Research On Blind Channel Equalization For OFDM Based On UPF Algorithm

Orthogonal frequency-division multiplexing system (Orthogonal FrequencyDivision Multiplexing, OFDM) uses a superior performance of orthogonal subcarriersprinciple, can be very effectively attenuated signal multipath fading interference in thetransmission process, and because the sub-carriers may not overlap with each otherinterference, it is possible to use a very high operating efficiency of limited frequencybandwidth, because it makes this technology has been among the next generationmobile communication system has become the core of the underlying physicaltransmission technology.4G is a key reason for the3G can be substituted. Using theefficient channel estimation for OFDM systems can be adjusted for each subchannelinformation transfer rate of each subchannel maximum information transmission whileavoiding the communication capability of the communication bandwidth in the lowpart of the frequency decreases and the communication efficiency of the entire system.Among the particle filter to suppress noise and weaken the channel number ofeffective methods among its various performance is more superior. And has thepotential to continue to improve and space, there are good prospects for use in targettracking and state estimation.This paper discusses the particle filter algorithm in OFDM systems channelequalization is how to play a role, and an attempt to improve the program proposed toimprove the performance of particle filter method. The main contents are as follows:1. First, the decline from the beginning of wireless communication channelinterference, describes the characteristics and causes of each fading, for OFDMdecency below is how to overcome some of the interference based on the principles of good background; development, through the history of the development in the field ofcommunication about the history of OFDM against the background of its importanceand great role for communication technology, a detailed description of the variouscomponents of the OFDM system, on the basis of the various parts of the system arediscussed how the pieces fit together to complete a highly efficient transmission ofinformation, analyzes its working principle in the advantages and disadvantages of theoperation mechanism of its own because of the formation.2. The detailed analysis of the channel estimation and equalization for OFDM systemsperformance improvement principles and effects, and incidentally referral channelestimation algorithms classification, advantages and disadvantages, leads to theparticle filter. Numerical methods embodied theory of probability and statistics fromMonte Carlo methods based, through Bayesian filtering-Learn "predict correction" ofthe iterative process, the particle filter relevant content analysis and presentation, andfinally launched based on particle Filtering OFDM system channel blind equalizationalgorithms basic processes; and made clear that a number of methods to enhance theperformance of the filter, select the proper function of the importance of appropriatealgorithms can significantly improve the performance of particle filter.3. Use the standard particle filter algorithm to estimate the various parameterscalculated channel state, the results obtained in terms of their degree of accuracy thereis room for improvement for further improvement. Another comparison of differentmethods-unscented Kalman filter (UKF) algorithm and regularization child. Particlesfrom the particle sample extraction section space generated by the two algorithms, thebinding to the particle sample space UPF algorithm generated. By combining with thesample particle space to achieve the advantages of the combination of these two algorithms to UPF algorithm.