A Bandpass Filter Integrated Single-Pole-Single-Throw Switch For Ku-band application

In this paper, a single-pole single-throw (SPST) filtering switch is designed utilizing PIN diodes for Ku-band application. The switch topology is based on a fourth-order bandpass filter, and a high frequency selectivity is accordingly achieved. For miniaturization, two dual-mode hybrid resonators are used. With the coupled topology, one transmission zero is generated on the both sides of the passband, contributing to an wide out-of-band suppression. To achieve strong off-state suppression, PIN diodes and lumped capacitors are loaded in series to form a resonant network. Under the on-state, the filter switch exhibits a bandpass response with a center frequency of 15.6 GHz, a bandwidth of $\mathbf{3. 5} \mathbf{~ G H z}$, and an insertion loss of 1.50 dB. Under the off-state, the circuit demonstrates a suppression level exceeding 34.07 dB, ensuring effective isolation.