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This paper presents for the first time a fully electronically reconfigurable waveguide filter tunable in bandwidth and center frequency based on liquid crystal (LC) technology. A continuously reconfigurable two pole bandpass filter is designed and characterized in the Ka-band at <inline-formula><tex-math notation="LaTeX">$30 \,\mathrm{GHz}$</tex-math></inline-formula>. To be able to tune both center frequency and bandwidth independently, the resonators and coupling structures are filled with LC as tunable material. Hence, the filter&#x2019;s center frequency and coupling strengths can be tuned and, furthermore, tuning with constant filter characteristic is possible. To tune the LC, a novel two-layer electrode design for waveguide structures is presented, which is simple to integrate and provides a high tuning efficiency with low insertion loss. By applying different bias configurations, the LC&#x2019;s effective permittivity can be varied, and therefore, also the resonators&#x2019; electrical lengths. The presented two pole filter can adapt its center frequency from <inline-formula><tex-math notation="LaTeX">$29.8 \,\mathrm{GHz}\,{\rm to}\, 30.7 \,\mathrm{GHz}$</tex-math></inline-formula> with a maximum <inline-formula><tex-math notation="LaTeX">$3 \,{\rm dB}$</tex-math></inline-formula> bandwidth variation from <inline-formula><tex-math notation="LaTeX">$660 \,\mathrm{MHz}\,{\rm to}\, 870 \,\mathrm{MHz}$</tex-math></inline-formula>. The measurements are carried out with bias voltages up to <inline-formula><tex-math notation="LaTeX">$\pm$</tex-math></inline-formula><inline-formula><tex-math notation="LaTeX">$250 \,\mathrm{V}$</tex-math></inline-formula>.