Low-Loss Flexible Filter Based on Compact Double Interdigital Coupling SIR With TPV Technology for Bendable Wireless Communications
Le Liu, Fengjuan Wang, Xiangkun Yin, Ming Xu, Yuan Yang, Ningmei Yu, Yao Li, Yan Li
Abstract
This letter presents a compact, low-loss flexible filter based on a double-interdigital coupling stepped-impedance resonator (SIR) and through-polyimide via (TPV) technology. With a fractional bandwidth (FBW) of 12.5% at 2.5 GHz, the filter achieves a low insertion loss of 1.8 dB in the flat state and only 1.95 dB under bending. Its electrical performance remains highly stable under deformation, while the structure attains a 40% size reduction over the state-of-the-art designs, offering a promising solution for wearable wireless systems demanding flexibility and spectral selectivity.
Topics & Concepts
WirelessBandwidth (computing)Filter (signal processing)ResonatorFlexibility (engineering)Coupling (piping)Electronic filterElectronic engineeringBand-pass filterComputer scienceFractional bandwidthMaterials scienceInsertion lossReduction (mathematics)Electrical engineeringWearable computerFiltering theoryOptoelectronicsActive filterInductive couplingAcousticsEngineeringFilter designPhysicsBluetoothTelecommunicationsWearable technologyMicrowave Engineering and WaveguidesAntenna Design and AnalysisFull-Duplex Wireless Communications