RF circulators are used in a variety of RF circuit design applications. Typically they tend to be used at microwave frequencies, hence they are often referred to as microwave circulators. RF circulators are used as duplexers in many RF applications to allow for simultaneous transmit and receive functions, and they are used in a wide range of RF design applications, including radar systems and a va...

Engineering deep dive · Ports, functions, specs, and selection traps RF Isolator and Circulator are two of the most misunderstood passive components in microwave engineering. The core difference comes down to ports and function. An Isolator is essentially a three‑port Circulator with its third port terminated into a matched load. A Circulator is a non‑reciprocal signal router — it directs signals ...

A circulator's isolation fails to hold 20dB over a wide temperature range because the ferrite's saturation magnetization (4πMs) changes with temperature. This shifts the device's operating frequency and impedance match. A circulator rated at 20dB isolation at room temperature can drop to 15dB or lower at -40°C or +85°C. This is not a design flaw — it is the physical nature of ferrite materials. Th...