| 摘要 |
PURPOSE:To make it possible to obtain required amplitude, phase and center frequency characteristics by varying the amplitude and polarity of a voltage applied to each electrode finger by providing several electrode fingers within one wavelength. CONSTITUTION:On substrate 11, the n-number conductive electrode fingers 12 are arranged at intervals of distance (d) and within one wavelength, there are not less than two electrode fingers. Circuits (a1, a2...an) 13 are connected to respective electrode fingers. Those circuits 13 operate so that a voltage will be applied to each electrode finger 12 by varying the amplitude and polarity of a signal from signal source 14. Here, the amplitude and polarity of the voltage applied to each electrode finger 12 are the Fourier inverse transform of needed frequency characteristics, i.e. impulse response. |
