MODELING OF DISCRETE ORTHOGONAL CODE SEQUENCES FOR INFORMATION TRANSMISSION SYSTEMS
Andrey Studenikin, A.P. Zhuk
Abstract
The development of wireless information transmission systems with code division of channels, taking into account the specifics of their functioning, is associated with the generation and processing of complex signals with a wide frequency band of the spectrum and the required correlation characteristics, as well as with the use of special algorithms for information exchange. The problem of synthesizing ensembles of discrete orthogonal code sequences with minimal side peaks of correlation functions and having minimal dis placement of the amplitude-frequency spectra is relevant. Successful solution of this problem affects the quality of output information, noise immunity, and signal-to-noise level of the information trans mission system. The aim of the article is to synthesize an ensemble of discrete orthogonal code sequences for a wireless information transmission system with code division of channels, taking into account restrictions on energy, spectral and correlation characteristics. A variant of solving the problem of synthesizing ensembles of discrete orthogonal code sequences with minimal side peaks of correlation functions having minimal displacement of the amplitude-frequency spectra is to use the modeling method based on eigenvectors of diagonal symmetric matrices. The article presents a synthesized ensemble of discrete orthogonal phase-manipulated sequences with a volume of N = 16. The use of a synthesized ensemble of discrete orthogonal sequences as modulating sequences in wireless information transmission systems with code division of channels provides a gain in noise immunity in the case of narrow-band interference of fixed power. From the above, it can be seen that the resulting ensemble of discrete orthogonal code sequences exceeds the characteristics of the known systems of orthogonal code sequences and meets the requirements. The use of the proposed method for modeling ensembles of discrete orthogonal code sequences with improved autocorrelation and spectral properties for wireless information transmission systems with code separation of channels makes it possible to increase the noise immunity and efficiency of using the frequency range of these systems.