PYRAMIDAL RF MICROWAVE ABSORBERS (FU-SE)

FU-SE absorber product line is a complete range of high performance pyramidal microwave absorbers.

Available in wide range of thickness and absorbencies. Variety of thickness gives the chamber designer an opportunity to choose grades appropriate for specific frequencies and incidence angles.

Constructed using low density, flexible foam, impregnated with a carbon black ferrite formulation to achieve the desired electrical performance

The pyramidal structure gives it the geometrical matching and the carbon dispersed gives the attenuation required at near normal incidences

Provide engineers with the building blocks needed in the design and construction of RF absorbing surface used in anechoic chambers, antenna assemblies and microwave measuring facilities.

Absorber Type Thickness in inches Reflectivity(dB) for near normal incidence relative to metal surface of same size at different frequency
80 MHz 250 MHz 500 MHz 1 GHz 3 GHz 10 GHz 18 GHz to 40 GHz
FU-SE- 70/45/36 70/45/36 TO BE DESIGNED FOR THE GIVEN FERRITE TO MAKE HYBRID ABSORBERS AT LOW FREQUNCIES
FU-SE-24 24 -6 -20 -35 -40 -50 -50 -50
FU-SE-18 18 -30 -40 -45 -50 -50
FU-SE-12 12 -35 -40 -50 -50
FU-SE-8 8 -30 -40 -50 -50
FU-SE-4 4 -25 -40 -50
FU-P-SE-24 24 -30 -40 -40 -45 -40
FU-P-SE-12 12 -35 -40 -45 -40

FEATURES:

  • Absorption over a wide frequency range.
  • Long product life.
  • High performance, up to -50 dB attenuation.
  • These absorbers are supplied with a fire retardant finish.
  • RoHS Compliant

MATERIAL PROPERTIES:

  • Color: As Desired, generally available in blue color.
  • Dimensions: 60 cm X 60 cm.
  • Chemical Composition: Carbon ferrite impregnated polyurethane foam
  • Maximum service temperature: 90 degree Centigrade
  • Power handling capacity: 0.5 Watt/in2 (Under forced air cooling) And 0.15 Watt/in2 (In normal air conditioned room)
  • Fire Retardency: Passes NRL-8093, test 1, 2 & 3 With Zero Halogen Means.
  • Our foam absorbers are fire retardant with zero halogen means thereby avoid formation of toxic gases like HCl/HBr and poisonous gases like phosgene.

AREAS OF APPLICATION:

  • Broadband absorbers suitable for in-door measurements.
  • Used in making microwave anechoic chambers for performing measurements like RCS, Antenna Measurements etc.
  • Used in making Moving screens for hiding the areas of maximum reflections.
  • Used for obtaining Quiet Zones in very wide frequency range.

WEDGE MICROWAVE ABSORBERS(FW-SE)

Reflection Loss (dB) of wedge type (FW-SE) at normal incidence is 3 dB to 5 dB down in comparison of our pyramidal microwave absorber (FU-SE).

FW-SE absorber is a complete range of high performance wedge microwave absorbers having approximated same properties at grazing incidences as our FU-SE Series-Pyramidal Microwave Absorbers at near normal incidences.

Constructed using low density, flexible foam, impregnated with a carbon black, ferrite formulation to achieve the desired electrical performance.

At higher angle of incidences backscatter is significantly reduced.

Available in wide range of thickness and absorbencies.

Variety of thickness gives the chamber designer the opportunity to choose grades appropriate for specific frequencies and incidence angles.

FEATURES:

  • Absorption over a wide frequency range.
  • Long product life.
  • High performance, up to - 45 dB reflection loss at grazing incidences.
  • These absorbers are supplied with a fire retardant finish.
  • RoHS Compliant.

MATERIAL PROPERTIES:

  • Color: As Desired, generally available in blue color.
  • Dimensions: 60 cm X 60 cm.
  • Chemical Composition: Carbon ferrite impregnated polyurethane foam
  • Maximum service temperature: 90 degree Centigrade
  • Power handling capacity: 0.5 Watt/in2
  • Fire Retardency: Passes NRL-8093, test 1, 2 & 3 With Zero Halogen Means.
  • Our foam absorbers are fire retardant with zero halogen means thereby avoid formation of toxic gases like HCl/HBr and poisonous gases like phosgene.

