Communication technology is among the four main branches of technology that I discuss in this column. It has been some time since we explored it, so let’s remind ourselves that communication technology is when humans use tools, machines, knowledge and resources to control the environment by sending and receiving messages. It can satisfy a basic human need to communicate with other humans, but it also satisfies the need for people and machines to communicate, and for machines to communicate with each other as well. Communication technology is essential to our way of life, providing the interconnectedness that we all enjoy and rely on to some degree or another.

All communication technology involves messages. These messages are composed of data or information, which are general terms used to describe the message content. Data are relatively small, individual, unorganized and nearly useless “bits” of messages, while information is larger collections of data that have been organized. If we think of a message as a word, data may be thought of as the individual letters used to compose the word. By themselves, the letters mean nothing except to represent a sound or the ancient idea from which they evolved from, but when combined in an organized way to create words and sentences, data creates the information the written message contains.

A critical step in the communication process is transmitting (or moving) the data. Transmission can occur in many ways and typically involves using energy to encode the data into a form that can be transmitted. One example of transmission is electrical signals moved over copper wires. Another is radio waves transmitted using antennas and radios. Another way to encode and move messages is by using light energy. A very simple example of using light to transmit a message is the stop and go lights used on a traffic signal. Green means go, yellow means caution, and red means stop. The light is used to encode those messages. But light messages from a traffic signal have many drawbacks. The message can’t be seen from a great distance (of more than a mile or so), it can only handle very simple messages (go, caution, and stop), and it can only transmit one message at a time. If light is to be used to send far more complex messages, over much longer distances, and at much faster rates, some other method of transmission is needed. This is when fiber optic cable can be used.

Fiber optics is the backbone of modern communication, and it uses light to transmit data through thin strands of glass or plastic. Internet communication relies heavily on fiber communication networks. If you were to look closely at a fiber optic cable, you would see hundreds, or even thousands, of extremely small diameter glass strands with a color-coded plastic cladding around each strand. Imagine these glass strands as ultra-thin highways for light signals, where information is encoded and sent in the form of light pulses. The core of a fiber optic cable, through which light travels, is surrounded by a cladding material with a lower refractive index, ensuring that light remains trapped within the core and bounces off the walls, minimizing signal loss. So, when a pulse of light is sent into a fiber optic strand, it travels along the inside of the strand at the speed of light, constantly reflecting along the inside of the strand until it reaches its destination. Because the glass strands are pure glass, the light has nothing to block it and can transmit the light pulses with near perfect accuracy.

To create the light pulses sent along fiber optic cables, light-emitting diodes (LEDs) or laser diodes are used to generate the light signals. These signals, carrying vast amounts of data in the form of binary code, are then transmitted through the core of the fiber optic cable. The choice between LEDs and laser diodes depends on the specific requirements of the application.

One of the most compelling aspects of fiber optics is its incredible data transmission speed, often measured in gigabits or even terabits per second. Traditional copper cables pale in comparison to the speed of fiber optics, making them the preferred choice for high-speed internet connections, telecommunications, and data centers. The speed of light itself is a limiting factor, and fiber optics come remarkably close to achieving this maximum velocity in transmitting data. The ability to transmit vast amounts of information with minimal delay has revolutionized the digital landscape, enabling seamless communication and data exchange on a global scale.

If you spent any time driving around Rochelle recently, you probably noticed the utility work that was being done along the west side of Illinois Route 251. Workers were steadily digging holes along the right-of-way and installing fiber optic conduit and cables. Each time I drove past I noticed workers down in the holes with shovels, and it looked like back-breaking work. These workers are essential to providing the modern communication technology conveniences we all rely on because it is difficult and tedious work to route the delicate cables underground where there are so many obstacles. Hopefully having a basic understanding of communication technology, and the fiber optic cables that are part of it, will give you a better appreciation for the effort as well as the benefits we all enjoy from it.

Kurt Wolter has studied and taught technology - including production, transportation, energy and communication - for over 30 years. He enjoys trying to better understand technology and its past, present, and future while also attempting journalism. He can be reached at technohistory100@gmail.com.