فهرست نشریات علمی دسترسی آزاد ایران

Mixed Electric and Magnetic Cross Coupling (MEMCC) filters can generate more out-of-band Transmission Zeros (TZs) compared to traditional coupling methods. This results in good out-of-band suppression due to the presence of Mixed Electric and Magnetic Coupling (MEMC) on the cross-coupling path. They are suitable for modern wireless communication systems that require high selectivity. This paper proposes a fourth-order MEMCC wideband Bandpass Filter (BPF) centered at 6.8 GHz with a 22.8% Fractional Bandwidth (FBW). In addition, the odd-even mode method is used to determine resonance modes, and the coupling matrix has been proposed to investigate the MEMC further. Four TZs are positioned on either side of the passband. The suppression can reach -30 dB at 2.35f0 (center frequency). At the same time, the filter uses a folded Step Impedance Resonator (SIR) structure, with a physical circuit size of 7.45 mm × 5.725 mm. The electrical length size is only 0.28 λg × 0.22 λg (waveguide wavelength), achieving miniaturization of the filter. Compared to the state-of-the-art filters, the MEMCC filter proposed in this paper has innovations and advantages in terms of the number of out-of-band TZs, circuit size, and structural topology.