I.V. Kuznetsov - Dr. Sc. (Eng.), Associate Professor, Department of Telecommunication Systems, Ufa State Aviation Technical University E-mail: tks@ugatu.ac.ru G.S. Voronkov - Senior Lecturer, Department of Telecommunication Systems, Ufa State Aviation Technical University; Deputy Technical Director of LLC «TehKom» (Ufa) E-mail: voronkov.gs@net.ugatu.su A.Kh. Sultanov - Dr. Sc. (Eng.), Head of Department of Telecommunication Systems, Ufa State Aviation Technical University E-mail: tks@ugatu.ac.ru V.V. Antonov - Dr. Sc. (Eng.), Head of Department of Automated Control Systems, Ufa State Aviation Technical University E-mail: Antonov.v@bashkortostan.ru

The article researches a problem of telecommunication systems based on OFDM energy efficiency increasing. It is proposed to reduce the dynamic range of the I and Q channels complex envelopes due to a new method of conversion - differential OFDM-conversion. The method distinctive feature lies in the fact that at each stage as a modulating signal in high-frequency modulation the difference between the real and the predicted signal value in the quadrature channels is proposed to use. Predictor unit parameters are transmitted simultaneously using secondary multiplex channels. An important requirement in this case is to maintain a orthogonality or quasi-orthogonality of quadrature channels. Coordination and prediction unit mathematical model is given in the article. The model is based on the consideration of linear prediction operation. It is shown that the model can be obtained from the solution of the modified Wiener - Hopf equation at known power spectral density (PSD) of the signals of the quadrature channels and interference current in the communication line. The example showing the efficiency of the proposed method is given. The suggested method application for transcendental functions is shown. Conclusions are given.

 

1. LTE for UMTS: OFDMA and SC-FDMA Based Radio Access / Edited by Harri Holma and Antti Toskala. John Wiley & Sons, Ltd. 2009. ISBN: 978-0-470-99401-6.
2. Fundamentals of 5G Mobile Networks / Edited Jonathan Rodriguez. John Wiley & Sons, Ltd. 2015. ISBN: 978-1118867525.
3. ITU-R M.2047-0. Detailed specifications of the satellite radio interfaces of International Mobile Telecommunications-Advanced (IMT-Advanced).
4. Federalnyjj zakon «Ob ehnergosberezhenii i o povyshenii ehnergeticheskojj ehffektivnosti i o vnesenii izmenenijj v otdelnye zakonodatelnye akty Rossijjskojj Federacii» ot 23.11.2009 № 261-FZ.
5. Ayman Radwan. Energy Efficient Smart Phones for 5G Networks. Springer. 2015. ISBN: 978-3319103136.
6. Alagoz F., Gur G. Energy efficiency and satellite networking: A holistic overview // Proceedings of the IEEE. V. 99. № 11. 2011. P. 1954−1979.
7. Kuznecov I.V., Sultanov A.KH. Koordinirovannoe upravlenie dinamicheskimi obektami v slozhnykh tekhnicheskikh sistemakh.  Ufa: Ufimskijj gosudarstvennyjj aviacionnyjj tekhnicheskijj un-t. 2012. 207 s.
8. Cejjtlin JA.M. Proektirovanie optimalnykh linejjnykh sistem. L.: Mashinostroenie. 1973. 240 s.