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利用Ｓｈａｍｗａｙ和Ｄｅｒ的多道最大或然性反褶积原理，讨论了从单台三分量远震Ｐ波波形中分离接收函数径向与垂向分量复谱比的方法．根据Ｔａｒａｎｔｏｌａ的波形反演理论发展了接收函数复谱比的非线性反演方法．本文的反演方法除了拟合接收函数的复谱比之外，还需拟合时间域中接收函数垂向与径向分量的初至振幅比．合成波形数据反演的结果表明本文方法的反演结果不依赖初始模型．利用该方法和ＣＤＳＮ台网兰州台记录的宽频带远震Ｐ波波形数据，研究了该台站的接收函数及其随方位角的变化．接收函数复谱比非线性反演给出了该台站下方１４０ｋｍ深度岩石层的Ｓ波速度结构，得到兰州台下方地壳厚度为５４ｋｓ，岩石层厚度为９４ｋｍ．
Using the multi-channel maximum likelihood deconvolution principle of Shamway and Der, the method of separating the spectral components of the radial and vertical components of a receiver function from a single three-component teleseismic P-wave waveform is discussed. According to Tarantola ’s waveform inversion theory, a nonlinear inversion method for the complex spectral ratio of receiver functions was developed. The inversion method in this paper needs to fit the first-arrival amplitude ratio of the vertical and radial components of the receiver function in the time domain in addition to the complex spectral ratio of the received function. The results of the inversion of synthetic waveform data show that the inversion results of this method do not depend on the initial model. Using this method and the broad-band teleseismic P-wave data recorded at Lanzhou station of CDSN network, the receiver’s reception function and its variation with azimuth angle are studied. The S-wave velocity structure of the 140km-depth lithosphere below the station is given by the complex spectrum of nonlinear response function. The crustal thickness beneath the Lanzhou platform is 54ks and the rock layer thickness is 94km.