ESorb Broadband Foam Absorber

ESorb broadband absorbers are typically used in open-space applications, where the absorber material provides high attenuation and significantly reduces the application’s reflectivity. ESorb absorber materials are designed for a broad frequency range from UHF to EHF. Broadband absorbers are manufactured from various base materials, such as flexible and rigid polyurethane foam.

Typical broadband applications include reducing the reflectivity of metal structures and masts, minimizing interference between different antenna systems, modifying the RCS, and enhancing stealth capabilities. Custom solutions tailored to specific customer requirements are also available.

The most common broadband absorbers are described below.

ESorb-MLA

ESorb-MLA absorbers are flat, lightweight, carbon-filled foam absorbers. The flat absorber is a multilayer structure consisting of individually tuned absorber layers, each with a specific dielectric gradient to achieve the best possible match to the impedance of air. The absorber panels have a controlled dielectric charge and are impregnated with a binder and flame-retardant additives. This absorber material is available in six different thicknesses, with each thickness corresponding to a specific operating frequency. The typical reflection coefficient of the absorber is -17 dB at normal incident power.

ESorb-MLA is a typical broadband absorber that can be used both in open spaces and in cavities. For special applications where the absorber is used in a harsh environment, we can supply the absorber material with a protective covering such as vinyl, fabric, or a coating.

ESorb-OFA

ESorb-OFA is a series of lightweight, open-cell (mesh-like) microwave foam absorbers. The single-layer, mesh-like polyurethane foam is coated with a dielectric carbon solution that has flame-retardant properties. Due to its open-cell structure and a specialized production process, the absorber material exhibits a dielectric conductivity gradient, enabling it to achieve excellent RF performance. Various thicknesses are manufactured to meet customers’ mechanical and RF requirements. The standard thicknesses are 5, 10, 15, and 25 mm. The typical operating frequency is above 3 GHz; the thickest material is used in the low-frequency range.

If reflective performance is required, the material can be supplied with an integrated metal backing. Similar to our other polyurethane-based absorbers, ESorb-OFA can also be supplied with a protective fabric. A vinyl fabric is typically used for this purpose.

ESorb-CFA

The ESorb-CFA series includes various high-performance, cone-shaped microwave absorbers. The absorber consists of a lightweight polyurethane foam impregnated with a dielectric carbon and a flame-retardant solution. ESorb-CFA has the characteristic curved shape on the front side. The material provides an ideal conical impedance profile, which gives the absorber excellent RF performance at higher frequencies. Due to its specific shape, the absorber material maintains its high performance level regardless of the angle of the incident energy or the signal polarization.

They are manufactured in three different heights: 3, 4, and 6 inches. The typical operating frequency is above 1 GHz.

ESorb-SLA

ESorb-SLA absorbers are flat, flexible microwave absorbers made from polyurethane foam impregnated with a dielectric carbon charge. Various dielectric grades and thicknesses are available, with the material typically characterized by its attenuation coefficient at a specific frequency. By adjusting the thickness and loss power, the attenuation properties can be tuned to optimize the required attenuation. Lossy foam panel absorbers are a cost-effective solution for absorbing unwanted RF signals above 1 GHz. The absorber consists of a carbon-enriched foam, which can be additionally coated if necessary to prevent the release of dust.

In addition, we can apply a protective layer—such as vinyl, fabric, or a coating—to the absorber material upon request. The absorber material can also be used to insulate antennas by taking advantage of its damping properties. ESorb-SLA is often supplied with a self-adhesive backing. The material can be easily cut with a knife.

You can find an overview of our broadband absorbers, including data sheets, here.

We would be happy to help you choose the right gasket for your needs. Contact our team here or request a free material sample.