Fiber optic cable and coaxial cable are two different products. Simply put, the biggest difference between coaxial and optical cables is transmission speed. Fiber optic cable is significantly faster than coaxial cable, and of course, it is currently the fastest transmission medium. The following article introduces fiber optic and coaxial cables, and the specific differences between them.
Introduction to Fiber Optic and Coaxial Cables
Optical fiber cable is a type of communications cable consisting of two or more glass or plastic optical fiber cores, enclosed in a protective sheath and covered by a plastic PVC outer casing. Signals along the inner fibers are typically transmitted using infrared light.
Optical fiber cable, short for fiber optic cable, is a medium for transmitting light signals. It consists of a core, a cladding, and an outer protective layer for strength. The core is made of cylindrical silica doped with materials such as germanium and phosphorus. The outer cladding, made of pure silica, refracts the light signal into the core. Optical fiber is categorized as single-mode and multi-mode. Single-mode provides only one optical path, while multi-mode provides multiple optical paths. Single-mode fiber offers higher capacity but is more expensive. Currently, the core-to-cladding dimensions of single-mode fiber are approximately 8.3μm/125μm, while the commonly used core-to-cladding dimensions of multi-mode fiber are 62.5μm/125μm. Optical fiber is limited to unidirectional transmission; for bidirectional communication, it should be used in pairs. Domestic optical fiber service speeds have already reached 100Mbps, and service providers have stated that they will eventually increase this figure to 1Gbps to 10Gbps.
In real-world applications, only cable television still uses coaxial cable. However, with continued development, this is gradually being replaced. Other networks generally use optical fiber and twisted-pair cables, especially for long-distance transmission, where optical fiber is the optimal choice. Therefore, we should learn more about optical fiber. Keeping pace with the times certainly has its unique advantages, making it worthwhile to understand and learn about.
Coaxial cable refers to a cable with two concentric conductors, with the conductors and shielding sharing a common axis. The most common coaxial cable consists of a copper conductor separated by insulating material. Surrounding the inner insulating layer is another ring-shaped conductor and its insulator, and the entire cable is then sheathed in polyvinyl chloride or Teflon.
Coaxial cable consists of a hollow metal tube (outer conductor) and a rigid copper wire (inner conductor). The inner conductor is located in the center of the tube, and a polyethylene plastic spacer is used to insulate the inner and outer conductors. There are three types of coaxial cables used in local area networks: 75Ω, 50Ω, and 93Ω. RG59 75Ω cable is the standard cable for community antenna television (CATV) systems. It is commonly used to transmit analog signals generated by frequency division multiplexing (FDM) at frequencies up to 300-400 MHz, known as broadband transmission. It can also be used to transmit digital signals. 50Ω coaxial cable comes in two types: thick (RG-8 or RG-11) and thin (RG-58). Thick cables have better anti-interference properties and can transmit over longer distances, while thin cables are cheaper and can transmit over shorter distances. Their transmission rate is generally 10 Mbps, making them suitable for networks. RG-62 93Ω cable is the coaxial cable used in Arcnet networks and is typically only suitable for baseband transmission, with a transmission rate of 2 to 20 Mbps.
The Difference Between Fiber Optic and Coaxial Cable
Simply put, the biggest difference between coaxial and optical cables lies in transmission speed. Optical cables are significantly faster than coaxial cables, and of course, optical cables are currently the fastest transmission medium.
1. They differ in material: coaxial cables use metal, while optical cables use glass fibers.
2. They differ in transmission mode: coaxial cables use electromagnetic waves, while optical cables use light.
3. They differ in transmission distance, transmission protocols, and overall physical concepts.
In real-world applications, only cable television still uses coaxial cable, but with its continued development, it is gradually being replaced. Other networks generally use optical fiber and twisted pair cables, especially for long-distance transmission, where optical fiber is the optimal choice. Therefore, we should learn more about optical fiber. It has its own unique advantages and is worth learning about.
