Design and realization of broadband microwave absorbers by honeycomb integrated with screen-printed resistive films in the core holes

Abstract This paper presents a novel method for fabrication of honeycomb absorbers by assembling step cylindrical resistive films into the honeycomb holes. The process begins by creating a conductive step resistive film through screen printing. Next, this resistive film is wrapped around a cylindrical foam to form a step cylindrical resistive. Finally, the cylindrical resistive film is integrated into honeycomb structures, resulting in a honeycomb-integrated microwave absorber with step cylindrical resistive film. Excellent impedance matching and low reflection are achieved by controlling the square resistance of the resistive film to provide a step impedance transition between air and metal in the microwave broadband. A broadband absorber was developed by honeycomb integrated step cylindrical resistive film, achieving a reflectivity of -15 dB across the 2-18 GHz frequency range. Experimental testing in an anechoic chamber demonstrated that the fabricated sample's performance closely matched the full-wave simulation results, thereby validating the effectiveness of the design.