FLEXIBLE FOAM SHEET BROADBAND MICROWAVE ABSORBER. Application : Physical Properties :

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1 EB-010 FLEXIBLE FOAM SHEET BROADBAND MICROWAVE ABSORBER Description : Eccosorb AN is a lightweight, flexible, foam sheet broadband microwave absorber. It is available in 6 standard grades, depending upon the lowest desired frequency of operation in the frequency range from 600 MHz - 40 GHz. Eccosorb AN is designed to reflect less than -17 db of normal incident energy above specified frequencies and relative to a metal plate. Application : Eccosorb AN is being used for reducing crosstalk between adjacent antennas, shrouding antennas to improve the antenna patterns and undesired back lobes, as well as selective shadowing of parts of a target for RCS measurements. It can also be used for shadowing posts and supports in anechoic chambers, and as absorbing blanket for testing radar systems without harm to personnel. For isolation of components or antennas by means of insertion loss, it can be used without a metal backing. Physical Properties : AN Front surface colour White Back surface colour Black Max. Service Temperature( C ) 90 Power Handling ( W/cm² ) 0.15 Fire Retardancy UL94-HBF Nominal dimensions and weight of Eccosorb AN : Grade Total Thickness (cm) Nominal weight (kg/pc) AN AN AN AN AN AN

2 ECCOSORB AN FLEXIBLE FOAM SHEET BROADBAND MICROWAVE ABSORBER Electromagnetic properties : GRADE AN-72 AN-73 AN-74 AN-75 AN-77 AN-79 Reflectivity Range (-17 db) 20 GHz >7.5 GHz >3.5 GHz >2.4 GHz >1.2 GHz >600 MHz 0 Typical reflectivity at various angles of incidence Eccosorb AN-73 Perpendicular polarisation Reflectivity (-db) Frequency (GHz) Typical reflectivity at various angles of incidence Eccosorb AN-73 Parallel polarisation Reflectivity (-db) Frequency (GHz)

3 EB-010 ECCOSORB AN FLEXIBLE FOAM SHEET BROADBAND MICROWAVE ABSORBER Availability : Eccosorb AN is available in six standard thicknesses depending upon the lowest desired frequency of operation. Standard sheets are 610 mm x 610 mm. Eccosorb AN is available upon special order in other sizes and customer specified configurations, incorporating mitre cuts or attachment to metal parts. It can be manufactured, on special order, on a mandrel, to take a contoured shape. Related products with improved outdoor properties : Eccosorb AN is not waterproof and will not operate correctly when wet. Therefore the material is not recommended for outdoor use. However since there is no washout, Eccosorb AN will still function properly when dried. For high humidity to moderately wet environments, sealed versions of Eccosorb AN are available. They are essentially the same material as Eccosorb AN but the absorber is sealed to provide improved outdoor properties. The available types are : Eccosorb AN Weatherproof : sealed with neoprene coated nylon fabric, olive green or grey. Eccosorb AN-xx-WPC : sealed with a polyurethane coating, different colours available on requesthitek Electroni Eccosorb AN-xx-WPVC : sealed with a PVC plastic, different colours are available on request and can be provided with eye-lets for fixing. Reflectivity performance is similar to the standard Eccosorb AN product. HEM830 Waterproof puncture resistant vinyl covering. Available in Blue, Red, Black and White Instructions for use : To obtain low reflectivity, the absorbers must be mounted on a metal surface. If a metal surface is not available, Eccosorb AN can be supplied metal backed with aluminium foil (ML). For correct operation Eccosorb AN must have the white (front) face towards the signal to be attenuated*. Layering of multiple pieces or slicing off part of the thickness will degrade the overall performance. Eccosorb AN can be securely bonded to itself or to other materials such as metal, wood, and common plastic composites. The recommended adhesive is Eccostock Adhesive It can be readily cut on a band saw, with scissors, or a sharp knife. Safety Considerations : It is recommended to consult the EMERSON & CUMING MICROWAVE PRODUCTS product literature, including material safety data sheets, prior to use EMERSON & CUMING MICROWAVE PRODUCTS products. These may be obtained from your local sales office. WARRANTY : Values shown are based on testing of laboratory test specimens and represent data that falls within the normal range of properties of the material. These values are not intended for use in establishing maximum, minimum or ranges of values for specification purposes. Any determination of the suitability of the material or any use contemplated by the user and the manner of such use is the sole responsibility of the user who must assure that the material as subsequently processed meets the needs of this particular product or use. We hope the information given here will be helpful. It is based on data and knowledge considered to be true and accurate and is offered for the user s consideration, investigation and verification but we do not warrant the results to be obtained. Please read all statements, recommendations or suggestions in conjunction with our conditions of sale INCLUDING THOSE LIMITING WARRANTIES AND REMEDIES which apply to all goods supplied by us. We assume no responsibility for the use of these statements, recommendations or suggestions nor do we intend them as a recommendation for any use which would infringe any patent or copyright. 2011/01 - V02/1 Emerson & Cuming Microwave Products N.V., Nijverheidsstraat 7A, B-2260 Westerlo, Belgium. ECCOSORB, ECCOSTOCK, ECCOSHIELD, ECCOLENS, ECCOPAD are registered trademarks of EMERSON & CUMING MICROWAVE PRODUCTS N.V

