Upperboundsarederivedontheprobabilityoferrorthatcanbeachievedbyusingblockcodesongeneraltime-discretememorylesschannels.Bothamplitude-discreteandamplitude-continuouschannelsaretreated,bothwithandwithoutinputconstraints.Themajoradvantagesofthepresentapproacharethesimplicityofthederivation