Research On Controlled Trimming Iterative Algorithm For Suppressing Peak-to-Average Power Ratio In OFDM Systems

Orthogonal Frequency Division Multiplexing(OFDM)technology is a high-speed parallel multi-car:rier transmission scheme.It is one of the most populartechnologies in the fourth generation of mobile communication systems.It has strong anti-fading and anti-symbol.interference.Since the superposition of multiple carriers causes the signal peak to be too large,the phenomenon that the peak-to-average power ratio(PAPR)is too high,which requires the system transmit power amplifier to have a high linear range or power back-off.At the same time,the complexity of Analog to Digital Converter(ADC)and Digital to Analog Converter(DAC)is increased,which reduces the efficiency of the entire system.In view of this,this paper studies the peak-to-average power ratio suppression technique in OFDM system,and focuses on the analysis of signal scrambling code technology.The selective mapping method and partial transmission sequence method have higher computational complexity and need to transmit sideband information.The reserved subcarrier method is simple to implement and does not require the transmission of sideband information.However,the problem of reserved subcarrier method to reduce the peak-to-average power ratio is attributed to the optimal solution to minimize the problem,which leads to the problem of high computational complexity.Aiming at this problem,this paper proposes a controlled pruning iterative algorithm based on the idea of reserved subcarriers and low complexity.According to the actual project requirements,an OFDM communication system was designed,and the controlled pruning iteration algorithm was applied to the self-developed system to suppress the peak-to-average power ratio.The performance of the algorithm suppression effect is simulated by MATLAB tool.The result verifies the correctness and feasibility of the algorithm.The integrated simulation results and computational complexity show that the controlled pruning iterative algorithm is more suitable for self-developed OFDM systems,and the algorithm is verified in the OFDM system.VWhen the complementary cumulative function(CCDF)is 10-2,the system peak is reached.The average power ratio is reduced by 1.3dB,which satisfies the design requirements of the system.