An OFDM System Of PAPR Reduction Method Based On Wavelet Transform

OFDM technology is used to realize the effective,high-speed transmission of information,has been applied in many fields,such as wireless,digital broadcasting,it as the key technology of 4 g and attention.In DFT-however,it is a key problem of OFDM is the signal with a higher PAPR values,this for the development of the OFDM system is a very big restrictions.In the field of signal processing and the fast Fourier transform is also another kind of transformation is of great practical discrete wavelet transform,it has a better time and frequency domain local features,this is the Fourier transform is very difficult to reach the standard.There are also many orthogonal wavelet function,it can replace the Fourier transform of orthogonal basis for data transformation process,so in the field of digital,image processing,wavelet transform has an irreplaceable role.This article USES wavelet transform instead of the traditional Fourier transform,the first analysis of the PAPR values after Fourier transform and wavelet transform of the distribution of PAPR values,then the wavelet transform to new clipping technology of data processing,after get PAPR after limiting value,compared with the two again,come to the conclusion.First of all,this article simply introduces the OFDM technology and the principle of wavelet transform,and then through the experimental simulation of traditional OFDM system based on IFFT/FFT technology some methods of reducing PAPR values mainly limited of such technology,selective mapping,part of the three ways of transmission sequence.Analysis of their experimental data,and compared with the original did not use these methods,comparing the distribution of PAPR values experimental results are obtained.Then,in order to improve the front based on Fourier transform the distribution of the PAPR of OFDM technology,this paper developed a new method for effectively reduce PAPR values of experiment,this method is combining wavelet transform technique and OFDM systems.Can see from the results of the distribution of PAPR values relative to much better use IFFT/FFT technology,the effect of using different wavelet base is different.This article finally adopted mainly three kinds of wavelet: Haar wavelet,Daubechies wavelet,wavelet and Symlet draw out the several experimental results of wavelet reduce PAPR values figure,and the corresponding analysis was carried out on the map.Finally,it is the innovation of this article,also is the patent,that is to use Matlab code and simulation in the powerline channel simulation environment,this paper developed a new clipping algorithm,wavelet transform technology and for the first time the new clipping algorithms to reduce the PAPR values associated with the simulation experiment.Results show that the new clipping algorithm to reduce PAPR values relative to the front of the effect of several kinds of algorithm is relatively ideal,image analysis,is given below.