Millimeter wave (mmWave) communications are recognized as a key technology in 5G architecture by achieving highly boosted data rate due to the large available bandwidth. For proper mmWave access design in practical systems, the impact of hardware impairments leading to performance degradations have to be considered adequately. In this extended abstract, we study several hardware aspects such as phase noise and non-linear power amplifiers using their models at mmWave frequency and evaluate the performance in an outdoor urban mmWave scenario. IQ imbalance, analog-to-digital converter and digital-to-analog converter resolution are discussed in the full paper. The respective influence on two air interfaces, namely, orthogonal frequency division multiplexing (OFDM) and single-carrier frequency domain equalization (SC-FDE), are analyzed and compared. It is shown that SC-FDE is much more robust against impairment from nonlinear power amplifiers than OFDM under system configuration at mmWave range. Although this less robustness is compensated by channel coding in OFDM systems significantly, SC-FDE with minimum mean square error equalization can still outperform OFDM in some coded cases.