wideband circulator two octaves?

[CopperCone]

Do these exist? I only find circulators with 1.5 octaves and isolators with two octaves.

I wanted a 3 port device that has a two octave bandwidth.

[rfeecs]

Probably not.
There are peripheral mode isolators that have an absorber built in as part of the structure and can be multi-octave, but they are isolators, not circulators.

From Wikipedia:
https://en.wikipedia.org/wiki/Isolator_(microwave)#Field_displacement

Field displacement[edit]
This type is superficially very similar to a resonance absorption isolator, but the magnetic biassing differs, and the energy from the backward travelling signal is absorbed in a resistive film or card on one face of the ferrite block rather than within the ferrite itself.

[MikeLogix]

There is a physical limitation to circulators that limits the bandwidth. What I mean is, the part is built with physical dimensions that dictate its frequency of operation. It is just not possible to exceed these limitations.
One possible 3 port device that you might look at is a directional coupler. Depending on your frequency you might find multiple octave bandwidth. Power level and directivity will be specs that you should look at when using couplers. Hope that helps ya.

[CopperCone]

I looked. What is the difference between the DC and the Circulator?

They seem similar (i.e. 4 port circular to DC).

Loss? Power Handling?

[CopperCone]

So I am guessing commercial NLJD use directional couplers instead of circulators (due to cost of multi octave ones which I found were unforgiving)?

Does anyone know?

That has a 20dB loss though, right? Compared to 0dB.