Research And Implementation Of Papr Suppression Technology Based On IM-DDO-OFDM System

With the rapid growth of data services,increasing requirements for timeliness and reliability of data transmission are required.As an efficient data transmission method,OFDM systems is able to transmit high-speed data streams on multiple orthogonal subcarriers,so it has strong resistance to delay expansion which can greatly improve spectral efficiency.However,due to the overlapping of various subcarriers,OFDM system usually has a peak-to-average power ratio(PAPR)problem,which requires power amplifiers to operate within a larger linear range,leading to the increasing complexity and higher cost of system implementation.However,most of the proposed schemes of peak-toaverage power ratio suppression have high computational complexity and latency,and involve many multiplication operations,which cannot be well applied to FPGA implementations of real-time OFDM systems.Therefore,focusing on the modulation and demodulation parts of OFDM system,it is very necessary to propose an improved peak-to-average power ratio suppression module and design the corresponding real-time transmission system according to the module.The main content and related results of this article are as follows:1.A peak-to-average power ratio suppression module based on an improved partial transmit sequence scheme is designed.And the implementation of each part of the module is completed.Compared to traditional partial transmit sequence schemes,this scheme has lower computational complexity.The LUT resource usage is reduced by up to 36.95%,and the FF resource utilization is reduced by 38.77%for the development board.2.The FPGA scheme of the DFT-s-OFDM generation and demodulation module is designed.The function of each DSP module in the scheme is realized and verified by simulation.Compared with the PTS-based peak-to-average power ratio suppression module,the implementation of this module does not require the transmission of extra sideband information.3.A baseband IM-DDO-OFDM real-time transmission system which is compatible with two schemes mentioned above is designed.The parts of the transmitter and receiver are realized.As is shown in the experiments,compared with traditional IM-DDO-OFDM systems,the suppression effect of the peak-to-average power ratio in the realized system is improved by nearly 3dB.