The main points of this paper were- the table of the phase-shift factors, the variation of the continuation step length and the technique of the two-dimensionalfiltering.
重点介绍了提高执行效率所采用的相移因子造表，变延拓步长，二维滤波等几种方法和试验结果。
2
Improvement to the old method formulated in this paper mainly lies in the combination of phase displacement method with frequency two-dimensionalfiltering in making operation.
本文对原方法的主要改进点是把相位移法与频率域二维滤波结合在一起进行运算。
3
This paper discusses the two methods for suppression of. multiple waves, namely, coherence emphasis method and twodimensionalfiltering method.