suggest to get lowest posible NF for an LNA

[chacha]

LNA

Can anybody suggest to get lowest posible NF for an LNA??
Say i want an NF of 1.5dB, in what way i can try to achieve this in LNA design??

Thanks.

 

[fanshuo]

LNA

what kind of technology are we talking about?CMOS or bipolar or what?

I am not sure but I think if you burn a lot of power CS degenerated LNA is capable for 1.5dB NF

 

[chacha]

Re: LNA

it is tsmc18rf.
iam constrained by power limitation of 6mA.
the quality factor of Lg doesn't seem to be affecting the NF(from simulatons).

 

[vfone]

Re: LNA

While ago LNA with very low noise figure can get only in GaAs (FET or HEMT):
https://www.mitsubishichips.com/Global/products/hf/sm_02.html

But now they are available in other processes including SiGe:
**broken link removed**

 

[fanshuo]

LNA

the quality factor of Lg should influence the noise factor F,right
F=1+Rg/Rs+gama*gdo*Rs(f0/ft)^2
Rg,Rs is the parasitic resistance of the gate and source inductor
gdo is the transconductance when Vds=0,f0 is the working frequency while ft is the cut off frequency
gama is the noise coefficient ,about 1 for 0.18um
then you can calculate

 

[mitrobge]

Re: LNA

How can you measure gd0?