System applications of magnetostatic wave devices

A need for microwave signal processing components ranging from simple delay lines to broadband, complex analog non-recursive transversal filters has led to the exploration of several solid-state technologies. Bulk acoustic delay lines lack spatial signal tapping and have high insertion loss. Electromagnetic delay lines have high insertion loss, limited signal processing capabilities, and are bulky. Surface acoustic wave (SAW) devices offer excellent signal processing capabilities at VHF/UHF but suffer from excessive loss at microwave frequencies and the requirement for transducers of sub-micron linewidths. However, a signal processing technology based on magnetostatic waves (MSW) propagating on epitaxial yttrium iron garnet (YIG) is emerging to fill microwave signal processing requirements. This paper summarizes the characteristics and status of magnetostatic waves and devices based on MSW, and initial experimental studies of the application of MSW devices to systems, and presents a survey of other potential areas of MSW device applications.