OFDM is an essential part of the physical layer structure in 4G communication systems. Despite having many advantages compared to other modulation types, OFDM has the significant drawback of causing high out-of-band emissions (OOBE). This resulted in the consideration of alternative modulation schemes for the future communication standards. In this work, two of those alternatives, namely GFDM and WCP-COQAM are compared with OFDM under the efTects of digital-to- analog converter (DAC) and power-amplifier (PA) non-Iinearity taking into account the spectral mask requirements in the LTE standard. The performance metrics used in the comparisons are the error-vector magnitude (EVM), signal-to-intereference ratio (SIR) and average powers of the transmitted signals using the 3 modulation schemes. The results turned out to be such that there is no significant difference between the 3 modulation types in terms of the performance metrics taken into consideration.