Practical Considerationsof Wideband AQAM In deriving the upper bound performance of wideband AQAM portrayed in Figure 4.21(b), various assumptions were made and stated in Section 4.3.1. However, in order to provide a more accurate comparison between AQAM and constituent fixed modulation modes, those its assumptions must be justified and their effects have to be investigated. Specifically, perfect, i.e. error-free feedback was assumed for the DFE, while in practice erroneous decision can be fed b