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Hybrid & Microwave absorbers


Polystyrene absorbers for EMC and microwave test facilities

All our absorbers are high performance polystyrene microwave absorbers suited for all kinds of RF anechoic chambers. The product range consist of both hybrid (EMC) and microwave (broadband) absorbers.


Green and sustainable

These closed cell polystyrene absorbers don't contain poisonous fire retardant chemicals. Hence the absorbers are sustainable, 100% environmental friendly and fully compliant with REACH and ROHS.


Benefits of the polystyrene microwave absorbers

The benefits of the microwave absorbers are:
•   Unique and enhanced product design:
•    Alternating taper design (vertical – horizontal) resulting in improved reflectivity performance.
•    Light weight
•    Removable tapers
•   Hybrid absorbers are suitable for clean room class 4 as per ISO14644-1 / class 10 as per US Fed. Standard 209E
  •  Microwave absorbers are suitable for clean room class 2 as per ISO14644-1 / class 1 as per US Fed. Standard           209E
•   Uniform carbon cell loading results in a more stable performance.
•   Rigidity and superior tensile strength (no drooping tips)
•   Superior product life time (>40 years)
•   Resilience to humidity.

 

Hybrid absorbers for EMC test facilities

The hybrid polystyrene absorber range is designed for typical chamber solutions such as 3, 5 and 10m semi or full anechoic chambers, compact rooms and automotive test chambers. The hybrid absorber is a high performance, ultra wide band, carbon loaded polystyrene absorber with an operating frequency from 20MHz to 40GHz. The HT hybrid absorbers are tuned for perfect performance in combination with ferrite tiles in EMC test facilities.


The HT series consist of three different models:

•    HT25 (250mm / 10”)
•    HT45 (450mm / 18”)
•    HT65 (650mm / 26”)

All absorbers consist of a single base plate and separate tapers. The absorber base dimensions are 1200*600mm.
Upon customer request the hybrid absorbers can be equipped with white end caps.




Specifications of the hybrid absorber range:

Material
Dimensions
Weight
Color
Humidity resistance
Product life time
Power Handling
Frequency range
Fire retardancy
Clean room spec:
White end cap
Reach compliant
ROHS compliant
Closed-cell polystyrene
1200*600*450mm (height)*
5,7 Kg / m2*
Dark Grey
No deterioration from moisture
 >40 years
434 V/m
20MHz – 40GHz
ISO 11925-2 class E / DIN 4102 class B2
ISO14644-1 class 4 / US Fed. Standard 209E class 10
Upon request, 2 square caps per absober
Yes
Yes

*: HT45.



*The typical performance is based on the cascade solution in combination with the FT106.


Field Uniformity (FU) test floor set up

The HT45 absorber is also suited for field uniformity floor set up configurations according to the IEC/EN-61000-4-3 standard in semi anechoic chambers used for EMC testing. To protect the absorber tips whilst stacking the HT45 can be equipped with two grey end caps model ECT45-G.


Wideband Ferrite Floor Absorber model 1701-000.

The wideband ferrite floor absorber model 1701-000 is designed to facilitate the use of all semi anechoic chambers for full compliance immunity testing. In combination with the hybrid absorber model HT45 the ferrite floor absorber is perfectly suited for a floor setup for immunity testing according to IEC/EN-61000-4-3. Dimensions: 602*602*20mm / weight: 17kg.

  


Ferrite Tile model 1701-200

The hybrid ferrite tile model 1701-200 is a sintered ferrite tile and delivers excellent electromagnetic absorption performance from 20MHz ~1GHz. The ferrite tile can be directly glued to the shielding enclosure or screwed to an inner structure which enables easy installation. Ferrite absorbers are also suited for hybrid (cascade) solutions in combination with the EMC hybrid polystyrene absorbers (HT series) in EMC test chambers.

 

Microwave absorbers for antenna test chamber applications

The MT microwave absorber range consist of high performance, broad band, carbon loaded polystyrene absorbers with an operating frequency from 70MHz to 40GHz. Due to the excellent performance at microwave frequencies the MT series is designed for Antenna Pattern Measurement (APM), (compact) Antenna Test Range (ATR) Radar Cross Section (RCS), and free space testing anechoic chamber applications.


NEW MT45 Javelin Tip absorber

More information about the MT45-JT is found here: Javelin Tip Absorbers


The MT series consist of four different models:

•    MT25 (250mm / 10”)
•    MT45-JT (450mm / 18”)
•    MT50 (500mm / 20”)
•    MT65 (650mm / 26”)
•    MT105 (1050mm / 41”)

All absorbers consist of a single base plate and separate tapers. The absorber base dimensions are 1200*600mm. 


Specifications of the microwave absorbers:

Material
Dimensions
Weight
Color
Humidity resistance
Product life time
Power Handling
Frequency range
Max operating temp.
Fire retardancy
Clean room class
Reach compliant
ROHS compliant
Closed-cell polystyrene
1200*600*450mm (height)*
7,36 Kg / m2*
Dark Grey
No deterioration from moisture
>40 years
1500 W/m2
70MHz – 40GHz
70 oC.
ISO 11925-2 class E / DIN 4102 class B2
ISO14644-1 class 2 / US Fed. Standard 209E class 1
Yes
Yes

 *: MT45-JT.


 

sVSWR floor set up

The MT25 absorber is also suited for sVSWR floor set up configurations according for CISPR 16-1-4 testing in semi anechoic chambers used for EMC testing. The MT25 consist of a single base plate and 128 tapers. The absorber dimensions are 1200*600*250mm (h). To protect the absorber tips whilst stacking the MT25 can be equipped with two grey end caps model ECT-25-G.


 

Walkway absorber solutions

The walkway solution is designed to provide safe and easy access for the test engineers to the antenna and EUT in full anechoic chambers. Due to the use of connectable fiberglass reinforced epoxy grid panels, they combine extreme strength with minimal RF scattering. This walkway is available as a cascade with floor absorber (WWA) and without (WW).

It is recommended to use the walkway in the non-critical area of the chamber and at a reduced height compared to the applied floor absorber. For example if the floor absorber is MT-45, the WWA-MT25 shall be used. The reflectivity of this walkway solution corresponds to that of the performance of the absorber under the walkway for frequencies up to 3GHz. Above 3 GHz the reflectivity (backscatter) performance is limited to -40dB. Despite the specular reflection (scatter) is in the order of -20dB, the angle of incidence equals the angle of reflection and therefore the unwanted waves will damped by the absorber lining of the chamber. Due to the reduced height of the walkway and the above mentioned RF characteristics, the influence of the walkway on the measurements in the chamber is neglect able as long as the walkway is used in the non-criical area of the chamber.

The walkway solution model WWA is available in the following models:
 
WWA-HT25 Walkway solution using HT25 absorber (hybrid)
WWA-MT25 Walkway solution using MT25 absorber (microwave)
WWA-HT45 Walkway solution using HT45 absorber (hybrid)
WWA-MT45-JT Walkway solution using MT45-JT absorber (microwave)


Specifications of the walkway absorber solutions:

 
Material Reinforced glass fibre epoxy grid
Dimensions grid 1186x577x25mm
Product life >25 years
Color RAL 7035 / grey
Height of WWA-HT25/MT25 295mm (tot. height)
Height of WWA-HT45/MT45-JT 495mm (tot. height)
Recommended maximum distributed load 6kN
Breaking load* 27kN                                                                                

*Breaking load is defined as a stress or tension just steady enough to cause a break or rupture