Kyocera Corporation

Yuriko Nishimura

Tetsuya Kishino

Kiyohiro Iioka

Tsuyoshi Nakai

Masahisa Shimozono

Shigehiko Nagamine

A branchingfilter has an antenna terminalwhich receives signal waves and disturbance waves, a transmission filterwhich is connected to the antenna terminal, a reception filterwhich is connected to the antenna terminaland receives a portion of the signal waves and has, as a passband, a frequency range higher than a passband of the transmission filter, and a disturbance wave resonator which is connected to the antenna terminaland to the ground and positioned closer to the antenna terminalside than the transmission filterand the reception filter. The disturbance wave resonatoris connected to antenna terminalat a position closer to the antenna terminalside than the transmission filterand the reception filter. A resonance frequency of the disturbance wave resonatoris within a frequency range smaller than the passband of the transmission filter and includes a frequency range of the disturbance waves.

Duplexer and communication module

A surface acoustic wave elementincludes an IDT electrodehaving an electrode fingeron a piezoelectric substrate. The electrode fingeris formed by laminating an intermediate layerand an electrode layerhaving a higher coefficient of thermal expansion than that of the intermediate layer. The electrode fingerhas a cross section of a trapezoidal shape that widens nearer to the piezoelectric substrate. An angle &#x3b1;formed with a side surface of the intermediate layeris formed larger than an angle &#x3b2;formed with a side surface of the electrode layer

Growing community of inventors

Kyoto, Japan

Yuriko Nishimura