The length of Sound Barrier built on highway is limited usually.How to calculate diffracted attenuation accuratly in this case is the important part of sound barrier design.

• 摘要公路上设置的声屏障的长度一般为有限长，如何准确的计算出此种情况下声屏障的绕射衰减，是声屏障声学设计的关键。