Abstract

A microstrip filter with cascaded Electric coupling trisection and magnetic coupling trisection is proposed. This study aims to create transmission zeros at both the side of the passband. Optimal performance is achieved by creating variable gaps in the resonators and providing open ended tuning stubs at appropriate locations. To demonstrate the concept a filter is realized and fabricated operating at 905 MHz with a pass band of 877 to 917 MHz (5%). The inherent disadvantage of wider roll off from the conventional filter is overcome by the introduction of stubs. Measured results are compared and found to be in good agreement with simulated results.

Keywords:

Bandpass filter, cascaded trisection, transmission zero,

References

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Competing interests

The authors have no competing interests.

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The authors have no competing interests.