4 Eccosorb AN PRODUCT Type Chemical Composition Manufacturer Flexible-foam microwave absorber. Loaded Polyurethane. EXPERIENCE and AVAILABILITY Development Status Cost Range Lot Reproducibility Commercial Product Medium Variable Space Experience Fair GENERAL PROPERTIES (Physical, Mechanical, Thermal, Electrical, Optical) Nature Typical Value Remarks Frequency Range 455 MHz Manufacturer s Data Mass per Unit Area 0,05 g cm -- 2 to 1 g cm -- 2 Manufacturer s Data PROPERTIES RELEVANT TO SPACE USE Nature Typical Value Type of Test Temperature Range 150 ºC max. Manufacturer s Data Outgassing TML = 1,30 %, RML =0,4 %, CVCM = 0,04 % ECSS--Q (after cleaning*) Flammability No ignition NASA-STD-6001 SPECIAL RECOMMENDATIONS * Cleaning process according to ESA PSS compulsory. Unit 44, Captain Cook Drive Caringbah 2229 NSW Australia P:

5 ECCOSORB AN HITEK Electronic Materials Ltd. Distribution of Innovation. HITEK Electronic Materials Ltd. Distribution of Innovation.

6 Ɛ" 0 ECCOSORB AN72 PERMITTIVITY_Ɛ" AN72 FRONT AN72 BACK -10 Frequency (GHz)

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8 Basic principle of a graded absorber If incoming wave "sees" a medium with very different electrical properties, the medium will act as a reflector due to the impedance discontinuity. The higher the dielectric constant, the more is reflected. Hence a very lossy medium will act as a reflector Need to match the impedance at the front face of absorber closely to air to minimize reflection Absorption bandwidth can be increased by cascading multiple layers, similar to bandpass filter design. 17 to 20 db absorption bandwidths of N:1 (n= number of layers) achievable. Wide absorption bandwidth can also be achieved by gradual impedance taper. Reflections occur at impedance discontinuities with the level of reflection proportional to the amount of impedance discontinuity By tapering the impedance from close to free space at the front of the absorber to more lossy at the base, reflections are minimized. 1. Material layer taper (Eccosorb AN)-Material consists of discrete layers graded from low loss at front to high loss at back 2. Material property taper (Eccosorb HR) - Flat sheet of material graded from lower loss at the front face to higher loss at the rear face. Unit 44, Captain Cook Drive Caringbah 2229 NSW Australia P: