An RF connector is an electrical connector designed to work at radio frequencies in the multi-megahertz range. RF connectors are typically used with coaxial cables and are designed to maintain the shielding that the coaxial design offers. Better models also minimize the change in transmission line impedance at the connection. Mechanically they provide a fastening mechanism (thread, bayonet, braces, push pull) and springs for a low ohmic electric contact while sparing the gold surface thus allowing above 1000 reconnects and reducing the insertion force. Research activity in the area of radio-frequency (RF) circuit design has surged in the last decade in direct response to the enormous market demand for inexpensive, high data rate wireless transceivers.
Many coaxial connector types are available in the RF and microwave industry, each designed for a specific purpose and application. Much of the development of the smaller connectors that perform well into the GHz and millimeter wave range has been conducted by test equipment measurement companies. One of their considerations is the number of connect-disconnect cycles that a connector pair can withstand while still performing as expected.
The connectors can be arranged into three categories:
Primary Interconnects - widely used to interconnect RF equipment and components,
Less Common Interconnects - connectors that are used to interconnect RF equipment and components, but are less widely in use.
Connectors for Precision Measurement Systems - which, as the title implies, are usually found only interconnecting and mating to measurement apparatus such as spectrum and network analyzers. Radio Amateurs may run across precision measurement connectors when buying flea-market items because those items are useful in microwave interconnection even though they were originally intended for measurement systems.