Communications: directive radio wave systems and devices (e.g. – Radio wave absorber
Patent
1997-10-01
1999-02-16
Lobo, Ian J.
Communications: directive radio wave systems and devices (e.g.,
Radio wave absorber
H01Q 1700
Patent
active
058725342
ABSTRACT:
An electromagnetic wave absorber, having two or more magnetic layers for broadening the reduced reflectivity frequency bands, and formed of materials with staggered magnetic dispersion loss spectra. A high permeability nickel-zinc ferrite, rich in zinc, e.g., 0.7 molZn, 0.3 molNi is used as a reference absorber layer adjacent to a ground plane. The successively higher frequency spectra are related to the outer layers and the successively higher loss spectra are achieved by using higher magnetization soft ferro or ferrimagnetics, higher anisotropy semi-hard or hard ferro-ferrimagnetic material, or synthesized "smart" materials, for simulating magnetic loss dispersion. The successive layers are decoupled one from another by any of electrical, magnetic, and/or structural arrangements. The decoupling may be implemented by a significant difference in the frequencies at which the maximum values of the magnetic loss vs. frequency occurs for each layer. Alternatively, the decoupling may be implemented by a significant difference in the optical index of the material in each layer in a decreasing order towards the outside. Also, the decoupling may be implemented by the intercalation of higher wave impedance and low optical index layers increasing the apparent wave impedance presented from one to the next magnetic layer. Using these implementations the wave-absorber frequency range may be extended from about 30 MHz to 3 GHz and above.
REFERENCES:
patent: 5276448 (1994-01-01), Naito et al.
patent: 5323160 (1994-06-01), Kim et al.
patent: 5708435 (1998-01-01), Kudo et al.
Budzyn Ludomir A.
Casella Anthony J.
Fair-Rite Products Corporation
Hespos Gerald E.
Lobo Ian J.
LandOfFree
High frequency broadband absorption structures does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with High frequency broadband absorption structures, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and High frequency broadband absorption structures will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2066033