A circulator is a specialized RF and microwave device, typically using ferrite materials and magnetic fields, that directs signal flow sequentially from one port to the next. If a signal enters port one, it only exits port two; a signal entering port two only exits port three. They are heavily used in radar and communication systems to allow a transmitter and receiver to share a single antenna without destroying the sensitive receiving electronics.
Check the isolation on that circulator, because the transmitter power is leaking back into the receiver path and causing distortion.
A circulator can be converted into an isolator by terminating one of its ports with a matched dummy load, ensuring any reflected power is absorbed rather than returning to the source.
Also heard as
- RF circulator
- microwave circulator
Related terms
Dummy load
A resistive device used to absorb power from a transmitter or amplifier during testing.
Signal processing
The mathematical manipulation of physical data streams to filter, compress, or extract information.
Passive
An electronic component that does not require external power to operate and cannot provide signal gain.