RF Electronics Chapter 7: RF Filters Page 259
2022, C. J. Kikkert, James Cook University, ISBN 978-0-6486803-9-0.
Figure 7.78 shows the final performance of the filters after optimisation. The hairpin filter
has a good symmetrical filter response and has good stopband attenuation. The direct-
coupled resonator filter has a better higher frequency attenuation, but a poorer lower
frequency attenuation. The interdigital filter has a poorer attenuation characteristic,
compared with the other filters. In particular, the attenuation near 1 GHz is only 50 dB.
The Combline filter has the worst close-in stopband attenuation of these filters. Combline
filters are used less often than interdigital filters.
Figure 7.78. Frequency response of three 5-resonator filters.
Figure 7.79. Harmonic response of the filters of figure 7.73.
RF Electronics: Design and Simulation
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