Fiber optic cables are used to transmit data encoded in pulses of light. Thin strands of glass inside the cable reflect the light as it travels along the length. By encoding data in pulses of light, fiber optic cables can transmit large volumes of data over long distances.
There are two types of fiber optic cables. While they both follow the same fundamental principles, there are subtle differences in how they achieved data transmission.
Let’s take a closer look at the two types of fiber optic cable and how they differ from one another.
Multimode
Multimode fiber optic cables can carry multiple signals simultaneously. A series of techniques known as wave division multiplexing enables these individual signals to travel along the same cable without interfering with one another. Once they reach their destination, these same techniques are used to separate out the individual signals from one another.
Multimode fiber optic cables come into varieties. First, there is step-index multimode fiber; the other is graded-index multimode fiber. Step-index multimode fiber is usually used for transmission of data over relatively short distances. As light travels down a fiber optic cable, the light rays will often bounce off the cladding around the core. Only a relatively small portion of the light takes the most direct route through the cable. Because of this, light arrives at the Endpoint at slightly different times.
On the other hand, graded-index multimode fiber utilizes a core with a diminishing refractive index. The further away from the core you move, the less the refractive index. A high refractive index in the center of a graded-index fiber optic cable enables the light rays in the cable’s center to travel down it slower than those nearer to the cladding. But by curving light in the court helix rather than zigzagging off the cladding, it is possible to make both lights signals arrive simultaneously.
Single-Mode
Single-mode fiber optic cables utilize a smaller core than multimode cables. The small diameter of the core of a single-mode fiber optic cable means that only a single light signal can be transmitted along at any one time.
However, as a consequence of this smaller core, light passing through a single-mode fiber optic cable is less susceptible to attenuation. Therefore, a single-mode fiber optic cable can be used to transmit data over longer distances than a multimode cable. High bandwidth and long-distance networks tend to use single-mode fiber optics in place of multimode.
Which Is Better?
Both single-mode and multimode fiber optic cables have their own use cases. Neither is inherently better than the other; it all depends on what you want to do with them. Single-mode fiber optics are better suited to transmitting large volumes of data over long distances. However, multimode fiber optic cables allow for multiple signals to be transmitted simultaneously.
These two types of fiber optic cable account for virtually every fiber optic on the market. The type of fiber optic cable used is only one factor determining how effective they are at transmitting data from A to B.
