| 摘要 |
An acoustic surface wave device employing an input and an output transducer (2, 3) and a multistrip coupler (5). The input and output tracks (11, 12) are separated to avoid unwanted acoustic energy transfer. As a result, a significant loss can occur from the launching of acoustic energy from the interconnecting conductors of the msc. The interconnecting conductors (22, 32') of the multistrip coupler are spaced differently from the, or the equivalent, wide-aperture beam spacing of conductors (16, 17; 36', 37') in either track of the msc so as not to launch any acoustic surface or bulk waves within the frequency passband. In a forward transfer msc different spacings can alternate, and in a reflective msc the spacing can take the mean of the respective equivalent wide-aperture-beam spacings of the coupler electrodes. In a reflective msc, to overcome spurious responses due to acoustic reflection from one track to the other, especially when single guided mode transducers are employed, the connecting strips (32') are inclined to the perpendicular to the propagation direction.
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