langer coupler wideband
The peak power level over 150W.
The ususal method for this bandwidth is to use a multiple finger Lange coupler.
Hi,
It is a large size even using a multiple finger Lange coupler,
a bended caxial coupler may be ok.
Dear friend,
I have been using the stuff from Sage Microwave. Take a look on their web site:
http://www.sagelabs.com/components/wirepac.html
Good luck
Here is a calculator for the Sage products.
For a directional coupler (at least 20dB i think) you could try a short coupler. I mean you could design the DC in a higher band (lets suppose 1GHz) to have lets say a coupling of 5dB and then work in your band where you have a slope in coupling. Then you can compensate the slope with a low pass filter
hoping this can help you
I have seen a technique where the printed Lange Coupler is replaced with chips and wire to reduce size at low frequencies. I will see if I can did up the article, but in the mean time maybe you can figure out what the values are by transforming the lines into the equivalent caps and inductors.
It is quite common to make directional couplers for the TV band freqs (100 - 800 MHz), with a 2 hole ferrite. There are a lot of literature about it. The only real drawback is the limited (max 20 dB) isolation.
g579
You might want to try Odyseus's RF & Micowave Theory site at
http://www.odyseus.nildram.co.uk/. He has some designs for couplers with chips and wires.