LS (Lossy Foam) 

ML (Multilayer Foam) 

RT (Reticulated Foam)


Dielectric Foam

Lightweight and flexible, broadband foam absorbers are highly effective at absorbing RF and microwave energy. Single-layer LS foam can be tailored for low or high insertion loss. Multilayer foam absorbers offer at least -17dB reflection loss from 500MHz to 40GHz, depending upon thickness. Reticulated foam can be frequency specific. Dielectric foam absorbers are available as sheets or cut pieces, with optional PSA for easy attachment.


Applications include:

  • Antenna applications

  • EMC test chambers

  • Telecom equipment

  • Microwave transceivers

  • Airport systems

Foam & Honeycomb Absorbers

Multilayer Foam Absorber

This range of absorbers is designed for suppression of interference and side-lobes, isolation of adjacent antennae, camouflaging, lining walls, surfaces and chambers to reduce reflectivity.

HEM D-Foam PP2

Dielectric Honeycomb Absorber

Salisbury Screen & Jaumann Speciality Foam Absorber

Frequently Asked Questions

At what frequencies do absorbers function?

We supply absorbers from ARC Technologies, which attenuate as low as 100MHz and up to 100GHz, depending on the product.

What type of absorber would you recommend for broadband reflection loss?

 ARC Technologies ML series of multi-layer foam absorbers are the preferred choice for broadband reflection loss. Depending on the part selected, at least -17dB of loss can be expected from 650MHz to 40GHz. Thicknesses range from 6.4mm to 114.3mm.

Does an absorber need to be attached to metal in order to function properly?

In most cases, yes - attaching the absorber to an electrically reflective metal surface provides a low impedance plane to which the signal will travel as it passes through the absorber. The metal surface need not be grounded. If there is not a metal surface available, HITEK can install a thin foil or metallised film at the back of the absorber.

What absorber would you recommend to use for controlling side lobes in antennas?

ARC Technologies’ RT series reticulated foam absorbers are a good choice. The large cell structure promotes air circulation to prevent moisture entrapment and they can be made frequency specific. 

What’s the difference between reflection loss and insertion loss?

Reflection loss (expressed in decibels, dB) is the ratio of reflected power to incident power. In simple terms, it means the reduction of a signal after it has attenuated through an absorber and reflected back via a reflective surface behind the absorber. Insertion loss, also known as transmission loss, is the reduction in power of a signal as measured after it has passed through an absorber having no reflective surface behind it.

What is a resonant absorber?

A resonant absorber is designed to attenuate an electrical signal in far field, only at certain predetermined frequencies. While broadband absorbers such as ARC Technologies’ ML series may be said to be resonant, they exhibit this characteristic over a wide frequency range. More commonly, the term resonant refers to narrow band magnetic absorbers such as ARC Technologies’ DD, UD, CD or ND series. The resonant absorber will be designed to attenuate just a certain target frequency while leaving other frequencies relatively untouched or more moderately attenuated.

Can absorbers be used outdoors?

Microwave and RF absorbers must be protected from the environment. We are able to wrap foam absorbers with CoverLite; a tough, flexible weather resistant covering for applications where the absorber is directly exposed to the elements.