Research On Reducing The Peak-to-Average Power Ratio In Multi-Carrier Systems

Multicarrier communication technology is usually applied to the high speed data transmission in the telecommunication system. It can resist frequency selective fading and is high frequeccy efficiency. Meanwhile, multiple-input-multiple-output (MIMO) system architecture makes it possible to increase system capacity and improve data transmission speed and system transmission quality. Consequently, they become key technologies in the new generation telecommunication system. Multicarrier communication system with MIMO technology can provide wider covering area, better transmission quality and achieve higher data transmission speed and frequency efficiency. However, the high peak-to-average power ratio (PAPR) problem of multicarrier communication technology seriously affected its realization and this problem was studied.At first, the basic principle of multi-carrier systems was introduced, the model of the Orthogonal Frequency Division Multiplexing system and the advantages and disadvantages of the system were given, and the conventional PAPR reduction of methods was introducted in the dissertation. Secondly, the technical program that using probability technology to reduce the PAPR was analyzed, and some changes to the traditional partial transmit sequence (PTS) program was made. Compared with traditional method, the method was better, number was less in searching, not all the values needed been traversed, but the system was more complex. The program that used the technology of the nonlinear compression and expansion to inhibit PAPR was analyzed, the deficience of the traditional technology of the compression and expansion was analyzed, and briefly introduction to the multi-carrier jamming technology was conducted. In order to reduce the multicarrier signal PAPR in the situations of equal gap relations and the unequal gap relations in multi-carrier jamming carrier, the Narahashi program and the revision plan that based on compensated the signal and the method of Newton and the method of masking time were separately uesd. Finally, the relative research and simulation about the whole paper is summarized, meanwhile, the further practical research is expected.