Abstract |
This paper presents new microstrip bandpass filter design topologies that
consist of dual edge-coupled resonators constructed in the form of Moore fractal
geometries of second and third iteration levels. The space-filling property for
proposed fractal filters has found to produce reduced size shapes in accordance
with sequential iteration levels. These filters have been prepared for ISM band
applications at a centre frequency of 2.4 GHz using a substrate with a
dielectric coefficient of 10.8, dielectric thickness of 1.27 mm and
metallisation thickness of 35 µm. The output responses of each fractal bandpass
filter have been determined by a full-wave-based electromagnetic simulator
Sonnet software package. Simulated and experimental results are approximately
compatible with each other. These responses clarify that these fractal filters
have good transmission and return loss characteristics with blocked higher
harmonics in out-of-band regions. |