Shkulipa P. Synthesis of the signals for telecommunication systems with correlative encoding

The study object: formation of and processing upon narrow-spectrum signals in correlative coding systems. The changes in spectrums of resulting digital streams with the process duration increasing are observed. The block diagrams given explain formation, transmission and registration of signal sets suggested. The study subject: methods of synthesis of signals with controlled intersymbol interference (ISI) in telecommunication systems. The study methods: linear algebra, theory of approxima-tion and wavelet analysis, Fast Fourier Transform (FFT), mathematical modelling in Matlab. The objectives of this thesis are to develop method of synthesis of signals with controlled ISI and design an appropriate device that will implement this method. Novelty: The generalized Haar wavelets are proposed as an orthonormal basis for approximation of signals with controlled ISI. For the first time, an optimal low-pass smoothing filter (LPF) that minimizes residual ISI is proposed. It is proven that application of Butterworth LPF filters is reasonable. The parameters required for their optimal operation are also given. For the first time, a method that enables analyzing spectrum characteristics of digital streams with controlled ISI is proposed. Main conclusions of this thesis are corroborated by two patents in Ukraine. They are "Спосіб передавання цифрової інформації" (methods of digital data transmission) and "Спосіб передавання цифрової інформації сигналами з компактним спектром" (digital data transmission via narrow-spectrum signals). Study results are introduced in A.S. Popov Odessa National Academy of Telecommunications for study and further research.