See

 

See total noise 9uV !

 

See
View attachment 127940 View attachment 127941

Dear Sir,
Thank you for taking the time for me.
Actually, It's hard for me to understand the circuit, please show me how to calculate the gain of the amplification in the circuit above.
Is it possible to amplify and reject noise in my case? so sorry for my bad.

Thank you again

 

You might try one of these design tools to help with your filter calculations.

 

See
View attachment 127940 View attachment 127941

Beautiful!

 

The circuit is a cascaded connection of a high-pass filter and a low-pass filter.
Each filter is made on an amplifier with a single gain according to the Sallen-Kay scheme.
Nominals are chosen without using theory and corresponding formulas.
Additional load resistors transfer the output stage to class "A".
The widely used spice models for the LM358 do not reflect the true operation mode of the output stage in class "B".
The results of the simulation do not coincide with reality. So I made my own, transistor model.
The transmission coefficient at the average frequency is 0.86. At 2kHz 0.72, at 3.5kHz 0.7.
You can optimize the circuit and achieve a transmission gain at a mid-frequency of 1.
But I decided that it was not bad and so.
Noise levels of the amplifier turned out to be quite good.
In reality, the induced interference is much larger in magnitude.

 

The circuit is a cascaded connection of a high-pass filter and a low-pass filter.
Each filter is made on an amplifier with a single gain according to the Sallen-Kay scheme.
Nominals are chosen without using theory and corresponding formulas.
Additional load resistors transfer the output stage to class "A".
The widely used spice models for the LM358 do not reflect the true operation mode of the output stage in class "B".
The results of the simulation do not coincide with reality. So I made my own, transistor model.
The transmission coefficient at the average frequency is 0.86. At 2kHz 0.72, at 3.5kHz 0.7.
You can optimize the circuit and achieve a transmission gain at a mid-frequency of 1.
But I decided that it was not bad and so.
Noise levels of the amplifier turned out to be quite good.
In reality, the induced interference is much larger in magnitude.
View attachment 127979 View attachment 127980

Dear Sir,
Thank you so much for the reply.
Are the capacitors used in your scheme non-polarized or polarized capacitors? I have tried simulating your circuit with non-polarized capacitors but I got nothing at the output.
Could you share with me something about "your own transistor model" please?

Thank you.

 

used non-polarized capacitors. Polarized capacitors of such a small capacity you will not find!