A New Compact Dual-Band Half-Mode Substrate Integrated Waveguide Bandpass Filter

A new compact dual-band filter is proposed by combining the half-mode substrate integrated waveguide (HMSIW) technique and the complementary split-ring resonator (CSRR) loading method. By adding the meander CSRRs with parasitic branches and stepped-impedance resonator CSRRs on the upper and lower metal surfaces of the HMSIW, respectively, two forward passbands below the cut-off frequency of the HMSIW are obtained. Research has been carried out in FR1 band of 5G. The simulation result shows that the proposed filter works at 2.6-2.78GHz and 3.76-3.91GHz, the return loss is less than -15.4dB, the insertion loss is less than 1.31dB and the size is only 0.242λ
g
× 0.122 λ
g
. Compared with some existing research results, The filter proposed has the benefits of compactness, low insertion loss easy integration and excellent sideband rejection.