Basic knowledge of coaxial cable connector
Many standard connector formats, such as D-type connectors and many other multi-way connectors, consist of a series of pins that have parallel connections to each other. Coaxial cable connectors are usually very different and have some quite different characteristics.
1. Shield
Since radio frequency signals can be radiated, on the contrary, it is usually necessary to prevent foreign objects from being picked up. Therefore, RF connectors continue to shield coaxial cables as part of their nature.
2. Round
RF coaxial connectors need to maintain the coaxial characteristics of the cables used with them, so they are round. Therefore, they include a center pin for the inside of the coaxial cable, and then an internal external connection for the external conductor on the cable.
3. Characteristic impedance
The characteristic impedance of the feeder or coaxial cable is very important. Any mismatch will cause the power to be reflected back to the source. It is also important to match the characteristic impedance of the RF coaxial cable connector with the characteristic impedance of the cable. If it is not, it will introduce discontinuities and cause losses, but in practice, this may not affect most installations that use frequencies up to around 250 MHz. Most RF connectors are 50Ω, but for some domestic applications, other impedances such as 75Ω are available, as well as other impedances for applications such as data transmission.
4. Usually used for male and female coaxial cables for fixing
Unlike other types of connectors, the connector that provides signal or power is a female connector, because it is more protected and less likely to be short-circuited, and it is not necessarily suitable for RF connectors. The connectors on the leads here tend to be convex, while the connectors installed on the device are often concave, although in a few cases standard connector conventions can be used.
5. Cable type
Since different types of coaxial cables have different sizes, different types of coaxial connectors can be used to fit a given cable type. It is important to ensure that the correct RF connector variant is used with the relevant coaxial cable, otherwise the connector will be difficult to install, if it can do a reasonable job, even if it can connect the coaxial cable and the RF connector may not Satisfactory.
There are various connectors for RF applications. Impedance, frequency range, power handling, physical size and many other parameters (including cost) will determine the best type for a given application.
