3G, 4G, 5G, why do we need so many "G"?

 This can happen with our cell phones receiving signals using the same frequency band, so how do we connect many cell phones to one cell tower and vice versa, the simplest solution is to give each one a different band, cell phones can be distinguished by their bands, cell towers can be separated to send and relay through the network, the key is that we only have a fixed number of frequencies. But because radio waves have many different uses, such as air and sea navigation, television broadcasting, and even bands used by amateur radio enthusiasts. So in the earliest days of cell phones, not all frequencies were freely available to cell phones, and some cities only had two megahertz of bandwidth available for about 30 people at a time, and many efforts to improve telephone networks over the years have come from addressing this problem. 4G or 5G refers to the new generation of technology used to send radio waves, and naturally, it all starts with 1G, where users close to a given cell tower will be given a specific different frequency band, which engineers call this frequency. Domain multiple access or FDNA but a key breakthrough involves the idea of how frequencies are used in physical space is to divide the area into a kind of cellular pattern, where Each cell transmits using a different cell tower or base station. The trick is that nearby cells are assigned different frequencies to use, but distant cells can use the same frequencies without overlap. This reduces the likelihood of interference because people using the same frequency band may be communicating with completely different cell towers, which in short means we can reuse certain frequencies and get more people onto the network because there is more bandwidth and we can use 2G over and over again, making things more efficient, and part of the reason for this success is time division multiple access or TD. Different phones can use the same frequency band, it's like having two people in a room speaking to you in similar voices, if they say the same thing at the same time you can't understand what they are both saying, but oddly enough imagine them taking turns saying individual words of their message so you might hear them clearly. But it's not just two people, although it's confusing for one person, but the machine can easily keep track of different messages in time. It happens so quickly that you can't feel the interruption because many people can now use the same frequency band, and we become more efficient. Using interference-free bandwidth and more bandwidth brought more data because 2G let us do more than just voice calls and allowed us to text and even send picture messages. Then came 3G, which took things a step further, and with 3G we started to rely heavily on what's called code division multiple access or CDMA. this time, let's say four people are in a room and two people are talking at the same time, but one of them is at the other end of the room speaking in Chinese and the other is at the other end of the room, and a person fluent in Spanish and another person fluent in Chinese are both listening to the speaker, because Chinese and Spanish are pronounced so differently that each person ignores the language they don't understand. It focuses on what they are doing, which is their respective messages. In the cellular world, base stations can be programmed to listen to a large number of signals at the same time and decode them in different ways while playing the role of different translators, so CDMA allows signals from different phones to send the same frequency at the same time and be separated again at the other end, which allows us to make better use of the frequency band and send more data with more 3G users. We gained the ability to send email, browse the web and even watch videos, and I know that in reality, the codes in CDMA are sometimes similar enough to each other that they can cause problems in the room. The languages are probably more like Spanish and Portuguese. They're different languages, but they share some grammar and vocabulary, and it can sound confusing once engineers figure out some other tricks to deal with the problem, like changing the power of the signals used to communicate with different cell towers to help distinguish between the different signals. With that comes 4G, which is, you guessed it, more powerful. The bandwidth from the available frequencies to accommodate the rapidly growing number of cell phone users who are eager for data engineers to implement what is called orthogonal frequency division multiplexing or OFDM, even though everything we have mentioned so far is so that the bits of the signal sent through the contiguous bands actually interfere with themselves, this is because similar frequencies may have a bit of distortion when propagating through the air and when bouncing in the air will The larger the band, the greater the possibility of getting around this problem, FDAN splits the individual bands into smaller parts called carriers, and the frequencies in these parts are less likely to interfere with each other because they are orthogonal, just like CDMA and 4G codes, and the result of all this is the ability to use a wide band to enable BIOFDM to send more data to the phone through all these techniques We can reuse almost the entire spectrum in each cellular service for cellular communications through the towers to provide more bandwidth for everyone, but it also presents some problems at the edge of both cells. Using the same frequencies, we end up with interfering signals again When you are near a tower, this is not a problem, but when you are between two different cell towers, the one your phone is communicating with may be using similar frequencies to its neighbor, and at the cell boundary, the strength of each of their signals may be roughly the same. Unfortunately, there may be signal interference, but neither will provide reception, which we call inter-cell interference or ICK. This is currently an unavoidable problem with modern cellular networks, and there are tricks that can help solve this problem by utilizing signals from both towers, or even from both towers at the same time, which is one of the features of 4G that also helps reduce blind spots, but even so, a new stumbling block in the way is about to appear. One of the features of 5G and all of its promised data is a network of so-called ultra-dense networks, which consist of many smaller cells that provide reception to many users. The problem is that with many tiny cells we end up getting more boundaries, increasing the number of blind spots, which doesn't mean your phone is receiving full data, engineers are aware of this problem and are already trying to develop techniques to expand bandwidth without causing a lot of interference. We hope that our information and communication technology will become more and more powerful and bring us a more convenient life experience. Translated with www.DeepL.com/Translator (free version)