How do Fiber Optic Cable Work?
In many ways, fiber optic media addresses the shortcomings associated with copper based media. Because fiber based media use light transmissions instead of electronic pulses, threats such as EMI, crosstalk, and attenuation become a nonissue. Fiber is well suited for the transfer of data, video, and voice transmissions. In addition, fiber-optic is the most secure of all cable media. Anyone trying to access data signals on a fiber-optic cable must physically tap into the media. Given the composition of the cable, this is a particularly difficult task.
Unfortunately, despite the advantages of fiber-based media over copper, it still does not enjoy the popularity of twisted-pair cabling. The moderately difficult installation and maintenance procedures of fiber often require skilled technicians with specialized tools. Furthermore, the cost of a fiber-based solution limits the number of organizations that can afford to implement it. Another sometimes hidden drawback of implementing a fiber solution is the cost of retrofitting existing network equipment. Fiber is incompatible with most electronic network equipment. This means that you have to purchase fiber-compatible network hardware.
Fiber optic cable itself is composed of a core glass fiber surrounded by cladding. An insulated covering then surrounds both of these within an outer protective sheath. Figure 3 shows the composition of a fiber optic cable.
Two types of fiber-optic cable are available: single and multimode fiber. In multimode fiber, many beams of light travel through the cable bouncing off of the cable walls. This strategy actually weakens the signal, reducing the length and speed the data signal can travel. Single-mode fiber uses a single direct beam of light, thus allowing for greater distances and increased transfer speeds. Some of the common types of fiber-optic cable include Outdoor Fiber Optic Cable and Indoor Fiber Optic Cable. Outdoor fiber optic cable is divided into outdoor unitube cale, outdoor stranded loose tube cable and outdoor Aerial/Figure 8 Cable.
Outdoor fiber optic cable is made to protect the optical fiber to operate safely in complicated outdoor environment. Most outdoor fiber cables are loose buffer design, with the strengthen member in the middle of the whole cable, the loose tubes surround the central strength member. Inside the loose tube there is waterproof gel filled, whole cable materials used and gels inside cable between the different components (not only inside loose tube) will help make the whole cable resist of water.
Stranded Loose Tube Cables are composed of several fibers together inside a small plastic tube, which are in turn wound around a central strength member and jacketed, providing a small, high fiber count cable. This type of cable is ideal for outside plant trunking applications, as it can be made with the loose tubes filled with gel or water absorbent powder to prevent harm to the fibers from water. It can be used in conduits, strung overhead or buried directly into the ground. Since the fibers have only a thin buffer coating, they must be carefully handled and protected to prevent damage.
Aerial figure 8 cable is a design that has high tensile strength and flexibility in a compact cable size. These cable provides excellent optical transmission and physical performance.
In the ever-increasing search for bandwidth that will keep pace with the demands of modern applications, fiber-optic cables are sure to play a key role.
