Return loss vs Gain level

[cjron]

I am working on an amplifier(microwave) circuit and i find that return loss looks awful (nearly close to zero) that's very close to being short. i can add on a little more solder at the input signal connector on my pcb that brings relatively higher return loss but i have to compensate the gain in few dB's (say like 2-3dB)..what is the best way of matching this circuit??

 

[dick_freebird]

Zero return loss is ideal. You want power absorbed (usefully)
at the driven input. Any power returned, is a detractor to
forward gain, net.

Why do you call near-zero return loss "awful"? That's the
first time I've heard anyone wanting more losses.

 

[D.A.(Tony)Stewart]

The measure of good performance is good attenuation on the input reflection or in other words high Return Loss. Since it is loss a positive number is used. RL=15dB is generally considered minimum acceptable for simple circuits.

Impedance is geometric ratio of conductor width to gap to nearest grounds. Uniformity is key and matching impedances over the range of interest.

Details required on schematic, part specs and layout to understand your issue. Photo's schematic etc.

Insertion Loss and Return Loss can both be affected by common changes, but understanding how each part contributes and how to test it , is a learned skill.

 

[cjron]

lol!! I dont want losses in my circuit neither..it was my bad that i forgot to mention that zero return loss means the output on my network analyzer is closer to 0dB reference..will upload the pic in a while