ORBIT FR Millimeter Wave Absorbers - AEC-MM Series - Manual (Page 2)

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1/ Description
Custom designs for a low-grazing application has lead to
the development and manufacture of AEMI’s Millimeter
Wave tapered absorbers. These materials were develo-
ped for chamber applications where main beam energy
of the source antenna was focused on the sidewalls of
the chamber, due to its long overall length. These mate-
rials were effectively used in the overall chamber design
to provide the required test environment at 45 GHz.
• Type AEC-4-MM is our standard material optimized for
millimeter wave operation. By proper selection of the
carbon loading, refl ectivity on the order of 45 to 50 dB
has been attained consistently at normal incidence
over the 18 to 40 GHz frequency range.
• Type AEC-4/1-MM-HP is a high performance mate-
rial using convoluted front face foam which has a very
regular cell structure and is essentially window free.
By properly selecting the carbon loading, refl ectivity
on the order of 50 to 55 dB has been consistently
attained at normal incidence at 95 GHz. The mate-
rial has a second layer that is necessary to provide
the low frequency performance of -40 dB at 28 GHz.
Good performance down to 10 GHz is achievable by
properly adjusting the backing material.
• Type AEC-4/5-8T-MM is a high performance material
for use in long, narrow chambers where the energy
illuminating the side walls is arriving at about 10-25°
grazing. This material is designed to provide about
-35 dB forward scatter loss at those angles from
18-40 GHz. The units must be installed back-to-back
in pairs to achieve the specifi ed performance.
• Type AEC-4/6-12T-MM is the same as Type AEC-4/5-
MM, but optimized for lower frequencies.
2/
Specifi cations
AEC-4/1-MM-HP AEC-4/6-12T-MM AEC-4/5-8T-MM AEC-4-MM
Overall height in 5 6 to 12 5 to 8 4
cm 12.7 15.2 to 30.5 12.7 to 20.3 10.2
Refl ectivity - 40 dB @ 18 GHz - 50 dB @ 12-40 GHz - 50 dB @ 12-40 GHz - 45 dB @ 18
Absorption @ dB - 50 dB @ 95 GHz Grazing @ 10° Grazing @ 10° 40 GHz
Normal Incidence - 35 dB @ 12-40 GHz - 35 dB @ 12-40 GHz
Weight per Sq. ft lbs 3.7 2.6 1.9 2.75
kg 1.7 1.2 0.9 1.25
Fire Protection Base NRL 8093 NRL 8093 NRL 8093 NRL 8093
Color Black Blue* Blue* Blue*
*Light color application over black
AEC-4/1-MM-HP mechanical drawing
24.0’
’ 24.0’
’
1.0’
’
5.0’
’