AREAS OF APPLICATION:

  • Broadband absorbers suitable for in-door measurements.
  • Used in making microwave anechoic chambers for performing measurements like RCS, Antenna Measurements etc.
  • Used in making Moving screens for hiding the areas of maximum reflections.
  • Used for obtaining Quiet Zones in very wide frequency range.

WALK - ON MICROWAVE ABSORBERS (FU-FL)

Walk on absorbers are manufactured from our standard blocks of PU foam based pyramidal / wedge absorbers with a profiled section filled with a low loss, polystyrene foam thus making it a flat faced absorber.

Absorber Type Thickness in inches Reflectivity(dB) for near normal incidence relative to metal surface of same size at different frequency
80 MHz 250 MHz 500 MHz 1 GHz 3 GHz 10 GHz 18 GHz to 40 GHz
FU-FL-SE-36 40 -6 -25 -35 -35 -35 -35 -30
FU-FL-SE-24 28 -6 -20 -30 -30 -30 -30 -30
FU-FL-SE-12 18 -25 -30 -35 -30

FEATURES:

  • Absorption over a wide frequency range.
  • Long product life.
  • High performance.
  • These absorbers are supplied with a fire retardant finish.
  • RoHS Compliant.

MATERIAL PROPERTIES:

  • Color: As Desired, generally available in blue color.
  • Dimensions: 60 cm X 60 cm.
  • Chemical Composition: Carbon ferrite impregnated polyurethane foam
  • Maximum service temperature: 90 degree Centigrade
  • Power handling capacity: 0.5 Watt/in2
  • Fire Retardency: Passes NRL-8093, test 1, 2 & 3 With Zero Halogen Means.
  • Our foam absorbers are fire retardant with zero halogen means thereby avoid formation of toxic gases like HCl/HBr and poisonous gases like phosgene.

AREAS OF APPLICATION:

  • Intended for use in areas on the floor.
  • Structure capable of supporting the weight of a man.
  • Required when access to test areas is required.

CONVOLUTED MICROWAVE ABSORBERS - (FU-CV)

A PU Foam based broadband microwave absorber Almost equally effective at wider angles of incidence as well.Light weight, flexible and easy to cut.

Polyurethane foam material (flexible) block having a front surface cut to a convoluted (Egg Carton) shape, dipped in absorbing slurry providing desired electrical grading.

Because of the rounded convolutions, and lacking sharp corners and points, FC absorber is the preferred absorber for millimeter wave frequencies, and for very wide incidence angles Standard size is 600 mm X 600 mm.Custom tailored sizes can also be supplied.

Standard thickness: 100 mm. Available in different thicknesses.

Absorber Type Thickness in inches Reflectivity(dB) for near normal incidence relative to metal surface of same size at different frequency
8 GHz 10 GHz 30 GHz 50 GHz 80 GHz
FC-4 4 -25 -30 -30 -35 -30

FEATURES:

  • Absorption over a wide frequency range.
  • Long product life.
  • Our foam absorbers are fire retardant with zero halogen means thereby avoid formation of toxic gases like HCl/HBr and poisonous gases like phosgene.
  • RoHS Compliant

MATERIAL PROPERTIES:

  • Color: As Desired, generally available in blue color.
  • Typical Weight of 60 cm X 60 cm sheet: 1.5 kg.
  • Chemical Composition: Carbon ferrite impregnated polyurethane foam.
  • Maximum service temperature: 90 degree Centigrade.
  • Fire Retardency: Passes NRL-8093, test 1, 2 & 3 With Zero Halogen Means.

AREAS OF APPLICATION:

  • Best Suited at millimeter wave frequencies.
  • Most suitable for areas where non-specular/near field scattering is to be minimized.
  • Various camouflaging and interference suppression applications.
  • Used for Low performance Anechoic Chambers in non critical areas.
  • Preferable for Millimeter Wave Anechoic Chambers.
  • Lining the tapered walls of Tapered Anechoic Chambers.
  • Suitable for Low cost Anechoic chambers at frequencies above 8 GHz.

MULTI-LAYER FLAT MICROWAVE ABSORBERS (FU-ML)

Lightweight, flexible, broadband, Multilayer PU foam based microwave absorber. Fabricated using six layers of carbon impregnated foam. FU-ML is an electrically graded flat PU foam based microwave absorber. Carbon loaded laminate polyurethane sheets. Can be readily cut on a band saw, with scissors, or a sharp knife. Available in various thicknesses from 18 mm to 120 mm and beyond. FU-ML is not waterproof and will not operate correctly when wet, since there is not washout, FU-ML will function as expected after being allowed to dry.

