The filter consists of an apodized bidirectional and an unapodized group-type unidirectional transducer. The unidirectional transducer is designed to take different finger pairs between sending and reflecting electrodes for extension of the impedance matching range. A thin-film capacitor monolithically fabricated on a 128 degree Y-X LiNbO//3 substrate is used as a phase shifter. Low insertion loss of 11. 3 dB with no adjustment for impedance matching can be achieved without increasing chip size and number of components.