Project #2 Band-Pass Filter

RF/Microwave Circuits I Course Project #2

Band-pass Filter Rahul Ekhande: Group 1

Rahul Ekhande

b) Schematic showing the filter circuit

c) Figure showing the layout in Momentum

Project #2 Band-Pass Filter

d) The plots comparing the circuit and EM simulation results.

Circuit Simulation S21 and S11

EM Simulation S21

e) The FOM values for the circuit results and the EM results.

.

FOM S21(at 1.9 GHz)/S21 at 2.45 GHz

CIRCUIT 35.38

EM 9.3

Project #2 Band-Pass Filter

• A photograph of the fabricated design :

• A graph that compares the measured and simulated (Momentum) S11 and S21

Measured response

Momentum response

Project #2 Band-Pass Filter

Design Summary:

Main aim was to have sharp roll off, so primary testing was on less Bandwidth. But the EM

simulation output was not reasonable for good FOM. Tried for 2% to 15% B.W. Final output is for 7%

B.W. With simple coupled line filter FOM was very less, so added the radial stubs to improve the cut-

off attenuation. Spacing between two coupled filter lines plays a vital role in output, less the spacing

more will the coupling but the spacing is restricted to minimum 0.4 mm. In the comparison for EM

Momentum and measured we can shift in output because of difference in the thickness of substrate.

To improve the attenuation at 2.45 GHz tuning and optimization was done.The filter was successfully

implemented for given cut off frequency (1.9 GHz) and Attenuation frequency (2.45 GHz). The

current density for different frequencies is shown below:

at 1 GHz

at 1.9 GHz

at 4 GHz