3G vs. 4G vs. 5G Mobile Networking Explained

of 05

3G, 4G and 5G Wireless - An Introduction

Wireless communication technology inside cell phones and other mobile devices have evolved over several decades. Dozens of different wireless connection and data transfer methods have been developed over the years - for improved speed, reach and/or reliability - although many are now obsolete.

The communications industry has classified these mobile network technologies into families spanning multiple generations. Networks based on the second, third and fourth generations have been widely adopted across the world and are named 2G, 3G, and 4G, respectively.These names are commonly referenced by Internet providers, the press, and companies selling various mobile network products. Unfortunately, the dividing lines between each generation of mobile networking have been blurred repeatedly and perhaps intentionally by different parties in the industry, resulting in much confusion over terminology.

of 05

2G (and 1G) Mobile Networks Explained

Wireless technology used in cell phones originally supported only voice phone calls. These cell networks were used in many cities across the world throughout the 1980s. No one called them 1G systems at the time, but still, they represented the first generation of mobile networks.


During the 1990s, as wireless communication technology improved, these original systems were gradually replaced with networks that supported data transfer in addition to voice traffic. In technical terms, these newer networks employed digital signal processing rather than the analog signaling of the earlier generation, most based on a technology called Global Systems for Mobile Communication (GSM). The terms 1G and 2G (the 'G' not related at all to the term gigabit) were coined together during this period.

Wireless data networking and 2G GSM obviously exploded in popularity as people began using mobile devices to connect to the Internet and/or business networks. Unfortunately, the data transfer speeds of original GSM systems were only 35-50 Kbps, similar to the performance of old dial-up modems.


An alternative to GSM, IS-95 was developed by Qualcomm during the 1990s, principally deployed in the United States and South Korea under its trademark name cdmaOne. The initial version of the standard (IS-95A) supported speeds of only about 14 Kbps but the later enhanced version (IS-95B) supported up to 115 Kbps. This 2G technology subsequently evolved into a set of 3G standard called CDMA2000 (see next page).


As the demand for cellular service grew, the industry refined these 2G technologies to support a larger scale of users and additionally increase speed. One enhancement to GSM called General Packet Radio Service (GPRS), ratified by the industry in 1997. GPRS ultimately became known as 2.5G as this technology was capable of somewhat higher speeds (up to about 110 Kbps) than base GSM.


Another offshoot of GPRS called Enhanced Data rates for GSM Evolution (EDGE) was introduced in 2003 and became known as 2.75G as it represented another performance increase over GPRS (typically offering about 135 Kbps to customers). Though gradually being phased out, EDGE continues to be used on many mobile networks even today as is satisfies the basic needs of both carriers and users in various parts of the world.

Significant confusion over the classification of mobile technologies into generational families began with EDGE. In some parts of the world, the final incarnation of EDGE technology is called 2.9G instead of 2.75G signifying the incremental improvements made to it in the years after its initial rollout. However, some also include EDGE on the list of 3G technologies (see next page).

of 05

3G Mobile Networks Explained

The International Telecommunication Union (ITU) created an industry-wide specification for 3G networking called IMT-2000, ratified in the year 2000.

Because EDGE technology was introduced at the same time other 3G technologies were competing for popularity and met the minimum technical requirements of IMT-2000, it was often included in press and industry marketing coverage of 3G. However, two other technologies significantly exceeded the minimum spec requirements for 3G and so became the primary platforms for 3G mobile wireless systems: CDMA2000, and Universal Mobile Telecommunications System (UMTS).


CDMA2000 became an official standard in 1999, leveraging technology from the earlier IS-95 (2G) standard. The first wave of CDMA2000 deployments, at the time called CDMA2000 1X (or sometimes 1xRTT), supported data rates up to 153 Kbps.

An offshoot CDMA standard, IS-856, enhanced the original CDMA2000 system by increasing speeds of data traffic. This technology eventually became known as Evolution Data Optimized (EV-DO) .Three forms of EV-DO - rev0, revA and revB - were successively developed and deployed to many mobile networks during the 2000s, each one offering additional speed enhancements over the preceding version. Original EV-DO offered theoretical speeds up to 2.4 Mbps, revA increased that limit to 3.1 Mbps, while the final revB version offers more than 10 Mbps. As with most wireless systems, the actual speeds of EV-DO vary greatly under field conditions and tend to be significantly less than these maximum numbers, often performing at rates less than 1 Mbps.


