For Global Evolution (EDGE). The iPhone was originally an EDGE phone. This is a Global System for Mobile Communications (GSM) standard employed by AT&T and T-Mobile.
3G (2000-Present): Universal Mobile Telecommunications System (UMTS) and CDMA 2000. This is where we really started getting speeds that could handle full Internet data packets, up to 8 megabits per second down. This is also where the precursor to what the ITU calls "4G." Before announcing the standards for IMT-Advanced, the last standards that the ITU approved were for IMT-2000, what is generally considered to be 3G. GSM and CDMA continue to be separate and incompatible. This is also the beginning of the rise of in your face marketing from the carriers in the United States all claiming to have the fastest 3G networks.
3.5G (2006-Present): High Speed Packet Access (HSPA) and Evolution-Data Optimized Revolution (EV-DO). The approved 3G standard starts to evolve and speeds get faster and data is carried over cellular connections more reliably. This is the foundation that the current app economy is based on.
3.9G (2008-Present): Worldwide Interoperability for Microwave Access
(WiMax), Long Term Evolution (LTE) and HSPA+. When the carriers shout, "my 4G is blazing fast!" this is what they are talking about. Though this is not technically 4G, the ITU begin allowing carriers to market these technologies as 4G in December 2010 stating that any technology is that a significant advancement to the 3G standard can be called 4G. Speeds here have the potential to be up to 45 to 80 megabits per second down under ideal circumstances, which basically never exist. Currently, the best these standards can operate under real world conditions is about 14.4 megabits per second down. Sometimes higher, mostly lower.
Which brings us to today. IMT-Advanced is the significant jump of where these technologies can deliver reliable speeds of 1 gigabit per second down while stationary or 100 megabits per second while in motion (in a car, for instance). The technologies will be based on WiMax-Advanced and LTE-Advanced. This is also the end of the road for HSPA, which cannot evolve past its current form (though, with tweaks, can deliver speeds in excess of 100 megabits per second in ideal conditions).
IMT-Advanced is also completely IP-based and will be compatible with IPv6. IP will the prime pipeline of voice, text and data for all cellular technologies.
"IMT-Advanced would be like putting a fibre optic broadband connection on your mobile phone, making your phone at least 100 times faster than today's 3G smart phones," said François Rancy, director of ITU's Radiocommunication Bureau. "But it's not only about speed; it's about efficiency. IMT-Advanced will use radio-frequency spectrum much more efficiently making higher data transfers possible on lesser bandwidth. This will enable mobile networks to face the dramatic increase in data traffic that is expected in the coming years"
Do not expect IMT-Advanced "4G" to come around any time soon though. It has taken AT&T more than a year to start delivering LTE capabilities and it is still only in a handful of cities in the U.S. Verizon has a more advanced LTE infrastructure but the need to move more quickly was evident for Verizon as the CDMA infrastructure started to decay and hit a dead end that could not be evolved. Sprint uses WiMax through its partnership with Clearwire, but WiMax probably does not have a future in the U.S. (as far as cellphones are concerned). Sprint has also started deploying LTE. T-Mobile will continue to build out its HSPA+ capabilities though right now it is missing the boat on LTE and will have problems conjuring up the bandwidth and financial capital to develop its own LTE network (this was the prime driver of its attempt to be acquired by AT&T).
Also, do not expect the carriers to abide by the notion of "4G" as defined by the ITU. The marketing departments will not stand for it. IMT-Advanced will likely lead us into the new and exciting realm of "5G." It is the nature of how the environment operates.