Originally for the solution of elastic structure the matrix (I-R)-1 is expanded into Neumann series to circumvent the difficulty of singularity in reversing the matrix in the frequency domain.

• 回传波射矩阵法在应用于弹性结构时，为了避免频域里矩阵求逆的奇异性，求解时对矩阵(I-R)-1采用牛曼级数展开;