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To reduce the level of intersymbol interference and interchannel interference, it is proposed to form the transmitted signals using the basis functions obtained by shifting the impulse responses of linear systems by multiple time intervals. An algorithm for calculating the weight of the orthogonality of basis functions is proposed. A criterion for the existence of the indicated weight of orthogonality is formulated.

The article deals with analysis of the causes of intersymbol interference and interchannel interference. It is indicated that physically unrealizable orthogonal bases are used to describe systems and signals. The considered interference occurs due to the loss of orthogonality by the coordinate signals of the bases. Known methods for obtaining systems of orthogonal functions do not allow the formation of a coordinate basis corresponding to physically feasible systems and signals. It is proposed to use equidistant biased impulse characteristics of physically realizable linear systems as basic signals. An orthogonalization method based on determining the weight of orthogonality is described. It is shown that the resulting basis is quasi-orthogonal. It is determined that the conversion of the standart low-pass prototype filter into the filters of channel-forming equipment does not change the conditions of orthogonality. Structural schemes of a modulator and a demodulator of two-dimensional signals are proposed, based on the developed method of orthogonalization.

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Broadband data transmission systems are used noise-like signals derived from pseudorandom sequences. The most widely used m-sequences have good correlation properties. However, M-sequences are not orthogonal sequences. In this work the methods of creation of orthogonal bases on the basis of M-sequences are proved. Two theorems on the linear independence of the functions obtained by cyclic shift of some of the original discrete functions are provide. For orthogonalization of M-sequences, the method of orthogonalization is used, which consists in determining the weight of orthogonality of linearly independent functions.