RESEARCH SPECTRAL EFFICIENCY OF NEW MODULATION FORMATS IN FIBER-OPTIC NETWORKS

The rapid growth of the use optical technologies requires the development of methods and means to improve the spectral efficiency and noise immunity of fiber-optic networks when using wavelength multiplexing. On the basis of the research a new approach to the construction of the method of calculation spectral efficiency indices of new modulation formats in fiber-optic networks has been developed. The proposed method calculation of indicators takes into account the efficiency indicators fiber-optic transmission systems, the algorithm demodulator synthesis and effective methods modulation formats such as M-ary Quadrature Amplitude Modulation, Differential Phase Shift Keying and M-ary pulse position modulation. On the basis of the calculation method, important analytical expressions evaluating the characteristics of line capacity and noise immunity of optical signal reception are obtained.