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A new compact microstrip dual-band bandpass filter (BPF) based on multi-mode λ/4 stepped-impedance resonators (SIRs) with separate coupling paths is investigated. The dual-band BPF with a secondorder bandpass response is composed of only two λ/4 SIRs, resulting in a small circuit size. A coupling gap and a common short-ended stub between the two coupled SIRs are used to create the electric and magnetic couplings with separate coupling paths. The bandwidths of the dual-band BPF can be well controlled by adjusting the coupling strengths of the two coupling paths. Thus, a greater design flexibility for the dual-band BPF can be obtained. For demonstration, a secondorder dual-band BPF with a compact size of 0.14 λg × 0.16 λg has been designed and fabricated. A good agreement is achieved between simulation and measurement. [ABSTRACT FROM AUTHOR]