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The analysis of peculiarities of trachea wall structure is conducted. Possible mechanisms of its excitation are discussed. The acoustical and mathematical models of trachea with elastic walls are developed. These models foresee the possibilities of kinematic excitation of the upper end of trachea and propagation of an elastic wave along the trachea wall. In the wide frequency range a quantitative analysis of modulus and phase of the oscillatory velocity of the trachea elastic wall is performed. These data are compared with those obtained for the acoustical mode! of trachea with locally responding walls. It is shown that the elastic wall behaves as a delay line, and an elastic wave can propagate along this line in the range of low frequencies (f < 500 Hz), having the speed about 10 &div; 20 m/sec. At higher frequencies the elastic wall behaves like a locally responding surface. It is shown that even relatively low levels of kinematics excitation of the upper end of trachea cause significant changes in the character of frequency dependence of the trachea wall oscillatory velocity. The analysis of the frequency dependencies of oscillatory velocities of the first seven annular cartilages of the trachea wall is performed. It is found that their levels diminish with the increase of the distance of cartilage from the upper end of trachea. The relatively simple technique allowing to estimate real values of the transmission function of the oscillatory velocity from vocal chords to the upper end of trachea is proposed. [ABSTRACT FROM AUTHOR]