Multi-band fractal microwave absorbers

Abstract

Multi-band fractal microwave absorbers are proposed to operate within the UHF-RFID band and/or the GSM frequency bands. The miniaturization capabilities offered by the adopted fractal geometry are exploited to design multi-band absorber unit cells having small size (less than half-wavelength) and a very thin substrate thickness (≤λ0/100 at the operating frequency). Thanks to its compactness and effectiveness in achieving perfect absorption, the proposed configuration is appealing for multipath reduction in confined indoor environments or for multi-band electromagnetic interferences suppression in low-frequency communication systems.