Absorber Type Thickness in mm Reflectivity(dB) for near normal incidence relative to metal surface of same size at different frequency
800 MHz 900 GHz 2 GHz 40 GHz & Higher Frequencies
FU-ML-120 120 -15 -15 -17 -17

FEATURES:

  • Our foam absorbers are fire retardant with zero halogen means thereby avoid formation of toxic gases like HCl/HBr and poisonous gases like phosgene.
  • RoHS Compliant.

MATERIAL PROPERTIES:

  • Color: As Desired, generally available in blue color.
  • Typical Weight of 60 cm X 60 cm X 12 cm sheet: 2.5 kg.
  • Chemical Composition: Carbon ferrite impregnated polyurethane foam.
  • Maximum service temperature: 90 degree Centigrade.
  • Fire Retardency: Passes NRL-8093, test 1, 2 & 3 With Zero Halogen Means.

AREAS OF APPLICATION:

  • FU-ML has been used in reducing cross talk 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.
  • Shadowing of posts and supports in anechoic chambers, and as absorbing blankets for testing radar systems without harm to personnel.
  • FU-ML is also effective in reducing surface current waves on metal shapes.

PU FOAM BASED ANTENNA SHROUD MICROWAVE ABSORBERS

Semi Open PU Foam based broadband type embedded pyramidal microwave absorbers. Specially formulated coatings for better ageing characteristics. Light weight, flexible and easy to cut. Polyurethane foam sheet dipped in absorbing slurry providing desired electrical grading. Standard size is 600 mm X 600 mm. Custom tailored sizes can also be supplied. Thicknesses are 45mm, 35mm, 30mm, 25mm, 15mm, 12.5mm and 10 mm (FAS-45, FAS-35, FAS-30, FAS-25, FAS-15, FAS-12.5 and FAS-10). Larger thickness can be produced to suit low frequency applications. Colored surface should face the incident radiation. The back surface (black) should be close to the metallic surface to achieve best performance. Provides better wider angle performance than multilayer flat absorber.

Absorber Type Reflectivity(dB) for near normal incidence relative to metal surface of same size at different frequency
4.5 to 5.5 GHz 7.0 to 8.0 GHz 8.0 to 10.0 GHz 10.0 to 12.0 GHz 12.0 to 15.0 GHz 15.0 to 40.0 GHz
FAS-45 -15 -16 -16 -20 -20 -20
FAS-35 - -16 -16 -20 -20 -20
FAS-30 - -15 -15 -20 -20 -20
FAS-25 - -15 -15 -20 -20 -20
FAS-15 - - - -15 -15 -15
FAS-12.2 - - - -13 -15 -15
FAS-10 - - - - -13 -15

FEATURES:

  • Our foam absorbers are fire retardant with zero halogen means thereby avoid formation of toxic gases like HCl /HBr and poisonous gases like phosgene.
  • RoHS Compliant.

MATERIAL PROPERTIES:

  • Color: As Desired, generally available in blue color.
  • Typical Weight of 60 cm X 60 cm X 12 cm sheet: 2.5 kg.
  • Chemical Composition: Carbon ferrite impregnated polyurethane foam.
  • Maximum service temperature: 90 degree Centigrade.
  • Fire Retardency: Passes NRL-8093, test 1, 2 & 3 With Zero Halogen Means.

AREAS OF APPLICATION:

  • FAS has been used in reducing cross talk 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.
  • Shadowing of posts and supports in anechoic chambers, and as absorbing blankets for testing radar systems without harm to personnel.
  • FAS is also effective in reducing surface current waves on metal shapes.

PYRAMIDAL HYBRID MICROWAVE ABSORBER

  • TOTAL PYRAMID:
  • Our FHY type absorber are pyramidal shaped flexible polyurethane foam based carbon / ferrite powder loaded hybrid absorber which are made for use in EMC test chambers. These FHY absorbers are to be combined with ferrite tiles to perform at lower frequencies and a low density matching dielectric layer to make hybrid absorber suitable at higher frequencies as well. FHY Absorber is available in three thicknesses viz 30.0cm, 45cm and 60cm thick and termed as FHY-12, FHY-18 and FHY-24 respectively.

