When the first mobile phones hit the market, many people were surprised by the advancement of their technology. In fact, it was simply amazing that a very small communication team could send and transmit voice messages. It was more clearly advantageous than a two-way radio that was all the rage in those days when you can only call your base stations and other radio terminal users tied to your channel. Most of the people using two-way radios were hobbyists or employees of a company with a base to contact field employees to monitor their whereabouts. The advantage of a mobile phone compared to these two-way radios was the longer range power of a cell phone, whereas a two-way radio has a limited operating range.

At this stage, however, mobile phones, although they already use cellular technology through channel reuse, were still considered in their initial stage, since the carrier used is analog technology. But first, so that you can better understand how a mobile phone works, let me explain the term channel reuse to you. You see, radio signals operate on a particular frequency. These radio signals, to be free from interference, must operate on a different frequency. As if a certain radio frequency is on 120 MHz, another radio frequency must be on another frequency to avoid mixing signals with the radio signal that is already operating on the 120 MHz frequency. But in the case of mobile phones, many of these units They operate on the same frequency, using the principle of channel reuse, which makes mobile phones used by many people. Channel reuse was made possible by providing limited power to each mobile phone unit and by providing many cell sites or towers. Therefore, a mobile phone can relay and receive signals only to the closest cell site or tower and not affect another cell tower at another location, making it possible for other cell phones on the same channel to send and receive signals at other sites. cell phones. or towers without interference.

Now that you have a good idea of ​​how the cell phone works, let’s go back to the first operator used by cell phones which is the analog radio signal transmission system. These types of radio signal carriers are the upstream and downstream frequencies of radio transmissions that were used in all forms of radio messages before the advent of digital technology. A very good example of these signals can be seen in hospital operating rooms that are usually found on television and in movies showing the near death of an individual, as shown by the up and down movement of a moving light. on a monitor chart. The up and down light you see moving is an analog signal frequency, representing the sound of a patient’s heartbeat.

When digital signals became available for use in radio communications, it was discovered that the channel reuse system used in mobile phones is more adapted to the use of the digital carrier signal system, since digital signals are not susceptible to interference to Difference from analog. Thus, telecommunications companies soon began to rebuild their signaling system to adapt to the digital signal delivery system in mobile phones.

It was at this stage that a communications company in England was able to develop a digital communication system known as Short Messaging Service or SMS for use on mobile phones using the digital signaling system. By the way, SMS can only be possible with a digital operator, but never in the old system that was the analog operator. The development of the SMS or texting capability of mobile phones was actually designed to be used by the deaf and dumb segment of the community. But now we know what happened to this type of communication for the deaf and dumb.