Modern types of modulation with extended spectrum in multiservice telecommunication networks

An analysis of the prospects for the development of MIMO standards is presented. It is shown that the MU-MIMO specification is one of the most significant technological improvements to MIMO. At present, the standardization of mobile communication technologies to lay the foundations of wireless networks 5G, there is a general view of the need to replace the fundamental OFDM technology at the expense of more efficient, which can better operate in 5G conditions. For this purpose, a number of new forms of modulation have been introduced. It should be noted that at the same time, these methods have a basic principle of OFDM technology. The main idea of OFDM technology is to divide the frequency selective channel into a number of narrowband sub-channels. In these subchannels or subcarriers, orthogonal narrowband signals are transmitted in parallel. Since each of these signals undergoes shallow fading, then a fairly simple scalar correction of the channel. The main methods of promising technologies UF-OFDM, FBMC, and GFDM are described, which are logical continuation of OFDM-modulation development. In many ways, FBMC has much in common with CP-OFDM and OFDM, which use a cyclic prefix as a security signal. GFDM is a flexible multi-carrier transmission method, which is largely similar to OFDM. UF-OFDM uses filtering to provide its unique characteristics.