| 摘要 |
PURPOSE:To obtain required frequency characteristics precisely by setting an oscillation source close to an oscillation source making an inter-digital electrode maximum cross width to zero and forming another inter-digital electrode provided with a remaining oscillation source arranged by electrically floating or thining an electrode finger included in the zero oscillation source. CONSTITUTION:Input/output side inter-digital electrodes 21, 22 are formed on a surface wave substrate 20 at a prescribed distance. The electrode 21 is constituted by the 1st and 2nd inter-digital electrodes 23, 24. The electrode 23 is weighted at its cross width so as to be inclined at the right and left of an oscillation source 23c making an envelope to the maximum cross width by shifting and dispersing a zero oscillation source 23d in the length direction of the electrode finger on the basis of impulse response regulating an even component. Although regulating an odd component, the electrode 24 sets an oscillation source located close the oscillation source 23c so as to be zero and thins the electrode finger constituting the zero oscillation source to omit the electrode finger, so that oscillation sources other than the zero oscillation source can be arranged in the vicinity of the position maximizing the oscillation intensity in the length direction of the electrode finger. |
