Additively Manufactured Multi-Layer Bandpass Filter Based on Vertically Integrated Composite Right and Left Handed Resonator

This paper proposed a miniaturised multi-layer composite right/left-handed (CRLH) resonator. The odd- and even-mode circuit analysis method is presented to explain the resonance properties of the three-dimension (3D) CRLH resonator. Based on the CRLH resonator, a bandpass filter (BPF) with wide bandwidth, low-loss, and compact size is proposed. A fully-integrated additive manufacturing (AM) approach is introduced to fabricate the proposed BPF. Finally, the proposed compact BPF is designed at 8.3 GHz with a bandwidth of 72.3%, a low insertion loss of 0.51 dB, and a compact size of 5.8mm × 2.1 mm × 0.89 mm (0.269λg × 0.097λg× 0.041λg), which is suitable for circuit-in-package applications