Two−port cavity resonator low−insertion−loss delay line

A delay line is described which uses unidirectional transducers, formed by placing a short interdigital transducer (IDT) adjacent to a grating reflector, to realize low insertion losses. Theoretical and experimental results are compared for a device with 10.5 finger pair transducers and 100 finger pair gratings. The measured insertion loss was 2.5 dB at 38.14 MHz.