Single and coupled MSW resonators for microwave channelizers

Magnetostatic-wave (MSW) resonators using epitaxial single-crystal yttrium iron garnet (YIG) films have been integrated to form a channelizer operating in the microwave frequency range. The microwave signals are coupled to and from the resonators using microstrip structures. This approach to frequency sorting has the advantage of relatively low insertion loss (less than 6 dB for single resonators), and only a uniform bias magnetic field is needed. This approach has been used to enhance the bandwidth and improve the filter response of each channel. Channel 3-dB bandwidths were increased from 4-5 MHz (for single-resonator channels) to more than 10 MHz by implementing coupled resonators. Experimental results describing the characteristics of single and coupled MSW resonators are presented