Some remarks on propagation characteristics of ridge guides for acoustic surface waves at low frequencies
Some remarks on propagation characteristics of ridge guides for acoustic surface waves at low frequencies
复制标题
关于低频声表面波脊波导传播特性的几点思考
DOI：
--
复制
发表时间：
1974
期刊：
影响因子：
--
通讯作者：
B. Sinha
中科院分区：
文献类型：
--
作者：
B. Sinha
求解了弹性理论的平面应力方程，预测了无限高脊波导在低于薄板最低厚度剪切频率下的弯曲模式和伪瑞利模式的传播特性。在上述极限情况下，前一模态的抛物色散特性与迄今为止发表的结果有明显的偏离。这种巨大的差异是由于脊中弯曲型运动和相邻自由基底所能承受的唯一瑞利型扰动不相容造成的。这将导致表面波能量的不良辐射进入基材的主体，并负责截止频率由几个作者获得。讨论了由此产生的对这种波导有效工作范围的影响。发现后一种模式在直流下的非色散速度比微波网络结果低1.5%。
The plane‐stress equations of the theory of elasticity are solved to predict the propagation characteristics of flexural and pseudo‐Rayleigh modes of infinitely tall ridge guides for frequencies lower than the lowest thickness‐shear frequency of thin plates. The parabolic dispersion characteristic of the former mode shows appreciable departure from the hitherto published results in the above limiting case. The large discrepancy is due to the incompatibility of the flexural type of motion in the ridge and the only Rayleigh type of disturbance that the adjoining free substrate can sustain. This causes undesirable radiation of the surface wave energy into the bulk of the substrate and is responsible for cutoff frequencies obtained by several authors. The consequent implication for the useful operational range of such waveguides is discussed. The nondispersive velocity of the latter mode at dc is found to be 1.5% lower than a microwave network result.