As a competing technology to CDMA2000, the original UMTS (sometimes also called W-CDMA) networks were designed for higher reliability wireless connections in return for somewhat lower data speeds. The first UMTS networks offered theoretical data rates of 384 Kbps. An enhanced version of UMTS called High-Speed Downlink Packet Access (HSDPA) improved the performance of connections in the downstream (but not the uplink) direction. HSDPA became a mainstream technology in 2006 with increased speeds up to 1.8 Mbps. Further enhancements to HSDPA eventually increased its download data rates up to 21 Mbps. HSDPA is often designated as a 3.5G technology given its significant improvements over base 3G mobile networks.

Another form of UMTS called High-Speed Packet Access (HSPA) emerged on mobile networks in the 2000s as providers combined HSDPA and the corresponding HSUPA technology for faster uplinks. The original HSPA supported up to 14 Mbps download and 5.7 Mbps upload data rates.

An enhancement to the HSPA standard called HSPA+ was ratified in 2008, increasing the theoretical maximum data rates to 84 Mbps downlink and 10.8 Mbps uplink. Some mobile providers marketed their HSPA+ based phone services as 3.7G. Airtel in Africa has marketed theirs as 3.75G.

As further explained on the next page, WiMAX and initial versions of LTE (Long Term Evolution) technology were heavily promoted as 4G but did not meet the full 4G technical specifications. Some people apply the 3.9G designation to these systems as a way to distinguish them from true 4G networks.

of 05

4G Mobile Networks Explained

Following their earlier work on creating the IMT-2000 specification for 3G, in 2008 the International Telecommunication Union (ITU) created the new specification for 4G, called IMT-Advanced. The 4G standard sets several requirements for mobile networks including mandating the use of Internet Protocol (IP) for data traffic and minimum data rates of 100 Mbps.

The industry originally referred to several different cellular networking technologies as 4G, but today, 4G has become synonymous with LTE (Long Term Evolution).

Several telecommunications companies including Clearwire Corporation and Sprint Corporation invested in a competing technology to LTE called WiMAX. A basic WiMAX installation offered customers maximum speeds up to 128 Mbps download and 56 Mbps for uploads.Several large WiMAX networks were built and deployed to consumers in 2008 (following an initial rollout in South Korea in 2006), but these networks are been phased out in favor of LTE.

LTE deployments began in 2010. While theoretically capable of 100 Mbps download speeds, initial rollouts tended to perform at rates closer to 10 Mbps, but as providers improve their infrastructure these rates have been improving on average.

Because the original versions of LTE and WiMAX both supported only about 50 Mbps maximum in the uplink direction, an industry debate ensued claiming that neither could claim the 4G designation. An official assessment of the ITU in 2010 agreed with this position, although ITU later relaxed their position as 4G quickly became a de-facto designation heavily marketed by both LTE and WiMAX providers.

The next version of LTE, called LTE-Advanced promises speeds much higher 100 Mbps plus various other technical enhancements. LTE Advanced rollouts should progress through the mid-2010s as some providers upgrade their original LTE installations and others migrate directly from older 3G systems.

of 05

5G Mobile Networks Explained

While the term 5G appears in the news occasionally, these technology standards are in early stages of development and likely to appear in the market only by 2020 at the earliest. Goals for future 5G include significantly faster speeds (a minimum of 1 Gbps and perhaps up to 10 Gbps) plus lower power requirements to better support huge numbers of new Internet of Things (IoT) devices.

Competition exists among groups in United States, Europe and Asia to be the leaders in 5G technology development. Meanwhile, as 4G evolves, it's also likely that newer versions of LTE will eventually be marketed as "5G" ahead of true 5G rollouts. And if 4G technology progresses well, the need for a new generation of mobile networks could be pushed out further in the future.