How to choose an RF Circulators
An RF circulator is a three-port ferromagnetic devices used to regulate the signal flow within a circuit. To illustrate, think of a device with 3 ports A, B and C – a signal that enters port A will be directed to port B, any incident/reflecting signal from port B will be directed to port C and any incident/reflected signal will be directed to port A.
The key specifications to look for in an rf or microwave circulator are:
Frequency (MHz): This is the frequency range over which the rf circulator can operate with while providing a constant level of isolation and minimal insertion loss.
Isolation (dB): This is a measure of signal levels at the adjacent ports of the rf circulator. It is measured in decibel (dB).
Insertion Loss (dB): This is the measure of loss in the transmitted signal from one port to the next. This is measured in decibel (dB).
Power (W): This is the level of power that the isolator or circulator can handle while maintaining the isolation and insertion loss required for the required application.
Package Type: These are ferromagnetic devices and are packaged in various form factors – Drop-In, Surface mount, modules with connectors etc.