A magnetostatic wave signal-to-noise enhancer

Abstract

A new type of frequency selective signal-to-noise enhancer is described, which shows instantaneous bandwidths of more than 800 MHz at frequencies up to 4.2 GHz. The device consists of an epitaxial YIG film in contact with a narrow microstrip transmission line. Magnetostatic surface waves in the YIG film act as saturable absorbers of power from the microstrip line. Using a 26.6-μm-thick YIG film on a 23-μm-wide microstrip line of 21 mm length, resulted in a small signal (<−6 dBm) attenuation of in excess of 25 dB. The attenuation was reduced by 15 dB when the input power was increased to +10 dBm.