Photo of a Wi-Fi Tower Under a Blue Sky

It is hard to imagine the world of today without wireless networks…

Posted on March 12, 2024

It is hard to imagine the world of today without wireless networks – either for giving devices internet access through Wi-Fi or connecting peripherals using Bluetooth.

And yet these game-changing technologies did not spring up overnight. The evolution of wireless technologies has continued in tandem with the development of computers, even if their transformation into their current forms is recent. Let’s take a look at this journey.

The Spark: Radio Transmitters

The spark of wireless communications was a literal spark – or rather a spark gap transmitter. This was the first form of radio, using high-voltage sparks to create radio pulses. Of course, this form was too limited to actually transmit audio. But by using Morse code, it could indirectly send messages over much longer distances than through any traditional method.

This started the era of the wireless telegraph, laying the groundwork for the wireless communication grid of today.

Vacuum Tubes: The Switch to Continuous Waves

While spark gap transistors worked well enough for Morse code, audio transmission (let alone video) required continuous radio waves, not the pulses the sparks could create. This only became a practicality when vacuum tube transistors entered the picture.

This was the start of proper radio transmissions, using Amplitude Modulation (AM) and later Frequency Modulation (FM) to package audio signals into these continuous waves and broadcast information to the public at large.

But while the vacuum tube technology was cheaper to set up than spark gap transmitters, it still wasn’t cheap (or small) enough to be used for personal communication. Something more was still needed.

Transistors: The Final Puzzle Piece

Transistors are often considered one of the most pivotal inventions that heralded the digital age and with good reason. It is transistors that paved the way for electronics, whether we are talking of integrated circuits and microprocessors or walkie-talkies and later mobile phones. This is because transistors allowed wafers of semiconductors to perform the same function that a bulky vacuum tube did, with a fraction of energy and production cost. And even in their early days, these semiconductor transistors were smaller than any vacuum tube transmitters, making portable transmitters possible.

Walky-talkies were of course the first form of this portable communication, with its limited range and communication channels. But this soon paved the way for cell phones and eventually, Wi-Fi, powered by a global grid of cell towers and satellites.

But What About Interference?

Wireless communication is certainly convenient, but it has an obvious flaw; if multiple devices are transmitting information in the same airspace, don’t the signals get jumbled up?

The fact that we don’t run into any such issues right now is only because of a rigorous set of standards adopted and enforced by the industry. In the early days of radio communications, signal interference was a problem.

With spark plug transmitters this was difficult to get around, as it produced chaotic radio pulses with noise intruding in a wide range of the detectable spectrum. This is why when better technologies were developed, it was eventually banned.

But how do the better technologies handle it?

How Wireless Communication Standards Work

The method employed to avoid signal interference between multiple devices is simple in theory: reserving certain sections of the spectrum for specific uses. For example, an FM radio broadcast uses a very different part of the spectrum than your home’s Wi-Fi.

But what about multiple devices using the same type of network? That is where specific standards like Bluetooth or Wi-Fi come along.

The whole purpose of these wireless communication standards is to lay down the protocols that must be followed by adhering devices to prevent any signal interference and allow for efficient usage of the bandwidth. This is what lets you connect multiple wireless devices to the same network seamlessly.

Are These Things Still Relevant Today?

The evolution of technology does not stop. We may have solved the problems of before, but with new developments come new challenges requiring their own fixes.

The Internet of Things, for example, has exponentially increased the number of devices expected to connect to a wireless network. This calls for even more efficient and robust communication protocols, not to mention more bandwidth requirements.

The upcoming Wifi 6 is a big step in this direction, bringing an entirely new band of wireless spectrum (6 GHz) that can be utilized more accurately by high-frequency

communication. This will improve data transfer speed as well as latency even in the most crowded installations.

And so wireless networks continue to improve, becoming safer and faster with every generation.