An SPDT-Switch-Enabled Dual-Band Millimeter- Wave Bandpass Filter for RFFE Applications

In this paper, a dual band millimeter wave bandpass filter using MEMS single-pole double-throw (SPDT) switch is proposed. The dual band filter is able to achieve a change in center frequency and band width (BW). The filter can be applied to the RF front end (RFFE), and make it simpler in structure. The first passband is from 76.8GHz to 79.2GHz, and the insertion loss (IL) is $-1.72 \mathrm{~dB} \text{@} 78 \mathrm{GHz}$. The second passband is from 118.2GHz to 121.8 GHz, and the IL is $-4.79 \mathrm{~dB} \text{@} 120 \mathrm{GHz}$. The pull in voltage of the MEMS SPDT switch is $8 \mathrm{~V}$. The function of switching the passband and center frequency is realized by applying the pull-in voltage on the MEMS-based SPDT switch.