Fiber Optic Communications Explained
Fiber optic cables are flexible transparent tubes that transport information by using light-based technology. These fibers are able to send a wide variety of information across a long distance. In one scenario, a computer user connects to a laser that converts electrical information into light pulses and fires them down the cable. At the other end, the receiver’s computer would need a photoelectric cell to receive the light pulses.
The technology behind fiber optic communication has made it possible to use many independent channels, each using a different wavelength of light to transmit data. These independent channels are known as solitons. The per-channel data rate is the total of the data rates minus FEC overhead. Commercial dense WDM systems can carry 80 channels. The 2016 Nokia/DT/TUM result was very close to the Shannon theoretical limit, while the 2020 RMIT/Monash/Swinburne result was very near the theoretical limit.
The bandwidth of fiber optic cable increases as the distance is increased. The bandwidth of a fiber optic link remains at least 10 MHz even if it is stretched over long distances. With proper modulation, fiber optic links can handle data rates in the tens of Megabits per second (MBPS) and higher. Gigabits per second and Terabits per second are also supported by fiber optic cables. The technology is more complex and expensive than any other form of communication.
Modern fiber optic systems can carry multiple independent channels using a different wavelength of light. These channels are called channels, and the per-channel data rate is the total per-channel rate minus FEC overhead. A commercial dense WDM system can carry up to 80 channels. The 2016 Nokia/DT/TUM results are close to the Shannon theoretical limit. The 2020 RMIT/Monash/Swinburne result is very close to it.
A fiber optic cable can carry a large number of different independent channels, each channel using a different wavelength. The per-channel data rate is called the net data rate. The average speed of a fiber optic cable depends on the number of channels. A single-mode fiber can support up to 512 independent channels, but is not always efficient. It’s possible to upgrade to a commercial dense WDM system at a cost of about $20 million.
A fiber optic cable’s bandwidth decreases as it becomes longer, but it’s always higher than 10 MHz. The resulting data rate of a fiber optic link is generally in the tens of MBPS, depending on the length of the cable. The efficiency of the network is also determined by the amount of energy used in using fiber optic cables. Moreover, a fiber optic cable requires only a minimal amount of energy, which makes it more cost-effective.
A fiber optic cable has multiple layers. A single mode has a thin core, while a multimode has multiple layers of materials. A multimode fiber contains multiple layers. A single mode is thinner than the other. Its core is surrounded by a plastic layer, which is two times as thick as the core. The outer jacket is made of tough material such as Kevlar. The speed of a cable’s light is a factor in the price.