Need Help with band pass filters, Want to calculate the component values

[saeedu]

Hi

I am doing RF Power Amplifier for my project, I am trying to calculate the capacitance and Inductance I was hoping if someone could help me out.



Please avoid the values provide in the attachment.

Frequency range from 1Ghz to 8Ghz, with minimum BW of 0.5GHz
I want to start from scratch to calculate C2, C1 and L3. C2 Looks like a coupling Capacitor, therefore I used a low impedance value to calculate c2, However I don't think I am following the right steps, How will I go on to calculate C2, C1 and L3?

 

[Audioguru]

You do not have a bandpass circuit. C1 and C2 in series short the highest frequencies of the input signal and cut its level in half. The inductor also cuts high frequencies.

Here is a simple bandpass filter, its load affects its Q:

 

[saeedu]

You do not have a bandpass circuit. C1 and C2 in series short the highest frequencies of the input signal and cut its level in half. The inductor also cuts high frequencies.

Here is a simple bandpass filter, its load affects its Q:

Hi

Thanks for pointing that out, how will I proceed in calculating the Capacitance and Inductance?

 

[saeedu]

Also, when you say cut the highest frequencies in half. do you mean cutting the frequency in half? because through out the circuit it displays the same frequency as the input.

 

[Audioguru]

Thanks for pointing that out, how will I proceed in calculating the Capacitance and Inductance?

Look for LC Circuit in google and you will find this article: https://en.wikipedia.org/wiki/LC_circuit

Also, when you say cut the highest frequencies in half. do you mean cutting the frequency in half?

No.
Your two capacitors have an extremely low value (I have never heard of a capacitance so small, the capacitance between two bees that are 10m apart?) so they affect only the highest frequencies.
Since the capacitors are in series then they are an AC voltage divider which cuts the high frequency signal amplitude in half. Capacitors cannot divide a frequency.