Investigations on channel equalization Techniques for coded modulation Systems

Abstract

newlineThe growth in communication services during the past five decades newlinehas been phenomenal Satellite and fiber optic networks provide high speed newlinecommunication services around the world Most of the wire line newlinecommunication systems are being replaced currently by fiber optic cables newlinewhich provide extremely high bandwidth and make possible the transmission newlineof a wide variety of information sources including voice data and video newlineWith the unimaginable development of Internet technologies efficient highspeed newlinedata transmission techniques over communication channels have newlinebecome a necessity of the day As the rate of the data transmission increases newlineto fulfill the needs of the users the channel introduces distortions in data One newlinemajor cause of distortion is Inter Symbol Interference ISI Other factors like newlinethermal noise impulse noise and cross talk cause further distortions to the newlinereceived symbols newlineIn this thesis four different equalization techniques are introduced newlineto assure good reconstruction quality In digital communication the newlinetransmitted signals are generally in the form of multilevel rectangular pulses newlineThe absolute bandwidth of multilevel rectangular pulses is infinity If these newlinepulses pass through a band limited communication channel they will spread newlinein time and the pulse for each symbol may be smeared into adjacent time slot newlineand interfere with the adjacent symbol This is referred to as inter symbol newlineinterference ISI Hence an attempt has been made in the proposed newlinealgorithms to improve the performance of equalization system newline newline