FSO vs. Fiber Optic: Key Differences Explained

This article compares Free Space Optics (FSO) and Fiber Optic communication, highlighting the differences between the two technologies.

What is FSO (Free Space Optics)?

FSO is a wireless technology that transmits data through laser beams. It uses light waves to transmit data between buildings with a clear line of sight (LOS). The primary difference between Optical Fiber Communication (OFC) and FSO is that OFC sends data via light through a “fiber,” while FSO sends data via light through “air.”

How FSO Works (as per the block diagram):

• Information or data traffic is converted into pulses of invisible light representing binary 1s and 0s.
• The transmitter sends these light pulses into the air using an LED or Laser Diode (LD).
• A receiver at the other end collects the light using lenses and/or mirrors. It employs a photo-detector for this purpose.
• The received signal is processed and converted back into the transmitted information.

What is Fiber Optic Communication?

Fiber optic communication systems are widely used for long-distance telephone communication across seas and, increasingly, for transmitting internet data globally.

Unlike FSO, fiber optic communication utilizes optical fiber cables. The system includes a coder, a light source transmitter, the cable itself, a light detector, and a decoder. For very long-distance communication, repeater units are integrated into the chain to prevent complete signal attenuation. The latest advancement is the EDFA (Erbium-Doped Fiber Amplifier), which amplifies the signal directly in optical form without converting it to an electrical signal.

FSO vs. Fiber Optic: A Detailed Comparison

The following table outlines the key differences between FSO and Fiber Optic communication: