For the beyond 5G and future wireless communication systems, a variety of new-waveforms have been proposed to support emerging new use cases. The generalized frequency division multiplexing (GFDM) is attracting attention as one of the new-waveforms because the GFDM can flexibly change the number of subcarriers and symbols in both of frequency and time domains, while the out-of-band emission (OOBE) is almost same as that of the conventional CP-OFDM and the CP-DFTs-OFDM. Furthermore, many researches of the GFDM were evaluated with only AWGN or the condition of ideal channel estimation. To evaluate the practicality of the GFDM, effects of the channel estimation error should be considered. In this paper, we proposed a universal time-domain windowed GFDM (UTW-GFDM) that can improve OOBE significantly with low additional complexity and apply it to the LTE uplink system. The practicality of the proposed UTW-GFDM is shown by evaluating OOBE, PAPR, and BLER comprehensively under the 3GPP defined Extended Typical Urban (ETU) channel model. The proposed UTW-GFDM improves the OOBE reduction at channel-edge by 52.7 dB with a slight deterioration of less than 1.0 dB in PAPR and SNR to achieve BLER of 10 ^-3 compared to the conventional GFDM when QPSK is applied. Even in the case of 64QAM, the UTW-GFDM improves the OOBE reduction at channel-edge by up to 13.7 dB when 2.0 dB deterioration is acceptable for the SNR to achieve BLER = 10 ^-3 .