A FOURTH-ORDER SIW BANDPASS FILTER WITH OPTIMIZED PASSBAND PERFORMANCE FOR MILLIMETER-WAVE APPLICATIONS

Tóm tắt

This paper presents the design of a four-order substrate integrated waveguide (SIW) bandpass filter optimized for millimeter-wave wireless applications. SIW technology balances loss, cost, and integration capabilities while achieving high selectivity and a compact form factor in RF/Microwave filter design. Since SIW primarily operates in the dominant TE₁₀ mode, the electric field E has a maximum value located on the vertical central plane and along the propagation direction. Therefore, the central plane can be considered an equivalent magnetic wall. The proposed filter is composed of four SIW resonators connected in series. The simulated results show that the fourth-order SIW filter has a center frequency of 26 GHz with 3 dB bandwidth of about 4.67 GHz. The achieved minimum insertion loss in the passband is 1.1 dB, and return loss is better than 20 dB. The passband ripple is significant reduced to below 1dB, while the out-band rejection is better than 20 dB from 22 to 23.1 GHz which improved the selectivity of the filter. This filter is suitable for millimeter-wave wireless systems such as 5G, automotive radar, and satellite communication due to its high selectivity, low loss, and compact size