Hello evry one there. i have been trying to design a bandpass filter for the 300Mhz-1Ghz frequency range. first i designed one which passes low frequencies like from 65mHz to about 560kHz...thereafter i changed the values of the resistors and capacitors to get my pass band to be close to 300Mhz to 1GHz, but it aint working at all.im doing all this in multisim. since the two cut off frequencies are known, the equations below helped get the resistor and capacitor value. i set one and found the other
f(lower )= 1/(2*pi*R4*C1)
f(lower )=300MHz. i set my C1=1pF and it yielded, R4=530 ohms
and
f(upper)= 1/(2*pi*R2*C2)
f(upper )=1GHz. i set my C2=1pF and it yielded, R2=160 ohms....from this it seems the frequencies i want in the pass band are actually 2wards the end of the pass band and strictly the 1GHz is outside..how can i have them well within the pass band and also with a gain >=0 attached is my circuit
also if u look at the pass band gain it's at -54dB, how can i increase it
need some advice hea
f(lower )= 1/(2*pi*R4*C1)
f(lower )=300MHz. i set my C1=1pF and it yielded, R4=530 ohms
and
f(upper)= 1/(2*pi*R2*C2)
f(upper )=1GHz. i set my C2=1pF and it yielded, R2=160 ohms....from this it seems the frequencies i want in the pass band are actually 2wards the end of the pass band and strictly the 1GHz is outside..how can i have them well within the pass band and also with a gain >=0 attached is my circuit
also if u look at the pass band gain it's at -54dB, how can i increase it
need some advice hea
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