Research On Decision Feedback Equalization In Single Carrier Based On Fractional Fourier Transform Domain

In wireless broadband communication system, usually it exists inter-symbol interference(ISI) caused by multipath propagation. An effective program against channel multipathpropagation is single-carrier frequency domain equalization (SC-FDE). However, anytechnology is not perfect. When channel have a frequency deep decay point, SC-FDEtechnology also exists its defects. Because the fractional Fourier transform is a generalizedform of the ordinary Fourier transform and fractional Fourier transform order flexibility. Sothe fractional domain equalization for single-carrier need to select the channel characteristicsmatches the order of to achieve than the single-carrier frequency domain equalization bettereffect.First, the article provides an overview of single-carrier frequency domain equalizationtechnology overview of the development and Fractional Fourier Transform applications incommunication systems Research. Second, the article describes a single-carrier frequencydomain equalization technology classification and basic principles, and comparative analysisof the theoretical performance of OFDM technology. Finally, it describes the fractionaldomain equalization of single carrier system structure, and the definition and nature of thefractional Fourier transform.This study a noise prediction decision feedback equalization structure, it compared withthe conventional decision feedback structure, both the same in BER performance, but theformer are significantly reducing in the computational complexity. Due to Noise predictiondecision feedback having this advantage, this paper gives the derivation of fractional domainequalization coefficients based on the form of matrix operations, this method is more simple,to avoid the tedious calculation process. In addition, considering the effect of randommultipath fading wireless communication, this article makes Fractional domain noiseprediction decision feedback equalization structure used in the encoding system. Frequencydomain equalization using packet interleaving simulation comparison, results show that incoding system the fractional domain equalization does not require additional signalprocessing can get better than frequency domain equalization performance.This paper studies a fractional domain equalization based on a unique block structure.Taking into account the fractional Fourier transform computing complexity problem, we take advantage of the unique word UW does not contain any useful data nature of the informationto be balanced with the useful data at the receiving end before dealt with separately, and thengives a calculation approximation method of the equalizer coefficients. Thus simplifying theequalization process, and also so that the amount of arithmetic operation has been reduced.