Fiber Optic Cable vs Twisted Pair Cable vs Coaxial Cable Guidance

There are three mainstream types of network cables: fiber optic cable, twisted pair cable, and coaxial cable. They are very different from each other, and they are also different in the application of a communication system. This article will introduce the features and specifications of fiber optic cable, twisted pair cable, and coaxial cable, and clarify the differences between their performance and capacity.

 

What Is Fiber Optic Cable?

 

Fiber optic cable is a type of Ethernet cable, which is a very thin and ​pure glass cable. Comparing the transmission capacity of optical fiber cable and twisted pair cable, the former is 26000 times higher than the latter. Its working principle is total internal reflection, when the light pulse passes through a small glass tube, the optical fiber cable transmits data over a long distance. 

 

The fiber optic cable actually consists of core and cladding, the core is responsible for carrying the light signal, and the cladding is a glass layer around the core. The refractive index of the core is higher than that of the cladding, resulting in the total internal reflection within the core. Most fibers operate in duplex pairs: one for transmission and the other for reception. 

 

Figure 1: Fiber optic cable

 

There are two types of optical fiber cable: SMF and MMF, which stand for Singlemode fiber and multimode fiber separately. The difference between single-mode fiber and multimode fiber is that multimode fiber has a larger core and can transmit multiple light rays and modes at the same time, while single-mode fiber can only transmit one mode. The most used single-mode optical fiber cable is the OS2 cable, and the multi-mode optical cable is OM1, OM2, OM3, OM4, and OM5. The maximum transmission distance of a single-mode optical cable can reach several kilometers, while the maximum transmission distance is up to 550m in a 10G network. Click here to get more information about fiber optic cable.

 

What Is a Twisted Pair Cable?

 

Inside the twisted pair are two separate insulated wires, which are twisted together in the constituent of twisted pair and made parallel to each other. The twisted wire pairs can prevent the crosstalk generated by adjacent pairs. It is mostly used in telephone communications or modern Ethernet networks.

 

Figure 2: Twisted pair cable

 

Twisted pair cabling is generally used to help prevent signal interference. Now, the twisted pair Ethernet cable can be divided into unshielded twisted pair(UTP) and shielded twisted pair(STP). UTP is usually used in Ethernet installation, STP cable has better resisting noise ability than UTP cable, so it is commonly used in various networks to avoid crosstalk and electromagnetic interference. The main difference between the UTP and STP is STP copper cable gets an extra foil wrapping, the four pairs of wires in the STP cable are wrapped in an ensemble metal braid or foil.  The twisted pair cable has a more suitable bending radius, easier termination, and provides more functions when selecting network topologies. Click here to know more about UTP and STP.

 

What Is Coaxial Cable?

 

Coaxial cables are often used by cable operators, telco, and Internet providers to transmit data, it is also applied to voice and video data systems. Since it was invented in the early 20th century to the present, it has won a large number of markets with the advantages of reliable and accurate transmission. With the development of technology, this technology has also changed from commercial to civil and is widely used in families.

 

The coaxial cable is designed to prevent EMI by surrounding an insulating layer and conductive shielding to the inner conductor. The outer jacket is also an insulating layer. The electrical signal transmits over the center conductor. Through the shielding structure, the coaxial cable can be connected between two devices, and the maximum link length becomes bigger.

 

Figure 3: Coaxial cable

 

The commonly used types of coax cable are RG59 and RG6, they are most used in residential applications. The ''RG" stands for radio guide in the earliest period of World War II, but now it does not refer to any practical meaning. Comparing the RG59 with the RG6 coaxial cable, the RG59 coax cable is thinner and the shielding is less, the RG6 coax cable has a heavier gauge and thicker insulation layer so that it gets better shielding. The application of them is also different. The RG59 is used for cable TV transmission and short cable links. The RG6 coax cable is more used in digital video signals and satellite TV.

 

Comparison of Coaxial Cable vs Twisted Pair vs Fiber Optic

 

We have introduced there are differences in structure, performance, and capacity of optical fiber cable vs twisted pair cable vs coaxial cable. In the next part, we will mainly introduce the difference in performance and capacity.

 

Performance

Both Coaxial cable and twisted pair cable are made of copper with a surrounded insulating layer with other materials, while optical fiber cable is made of thin and flexible glass tube or plastic tube. These three types of cables can transmit electrical signals in television， telephone, and data areas, but optical fibers have wider bandwidth, higher transmit speed, and higher frequencies.

 

Cable Type	Speed	Bandwidth	Distance
Coaxial cable	-	750 MHz (default)	Up to 500m
Twisted pair cable	Up to 10 Gbps	Up to 4700 MHz	Up to 100m
Fiber optic cable	10/100/1000 Mbps, 10/40/100/200 Gbps	Up to 4700 MHz	Up to 80km

 

Installation

The fiber optic cable is weaker and thinner than twisted pair cable and coaxial cable, so it needs to be more careful when installing, operating and maintaining. coaxial cable can reach a longer distance than twisted pair cable. Because the dielectric insulator is wrapped around the copper core in the coaxial cable, engineers need to disassemble and package the wrapping layer when installing and maintaining it, which makes the coaxial cabling installation very difficult.

 

Price

In general, fiber optic cable will be more expensive than copper cable because it has better performance. However, in practice, the prices of these three cables will change due to being supplied by different vendors.

It can be seen from QSFPTEK that the price of fiber optic cable of the same length is the lowest. But due to the use of other optical components, especially optical transceivers, the total installation cost of optical fiber cables may also be high. In addition, the cost of a twisted pair cable with an RJ45 connector is lower than that of a coaxial cable with a BNC connector.

 

Conclusion

After the introduction of this article, you should have a sufficient understanding of these three kinds of cables. Optical fiber will become the mainstream of data transmission in the future because of its significant advantages, while twisted pair and coaxial cable play an essential role in a large number of relevant fields because of their price advantages. QSFPTEK provides high-quality and various optical fibers. Contact QSFPTEK to upgrade your cabling system. If you still have any questions, you can contact sale@qsfptek.com.