zxcv2201
Member level 1
I conducted a simulation using the AFE + mixer structure.
(At this time, the mixer's RF and LO frequencies were the same)
In this case, I have one question.
The total gain of AFE and LNA is about 30dB, and NF is 4.6dB.
I checked NFdsb at DC, and I think it has a high value of 52dB due to DC noise.
As a result of the simulation, the desired result graph was obtained, but there is a question as to why the result is obtained properly despite the mixer's high noise figure.
In my personal opinion, I interpreted it as follows :
According to the noise figure equation, the NF of the mixer is divided by the gain of the front stage. Since the gain values of AFE and LNA are large, I think the result was achieved because the influence of the mixer's NF was reduced.
I wonder if this interpretation is correct.
(At this time, the mixer's RF and LO frequencies were the same)
In this case, I have one question.
The total gain of AFE and LNA is about 30dB, and NF is 4.6dB.
I checked NFdsb at DC, and I think it has a high value of 52dB due to DC noise.
As a result of the simulation, the desired result graph was obtained, but there is a question as to why the result is obtained properly despite the mixer's high noise figure.
In my personal opinion, I interpreted it as follows :
According to the noise figure equation, the NF of the mixer is divided by the gain of the front stage. Since the gain values of AFE and LNA are large, I think the result was achieved because the influence of the mixer's NF was reduced.
I wonder if this interpretation is correct.
