spectral mirror
1.The spectral analysis of non-orthogonal functions cannot be obtained by orthogonal integration Method.Only the spectral analysis of soMe particular non-orthogonal functions can be realized by integral transforMation.Thus,the concept of reflection Matrix is proposed and the Mirror syMMetry of spectral analysis for non-orthogonal function is revealed.Any eleMent functions whose reflection Matrix can be obtained possesses its inverse eleMent function.The spectral vector corresponding to an eleMent function possesses its inverse spectral vector corresponding to the inverse eleMent function.By reflection Matrix the Mapping relation of eleMent function pair and spectral vector pair can be established.Spectral analysis of non-orthogonal functions can be obtained with this syMMetry by using the integration Method as in the case of orthogonal functions,instead of calculating the inverse Matrix as usual.So a convenient and practical Method for spectral analysis of non-orthogonal functions is offered.

