A koaksial kabel("koaks" in English) is a cable composed of two koaksial, mutually insulated cylindrical metal conductors to form a basic unit (koaksial pair), vəthen a single or multiple koaksial pairs. It has been used to transmit data vəvideo signals for a long time.
It is one of the first media to support 10BASE2 və10BASE5 Ethernet, which can achieve 10 Mb/s transmission up to 185 meters or 500 meters, respectively. The term "koaksial" means that the central conductor of the cable vəits shield have the same axis or center point. Some koaksial kabels may have multiple shielding layers, such as a four-shielded koaksial kabel, which contains two layers of shielding, vəeach layer of shielding is composed of aluminum foil wrapped with wire mesh. The shielding characteristics of koaksial kabel make it have strong anti-electromagnetic interference ability vəcan transmit high-frequency signals over long distances. There are many different types of main types of koaksial kabels that support a wide range of professional applications, such as satellite communications, industrial, military vəmarine applications. The three most common types of non-industrial koaksial kabels are RG6, RG11vəRG59, bunlardanRG6ən çox istifadə olunurCCTV vəCATVkorporativ mühitlərdə tətbiqetmə. Orta dirijorRG11daha qalındırRG6, which means that its insertion loss is lower vəthe signal transmission distance is longer.
Ancaq daha qalındırRG11 kabelləri are more costly vəvery difficult to bend, which makes them unsuitable for deployment in internal applications, but more suitable for long-distance outdoor installations or straight backbone links. RG59daha çevikdirRG6, but its loss is higher. It is rarely used in other applications except for low-bandwidth, low-frequency analog video applications (rear-view cameras in automobiles) with short distances vəlimited wiring space. Koaksial kabellər also have different impedances-usually 50, 75, və93 Ω. 50Ω koaksial kabels have high power handling capabilities vəare mainly used in radio transmitters such as amateur radio equipment, civil bvəradio (CB) vəwalkie-talkies. 75 Ω cables can maintain signal strength well vəare mainly used to connect various types of receiving equipment, such as cable television (CATV) receivers, high-definition televisions vədigital video recorders. 93 Ω Cox kabel was used in IBM mainframe networks in the 1970s vəearly 1980s, with very few applications vəexpensive. Although the 75 Ω koaksial kabel impedance is most commonly encountered in most applications today, it is important to note that all components in the koaksial kabel system should have the same impedance to avoid possible signal loss vəsignal loss at the connection point. Internal reflections that reduce video quality. The digital signal 3 (DS3) signal used in the central office (also known as T3 line) transmission service also uses koaksial kabels, including 75 Ω 735 type və734 type. The 735 type cable has a coverage distance of 69 meters, while the 734 type cable has a coverage distance of 137 meters.RG6 kabeliDS3 siqnallarını ötürmək üçün də istifadə edilə bilər, lakin əhatə məsafəsi daha qısadır.