Isolators and Circulators Facilitating Smooth Communication

• Raditek offers the widest range and best performance Stripline, Microstrip, Coaxial and Waveguide isolators and Circulators in the world with an extremely aggressive pricing structure. Our ferrites are the best anywhere

• A circulator is a three port device. It is essentially a passive device; it can however exhibit some characteristics that make it almost behave as if it were active. An isolator is a two port device having an input and an output; it is simply a circulator whose third port has been terminated.

Isolators and Circulators provide unique transmission paths, allowing RF energy to pass in one direction with little (insertion) loss, but with high loss (isolation) in the other direction. They can exist as Stripline, Coaxial, Microstrip, or Waveguide types, and can be rated for powers from milliwatts to Megawatts.

• Raditek can provide superb stripline isolators to 18GHz, Microstrip to 60GHz, Waveguide over 100 GHz. Coaxial (25MHz to 50GHz): a wide range of narrow band to multi-octave, SMA, N, K, 2.4 connectors Cryogenic models: 0.01-4 Degree Kelvin, 4-77 Degree Kelvin, SMA, N, K, 2.4 connectors Wide Band: Octave, Octave+ and Peripheral mode Isolators

• A typical use of a circulator would be as a duplexer, connecting a transmitter to Port 1, antenna to port 2 and receiver to port 3. This provides simultaneous transmission and reception of signals.

• A very common use for isolators is at the output of a power amplifier. Forward power is passed with a minimal insertion loss. Reverse power resulting from a Mismatch or disconnect at the output (ieremoving the connection to antenna), will (with no isolator installed) flow back to the output FET/LDMOS/ GaN device etc. and likely damage or destroy it/them. With the isolator installed, any reflected power will flow into the isolator’s load and be safely dissipated as heat (as long as the load is rated to handle the power, and is properly heat sunk, so that the load temperature stays <100°C).

• Typical S parameters could be 0.25dB insertion loss, 22dB isolation and VSWR on the ports of 1.2:1 over a 5% percentage bandwidth. Size increases for greater bandwidths.

• The Raditek isolators and circulators are believed to have the best performance inthe marketplace, within constraints and compromises of physical size, power, and RF performance. Examples of all of these can be found on our web site at