There is a wide array of methods of connecting RF circuits. The most common type are standardized connectors based on coaxial technology, typically just referred to as RF Connectors. Most RF connectors are coaxial connectors, as the other common type of RF interconnect, waveguides, are generally simply referred to as waveguides or flanges. There are also twisted pairs and other methods of RF interconnect for planar circuit boards (probes, custom fixtures etc.), but these are far less commonly used than coaxial connectors or waveguides.
Coaxial
Coaxial connectors are the basis for most connectorized module to connectorized module interconnect applications. Coaxial connectors are also used internally to some more complex systems and integrated modules due to ease of repair. Coaxial connectors are also the main types of RF connectors used in testing to high millimeter-wave frequencies. Beyond 100 GHz, waveguide interconnect becomes much more common as waveguides tend to exhibit less insertion loss through the flange interconnect and loss-per-unit-length along the interconnect path.
Printed Circuit Board
It is often necessary to transition from planar circuit board technologies, such as PCB, to a coaxial RF connector environment. One of the methods to do this is to use an End Launch Removable Connector, or a solder connector. Other methods include surface mount technology (SMT) solder or screw-mount (clamp) connectors. These are often available for the most common types of coaxial connector standards and push-connect standards, such as SMA, SMB, MCX, MMCX, BNC, 3.5 mm, 2.92 mm, 1.85 mm etc.
Terminal/Panel Mount/Bulkhead
In waveguide systems or inside conductive housings for RF circuits, there is often a need to transition from the inside of the housing to the outside through a terminal, panel mount, or bulkhead connector. These connectors may either have two coaxial connector heads, in the case of bulkhead connectors, or for terminal and Panel Mount Connectors may simply have a tap to the center conductor that can be used to connect directly to an RF circuit or internal coaxial cable.
Field Replaceable
There is a variation of a coaxial connector that includes field replaceable components, such as the center conductor. These field replaceable components are useful in applications where the contacts may be damaged or wear due to frequent cycling or extreme operational parameters. These types of connectors are called Field Replaceable Connectors and there are typically field replaceable variants of most common types of coaxial connectors.