high power wilkinson power divider

[young.microwave.eng]

hi everyone
i'm looking to know the practical consideration for high power wilkinson power divider for S-band frequencies.the power is some number around 3KW.would you please help me finding that?
my main questions are?
Can I design it in microstrip or stripline format?
If yes what is the approperiate substrate?
what is the minimum lenght of microstrip or stripline to satisfy the amsulut maximum rating of substrate?

thanks in advance

 

[tony_lth]

You can use microstrip.
What is your power? You can use thick substrate, and use high-power-rating resistor.

 

[davenn]

You can use microstrip.
What is your power? You can use thick substrate, and use high-power-rating resistor.

he stated 3 kW ... that I would like to see on a microstrip!! I could imagine some serious smoke release
if everything wasnt just perfect

maybe some one knowledgeable can educate us all ...... Calling member Bigboss

Dave

 

[volker_muehlhaus]

Can I design it in microstrip or stripline format?

I have seen such designs in stripline, with machined aluminimum and air dielectric. The center conductor was mounted with teflon posts.

 

[BigBoss]

maybe some one knowledgeable can educate us all ...... Calling member Bigboss
Dave

I'm just learning buddy...

 

[tony_lth]

Sorry for ignore 3KW.
1. You can use waveguide Magic-T.
2. I guess 3KW is pulse power, what's your average power? 3KW peak power, that is 387V. For RO4000, the electric strength is 31KV/mm. Say you select Alumina substrate with 2mm, that is 200V/mm.

 

[young.microwave.eng]

hi guys
thanks for your replies
yes 3KW is the peak power.thanks for your point
I have limitation for volume of divider and I can not use wave guide construction as I'm working in S band and the dimension of wave guide will be big.
and about the reply of tony I have some question.I think 31kv/mm is for the breakdown of substrate.If the average current of microstrip is High,is there any other consideration?for example I have to find some thick material and find the 50 ohm or 70.7 ohm more wider than usual??

 

[tony_lth]

Yes, 31KV/mm is max rating.
Other limits:
1. Thermal: you can calculate the insertion loss of the divider, then you can get the thermal power. As davenn said, too hot maybe light.
2. VSWR: Any mismatch may cause damage at the component's pad, such as capacitors, input connector, output connectors etc.
3. Unbanlance: If one arm of the divider fails, then the divider will take half of the input power.