Fundamentals of Telecommunication: Analog Systems vs. Optical Fiber

Analog Telecommunications Systems

Analog telecommunication systems utilize electromagnetic transmissions to send signals over long distances. This technology was one of the biggest technological phenomena of the 20th century. Analog systems are based on the transmission of electromagnetic waves where the intensity or frequency is controlled. Examples include the telephone, radio, and TV.

Television (TV) Transmission

Television is a telecommunication system designed for the remote transmission of moving images and sound. Image capture and subsequent viewing require a series of receiver devices. Color emissions utilize three separate electron beams (red, green, and blue).

How the Telephone Works

The operation of the telephone is based on the conversion of sound waves into electromagnetic waves. These waves are transmitted by cable or radiated wave to the receiver, where the reverse process occurs.

Key components:

• Microphones: Devices that convert sound waves into an electrical signal of variable intensity.
• Earpieces (Headphones): Perform the inverse function of the microphones; they transform the received electric current into sound waves, often using an electromagnet.

Signal transmission can be done either wired or wireless.

Radio Communication: AM and FM

Radio is a wireless telecommunications system used for the transmission of sounds converted into an electromagnetic signal, sent from a transmitter station to a multitude of receivers. Thanks to the microphone and the radio station, the sound is radiated as a wave.

In the receiver, radio waves are transformed into sound waves emitted by the speaker. The main differences between radio and telephony are wireless transmission and the direction of the broadcast message. Radio utilizes Amplitude Modulation (AM) and Frequency Modulation (FM).

Optical Fiber Technology and Limitations

Optical fiber highlights the possibility of sending up to 100 beams of light on the same fiber, each with a different wavelength. This technology achieves extremely high transmission speeds.

However, optical fiber presents specific challenges:

• The glass fiber is fragile and difficult to repair in case of breakage.
• Connections are complex.
• Signals, encoded as light, must be converted into electrical signals to be used by devices.

This system is also suitable for short-range transmission.