Design of periodically elevated groundplane SSS band-pass filter with suppressed second harmonic.

Using periodically elevated groundplane along the coupled line sections in the lower cavity of suspended substrate stripline (SSS), a parallel-coupled line band-pass filter having suppressed harmonic at 2f0 has been designed. Even and odd mode phase velocities in each coupled line section at 2f0 have been equalised by using the right number of periodic grounding cells with proper dimensions. Based on this equalisation technique, a filter at 2.4 GHz has been designed and fabricated to prove the concept. [ABSTRACT FROM AUTHOR]