Link Adaptation refers to transmission schemes in which the transmitter adapts its mode (Constellation size, rate, code, power etc...) based on channel conditions. High rate transmission could take place when the channel is favorable and during deep fades robust schemes are enabled. This invariably requires channel state information (CSI) at the transmitter side. We studied the performance of adaptive modulation schemes in personal communication systems under various fading conditions and practical system constraints. We also Analyzed the performance of Adaptive modulation over wideband frequency selective channels with predicted Channel State estimates for systems using equalization and systems using Orthogonal frequency division Multiplexing OFDM)