RF modules in the PC, this is how WiFi, Bluetooth and others work

Initially, RF modules were not part of the hardware of our computers, we owe our existence to the emergence of mobile phones in the 90s. Development that allowed the creation of modules of this type with reduced size and consumption.

Radio frequency is everywhere

Today, if we look everywhere, radio frequency or RF is everywhere and integrated into all types of equipment. We can see that this is integrated into mobile networks such as 5G, radio, Bluetooth interfaces, etc. They are all based on the use of radio frequency, in which each standard operates at the speed of the radio frequency spectrum, which ranges from 3 kHz to 300 GHz.

However, we often think of wireless interfaces as new in the era of the mobile Internet. All of a sudden, in the era of streaming television, we forgot that the images reached our television over radio frequency, and we were going to see another Internet based not on telecommunications networks, but through satellite television. The project, which, like a historical anecdote, Microsoft was involved in the first half of the 90s, when the name of the Internet was known to few.

In the early years of the Internet, we connected not via a Wi-Fi interface, but via a modem connected to the telephone network using an RJ-11 cable. At a time when we have wireless internet and where the PC or console controller is no longer tied to a cable, RF modules are everywhere.

The basis of all RF modules

The RF module is responsible for sending and / or receiving information via radio signals at a specific frequency. They can be represented in three different ways: transmitter, receiver, or transceiver. In the case of transmitters, they can modulate the data as radio waves so that the receiver can demodulate it. Whereas the transceiver can do both tasks at the same time.

RF modules do not transmit information in digital and therefore binary form, so simply changing the modulation beyond what is expected means changing the information. Given that the equipment with which we process data uses binary values, it is necessary to have equipment that encodes, in accordance with strict rules for each communication standard, a binary message in radio waves that the corresponding receiver can understand.

Radio frequency was banned in early computers

The first computers used dedicated monitors and could not be connected to a television, despite using the same picture standard. The reason for this is that it was forbidden to start a computer with a built-in radio frequency module, which was necessary for signal transmission. from the video. At that time, the video port was predominantly an RF port to which an antenna cable was connected, which required the emitting unit to have an RF transmitter inside.

Since it was at the height of the Cold War, in the United States, the FCC of that country, and where the slot machine industry first emerged, since the first consoles and computers came along, they did not come with a built-in RF module for transmitting signals. subscribe. So they had to do it via composite video. Although, years after the launch of the first generation of computers, this limitation was removed, which allowed computers to appear that could work on television, having a radio frequency module integrated into the equipment. A practice that we have not seen in all the hardware.

But RF modules for wireless data transmission didn’t really matter until the 90s. Before wireless interfaces were talked about, they were radio frequency optical interfaces. This required the emitter and receiver to be aligned within a certain range with respect to each other, and did not give users freedom of movement.

2.4GHz, universal wireless frequency

In 1985, the FCC announced that the 2.4 GHz frequency could be used without a license. This means that it is not necessary to be an authorized radio operator in order to transmit radio, no matter which network operates on that frequency. At the same time, it became possible not long-distance radio communication, but the creation of wireless interfaces through radio frequency modules. First apps? Car keys that open automatically remotely, garage doors also open automatically. Although nothing about wireless networking

This continued until 1991, when the NCR Corporation and the American telecommunications company AT&T invented the WaveLAN technology. This was the immediate predecessor of what we know as Wi-Fi. The trade name given to the protocol when it became a communications standard is IEEE 802.11, losing the WaveLAN trade name in the process.

Bluetooth is another radio frequency-based technology, but unlike Wi-Fi, it has become the standard for wireless communication between peripheral devices. This is a technology originally invented by Ericsson in 1994. Whereas Wi-Fi was invented directly for the telecommunications world. Bluetooth was invented as a wireless replacement for the RS-232 communication standard using the 2.4 GHz frequency. In general, 2.4 GHz has always been used for wireless communication through all kinds of peripherals, not only those based on Bluetooth and Wi-Fi standards, but also the proprietary systems that some manufacturers use to communicate their wireless mice and keyboards with PCs. …