| 摘要 |
An acoustic surface-wave device is utilized to distribute coded samples of an information signal among a plurality of output ports. A first surface-wave transducer responds to signals from a source of time-domain information for launching acoustic surface waves in a piezoelectric substrate. The piezoelectric material is one which exhibits a non-linear relationship between an applied electric field and the strain developed by that field; alternatively, non-linear elements are included in the output circuitry. Either by reason of the dispersive nature of the transducer or by treatment of the time-domain signals before their application to the transducer, the surface waves propagate in one direction and exhibit a given mode of spatial dispersion along that path of propagation. A second surface-wave transducer responds to counterpart signals from another source to launch acoustic surface waves in the opposing direction which exhibit a mode of spatial dispersion that effectively is the conjugate of the aforesaid given mode. Finally, a plurality of output transducers are spaced successively along the propagation paths. The output transducers are individually responsive to respective different spatially-distributed combinations of the dispersion modes that all have the same frequency but which yield respective different output signals individually corresponding to respective different time-displaced portions of the information signal.
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