IPD-Based Miniaturized Bandpass Filter Chip with Independently Controllable Transmission Zeros Using Lumped Elements

This paper presents a novel design of a compact, bandwidth-adjustable bandpass filter (BPF) using Integrated Passive Device (IPD) technology. The BPF adopts a symmetrical configuration of lumped elements, enabling independent control over transmission zeros and flexible adjustment of bandwidth. The filter's performance is validated through odd-even mode analysis and confirmed by both electromagnetic simulation and experimental measurements. The fabricated BPF chip achieves excellent performance with dimensions of 1.40 mm × 0.88 mm, featuring an insertion loss of 1.26 dB in the passband and a stop-band rejection exceeding 21.44 dB.