公开(公告)号：US4764701A

公开(公告)日：1988-08-16

申请号：US947655

申请日：1986-12-30

申请人： Michael J. Garbacz ,  Kai Hansen

发明人： Michael J. Garbacz ,  Kai Hansen

IPC分类号： H03H9/145 ,  H04N7/167 ,  H01L41/08

CPC分类号： H03H9/72 ,  H03H9/02779 ,  H03H9/14567 ,  H04N7/167 ,  H03H9/1452 ,  H03H9/14547 ,  H03H9/1455 ,  H03H9/14552

摘要： A multichannel surface acoustic wave encoder/decoder having a common electrical input is designed so that the insertion losses of the channels differ despite the apparent design constraint of closely matched channel output impedances. The input transducing device or SAW transmitter is divided into individual transducers (or into subtransducers) having different numbers of finger overlaps, thus achieving different acoustic output levels which in turn result in different insertion losses for different channels. The finger spacing of the SAW transmitters can differ between the respective input transducers or subtransducers so as to optimize the center frequency of each channel.

摘要翻译： 设计具有公共电输入的多声道表面声波编码器/解码器，尽管存在紧密匹配的通道输出阻抗的明显设计约束，但是通道的插入损耗也是相同的。 输入转换装置或SAW发射器被分成具有不同数量的手指重叠的单个换能器（或者变换器），从而实现不同的声输出电平，这又导致不同通道的插入损耗不同。 SAW发射器的手指间距可以在相应的输入换能器或副传感器之间不同，以便优化每个通道的中心频率。