Electrically cascaded surface-acoustic-wave resonator filters

Abstract

Three nearly identical surface-acoustic-wave resonator filters at ≃ 35 MHz have been fabricated with aluminium metallisation on yz LiNbO3 substrates. The filters are electrically cascaded to yield a combined frequency response that exhibits 80 dB sidelobe suppression, Q ≃ 3000, no spurious responses in the range 1–500 MHz and an insertion loss in a 50 Ω system of only 13 dB.