Multifunctional Bandpass Filter/Displacement Sensor Component

This paper presents the design and realization of a multifunctional bandpass-filter/displacement-sensor using an edge-coupled microstrip bandpass filter loaded by pair split ring resonators (SRRs). It is shown that while structure acts as at its operating frequency, phase reflection coefficient from movable loading resonator resonance frequency can be used for displacement sensing. With this aim, to avoid any interference with functionality, SRRs chosen within stopband filter, where all input signal reflected back port. Therefore, moving does not have adverse effect on filtering performance. To validate concept, fifth-order Chebyshev feed line designed numerical evaluation proposed provided. The component also validated through fabrication measurement. has sensitivity 8°/mm SRRs. However, increased scaling resonate higher upper filter.