**REQ: coupler with different power in near frequencies

[mamali]

Anyone have any idea about a coupler wich should couple 2 signals, one in 1240MHz with 50KHz BW, and another in 1252 MHz with 16MHz BW. signals have different power, and the coupler should be as compact as possible, and should be a microstrip type.
I think a filter should be design for each signal to force each input port to not sea the other; by the way, the unequal power is still a problem, and the filters needs a lot of space; please let me know about any ideas,
wishes,
Mat

 

[vfone]

What about this idea. Having high directivity can handle different power levels.
http://amsacta.cib.unibo.it/archive/00000405/01/Eug_p126.pdf

 

[mamali]

What about this idea. Having high directivity can handle different power levels.
h**p://amsacta.cib.unibo.it/archive/00000405/01/Eug_p126.pdf

dear vfone, tnx, but unfortunately the link is not available.

the main problem is that I have one signal in 1.24GHz with 50KHz bandwidth, and another signal in 1.252MHz with 16MHz bandwidth (you see they are so close together), do you think that combining these signals couse problems (for example harmonics and so on), and should i use filters befor combining? (becouse narrow filters in such band is hard and expensive and needs a lot of space ) by the way, is there any other combiner than wilkinson vailable? did you guys ever tried directional couplers as power combiners? please share any idea.

tnx, Mat

 

[vfone]

The link to the document works perfect (replace ** with tt )
A coupler can work as a combiner.
A coupler is not a non-linear device, so will not generate any extra harmonics.

You can use also a Wilkinson
**broken link removed**

or a Rat-race
**broken link removed**

 

[mamali]

dear vfone,
tnx, i do know about the stars, but it semms our network had some problems; anyway, as both of us know well that the directional couplers can be used as power combiners, and knowing that in all directional couplers there is a phase difference between two outputs, so for example we have (V1+V2) in port 1 and (V1-V2) in port two; my question here is could any directional coupler used as a power combiner for two different signals with different powers (even if they are close together) with a little loss? as i know, we should dissipate half of the output power into some load, and it just isolate the other ports from each other. do you or othger guys know a better way to have just a power combiner for two different signals with different powers, with little loss (say, 1dB)?
tnx in advance,
Mat