1 Introduction
2 Methodology of the proposed resonator
2.1 Analysis of the proposed resonator
2.2 The source-load coupling technique
3 Results and discussion
3.1 Structure of the dual-band BPF
3.2 Simulated and measured results of the dual-band BPF
3.3 Comparison between the existing filters and the proposed filter
Center frequency (GHz) | Return loss (dB) | Insertion loss (dB) | 3-dB relative bandwidth (%) | Transmission zeros | |
---|---|---|---|---|---|
Filter in [2] | 2.4/5.8 | 20/25 | 1.4/3.2 | 12/− | 2 |
Filter in [3] | 2.4/5.16 | ≥ 12 | 0.6/1.4 | 13.7/6.3 | 2 |
Filter in [5] | 1.7/2.15 | 15/18 | 3.5/4.8 | 6.35/4.6 | 4 |
Filter in this paper | 1.25/2.0 | 18/27 | 0.8/0.5 | 7.8/10.6 | 4 |