1. An apparatus comprising: a receiver configured to process a signal received over a non-linear wireless channel, wherein the received signal reflects a source signal comprising a plurality of source symbols, and includes linear and non-linear interference effects induced based on a faster-than-Nyquist (FTN) signaling rate applied to the source signal and high-power amplification and filtering for transmission over the non-linear wireless channel; wherein the receiver is configured to estimate the plurality of source symbols of the received signal based on a plurality of outer-loop decoding iterations, wherein a current outer-loop decoding iteration is employed to at least determine an improved estimate of one or more of the plurality of source symbols based on a set of soft information of the current outer-loop decoding iteration, and the improved estimate of the one or more of the plurality of source symbols is fed to a next outer-loop decoding iteration to further improve the estimate of the one or more of the plurality of source symbols, and wherein the receiver comprises: a likelihood metric processor configured to generate the set of soft information of the current outer-loop decoding iteration based on a current estimate of one or more of the source symbols and a final set of soft information from a previous outer-loop decoding iteration; wherein the current estimate of the one or more source symbols is based on a previous estimate of the linear and non-linear interference effects exhibited by the received signal, which is based on the final set of soft information from the previous outer-loop decoding iteration.