how to improve the VSWR check accuracy of the PA

[springf2000]

how to improve vswr

dear sir :
i use one RCP2150m30 as the VSWR check device,this is a dircetional coupler,but i find the check result is not very accuracy,how to improve it?

 

[brmadhukar]

vswr check

Hi,
You expect variation at the output of PA many times. Is the gain stable?
Do check the quality of interconnections? I donto think that the DC has a problem (I assume frequency is OK).
brmadhukar

 

[vfone]

This coupler is dedicated mainly for PCS applications (1900MHz). At this frequency an important factor that will affect VSWR reading, is the layout and a proper terminations at each port of the coupler.

 

[borich_03]

May be your problem is not a coupler?
For good VSWR check accuracy of the PA you need to have a good analog part of the VSWR check system, also. Check: detector, amplifier, reference source and other parts.