New errorprediction techniques forturbo-coded OFDM systems andimpact on adaptivemodulation and coding

Thispaperdeals withPacket Error Rate(PER)prediction andits impact onAdaptive Modulation andCoding (AMC)for anOFDM turbo codedtransmission onamultipath channel. Wecompare four LinkQuality Metrics (LQM),including the Signal toNoiseRatio (SNR), thecapacity, andtwoLQM whichwedesigned toexploit thesoft outputs oftheturbodecoder. Since error prediction isusedtoperform AMC, weassess thethroughput performance ofarealistic system employing eachofthefour LQM.Thecomparison showsthat while SNRperforms poorly andcapacity remains suboptimum, thetwometrics exploiting soft outputs approach thethroughputwhichwouldbeachieved byperfect PERprediction.