Design and performance of SAW low insertion loss filters (Ⅱ) Transversely-Coupled Resonator Filter

Currently the mobile communication system has a great need of the filter with narrow bandwidth,low loss and high rejection.SAW transversely-coupled resonator filter (T CRF) is t he optimum physical implementations of the filter above mentioned.In this papert we first analyzed theoretically TCRF using Coupling-of-Modes model presented by Chen & Hartmann et al.The experimental resultsof the filter fabricated on ST Quartz substrate is given.The device achieved favorable characteristics with an insertion loss of 2.7 dB,a sidelobe rejection of about 60 dB,a fractional bandwidth of about 0.5% and a very flat passband.