This article describes the evolution of mobile communication technology from the first generation (1G) to the fourth generation (4G) and the resulting changes in user experience. It covers the evolution from analog communications in 1G to high-speed data transmission in 4G, and introduces the differences and key features of each generation of technology, especially the technological innovations used in 3G and 4G.
Smartphones are a topic that many people are interested in, and it’s a topic that never fails to come up in any gathering of two or more people. The interest in smartphones has spread not only among young people, but also among our mothers’ generation. In fact, my mother often asks me questions about smartphones, and sometimes she even teaches me features I didn’t know about. Recently, the terms 4G and LTE have been popping up in advertisements and articles, piquing people’s curiosity. It’s widely known that 4G is an evolution of 3G, but whenever a new technology comes along, people are both afraid and curious. People have different opinions about which is better, and it can be confusing.
I’m a medical doctor, but I’m also very interested in telecommunications, so I often find myself explaining 3G and 4G to people around me. I’d like to take this opportunity to explain in detail the evolution of cellular technology and the differences between 3G and 4G that people may not be aware of.
The history of cellular technology is divided into generations (G), each of which has seen major technological changes. The first generation of mobile communications (1G) was the beginning of wireless communications, and while there was wireless equipment before, it was only with 1G that phones became available to the general public. Cell phones at that time were the size of a human head and had a black, clunky appearance. This led to many funny anecdotes. The 1G communication method still transmitted voice in analog form and transmitted data over frequencies. A frequency can be thought of like a road, and at the time, 1G was like a one-lane road, with only one vehicle (i.e., one user) per frequency. The number of users per frequency was limited, and capacity and transmission speeds were slow.
To address these shortcomings of 1G, second-generation cellular (2G) was introduced. In 2G, analog signals began to be converted to digital signals and transmitted, increasing the number of users and commercializing the technology. The digital signal transmission improved the quality of voice calls and made it possible to send text messages. Another big change in 2G was the introduction of CDMA technology. This technology stretched single-lane roads into multiple lanes, allowing more users to communicate simultaneously on the same frequency. This greatly increased communication capacity.
While 1G and 2G are considered the telecommunications technologies of the past, it is 3G and 4G that are now widely used. The third generation of mobile communications (3G) enables high-speed data communications, allowing not only voice calls and text messages, but also larger data transfers. There are two main technologies used in 3G: W-CDMA and CDMA2000. W-CDMA is a form of UMTS technology that was developed based on GSM in Europe and is the most widely used 3G standard worldwide. CDMA2000 uses satellites to synchronize signals, which is different from W-CDMA, which does not use satellites. W-CDMA uses a cellular SIM card (USIM), which makes it easier to transfer personal information when changing phones. CDMA2000, on the other hand, does not support USIMs, which is inconvenient.
When it comes to fourth-generation (4G) mobile communications, the most commercialized 4G technology is LTE (Long Term Evolution). However, to be clear, LTE is more of a 3.9G technology than 4G. Full 4G is a technology called LTE Advanced (LTE-A), which theoretically offers speeds more than 12 times faster than 3G. 4G’s speed boost is made possible by a wireless multiple access technology called OFDMA (orthogonal frequency division multiple access). This technology allows multiple users to communicate with a single base station at the same time.
OFDMA is a technology that allows multiple frequencies to be used simultaneously, which allows multiple signals to be transmitted in parallel without interference, even in narrow frequency bands. To put it simply, if traditional communication is like a single stream of water coming out of a faucet, OFDMA is like multiple streams of water coming out of a shower. However, to prevent interference that can occur when multiple frequency signals are transmitted simultaneously, the frequencies are spaced apart by an integer multiple to prevent collisions between the signals.
Advances in communications technology have allowed us to transmit more data faster, all thanks to advances in the efficient use of frequencies. The speedup between communication generations depends on how much data can be reliably transmitted in a limited frequency band, and future communication technologies will continue to evolve in this direction.
