EXITCHARTAIDEDIRREGULARCONVOLUTIONALCODE DESIGNFORITERATIVE DOWNLINK SDMA SYSTEMSUSINGIMPERFECTCHANNEL STATEINFORMATION
Chun‐Yi Wei · 2007
Transmission (MUT)technique. Thephilosophy ofthis MUT isthat inthepresence ofperfect knowledge oftheindividual Weanalyze aprecoded anditeratively detected downhink mul- usr'Sai-eprlCane mus epne(TCR tiuser system employing imperfect Spatio-Temporal Channeltber encouTered,rt Chempls tesunie uSeImpulse Response attheTransmitters (ST-GIRT) withtheaid tobeencountereds theMUT scheme exploits theunsquer userofExtrinsic Information Transfer (EXIT) charts. A Precodedmitte Signls. Gientatte M d e ssetially ueliminae Iterative DownLink Space Division Multiple Access (PI-DL-.te M igthet st-M intimu MeanSare SDMA sytemproosed inourpreiou resarc isfurher theMUI,thelow-complexity soft-out MinimumMeanSquare SDMA)system proposed inourprevious research isfurtherError (M0MSE) detector of[4]mnay beinvoked bythePI-DLimproved andshowntobecapable ofmaintaining aninfinites- SDMA multiuser system.Eurthermore, aunity-rate conimally lLow BER,despite using imperfect ST-CIRT. A furtherSD Amlisryte. Fthmo,auny-tecimally lowBER,tdese uIDLSing imerecisthSt- Aefusin h volutional encoder using asingle shift register stage [5]is novel feature oftheVPI-DL-SDMA system isthat wedesignl an emloe foprcdn,bcuei a eosrtdi 2 IrRegular Convolutional Code(IRCC) withtheaidofEXIT thtteerfor o aecoding issubstatil imchart analysis forcreating anopenEXITtunnel between the prvdwhen carfrie outeby dexch ing extrinsi inforatio n innedeode's adoterdecder' EXT crve taredced proved, whencarried outbyexchanging extrinsic information EbINn dalueoder and ouere cutesmaty awBERecbetween theunity-rate precoder's decoder andthechannel deLb/Novalue andhence maintain aninfinitesimally lowBER. coder.