  • TRUNCATED:
  • FHY Absorbers are available in truncated version where tips of the pyramid are removed for saving space in chambers and tip breakage thus making a more rugged product. This is done at the expense of their performance at higher frequencies. Truncated absorbers are available in 30 cm and 45 cm thickness and are termed as FHY-12-T and FHY-18-T, respectively.

    A typical performance of these hybrid microwave absorbers (FHY + Ferrite + Dielectric) at near normal incidence shall be as under at different frequencies.

    Absorber Type Reflectivity(dB) for near normal incidence relative to metal surface of same size at different frequency
    30 MHz 50 MHz 80 MHz 250 MHz 1 GHz 10 GHz 20 GHz 30 GHz 40 GHz
    FHY-12 -13 -15 -18 -15 -16 -18 -30 -40 -40
    FHY-18 -14 -15 -18 -15 -16 -20 -35 -40 -40
    FHY-24 -14 -15 -18 -15 -20 -25 -40 -40 -40
    FHY-12-T -14 -15 -18 -15 -16 -15 -15 NR NR
    FHY-18-T -14 -15 -18 -15 -16 -15 -15 NR NR
    NR-Not Recommended.

    FEATURES:

    • Our FHY absorbers are optimized for a particular ferrite tiles /dielectric combination.
    • Our foam absorbers are fire retardant with zero halogen means thereby avoid formation of toxic gases like HCl /HBr and poisonous gases like phosgene.
    • RoHS Compliant.

    MATERIAL PROPERTIES:

    • Colour: As Desired, generally available in blue color.
    • Dimensions: 60 cm X 60 cm.
    • Chemical Composition: Carbon ferrite impregnated polyurethane foam.
    • Maximum service temperature: 90 degree Centigrade.
    • Power handling capacity: 0.5 Watt/in2.
    • Fire Retardency: Passes NRL-8093, test 1, 2 & 3 With Zero Halogen Means

    AREAS OF APPLICATION:

  • EMI /EMC test ranges.
  • PLASTIC COATED POLYURETHANE FOAM BASED RF MICROWAVE ABSORBERS FOR OUT-DOOR / CLEAN ROOM APPLICATIONS

    FU-SE-X-PC is a plastic coated weatherproof absorber highly suitable for Open Test Sites. Performance of this Class of Absorber is not affected due to water on to the surface of pyramid. It is resistant to Outdoor weather condition like sunlight, Rain, Dust etc. Life expectancy of this absorber is greater than 5 Years and it can be enhanced when not in use, when stored under control Environmental condition.

    Absorber Type Thickness in inches Reflectivity(dB) for near normal incidence relative to metal surface of same size at different frequency
    250 MHz 500 MHz 1 GHz 3 GHz & Higher Frequencies
    FU-SE-24-PC 24 -20 -35 -40 -45
    FU-SE-18-PC 18 -30 -35 -45
    FU-SE-12-PC 12 -30 -40

    FEATURES:

    • Excellent RF performance with weather resistance.
    • Absorption over a wide frequency range.
    • Long product life.
    • High performance, up to -45 dB attenuation.
    • These absorbers are supplied with a fire retardant finish.
    • Useful for CLEAN Room Conditions.

    MATERIAL PROPERTIES:

    • Color: As Desired, generally available in RED color.
    • Dimensions: 60 cm X 60 cm
    • Chemical Composition: Fire Retardant Plastic Coated Carbon ferrite impregnated polyurethane foam
    • Maximum service temperature: 90 degree Centigrade
    • Power handling capacity: 0.5 Watt/in2
    • Fire Retardency: Passes NRL-8093, test 1, 2 & 3 With Zero Halogen Means.
    • Our foam absorbers are fire retardant with zero halogen means thereby avoid formation of toxic gases like HCl / HBr and poisonous gases like phosgene.

    AREAS OF APPLICATION:

    • Broadband absorbers suitable for Outdoor measurements.
    • Used in making Moving screens for hiding the areas of maximum reflections.
    • Used for obtaining Quiet Zones in very wide frequency range.


    ADDRESS

    • Sahajanand Laser Technology Ltd E-30, GIDC, Sector 26, Electronics Estate, Gandhinagar, Gujarat - 382 028, INDIA.
    • Email: microwave@sahajanandlaser.com
      kanhiyalal@sahajanandlaser.com
    • Website: www.sltmicrowave.com
    • Contact Person: Dr. Kanhiya Lal
      Mobile No: +91 - 9810596888