efficient frequency-domain equalization at the receiver. The DFT-spread-OFDM generated in frequency domain, similar to OFDM as illustrated in Fig. 3.14, where the signal mon processing blocks in OFDM and DFT-S-OFDM are distinguished from those that com- are downlink specific to DFT-S-OFDM. This allows for a relatively high degree of commonality with the OFDM baseband processing using the same parameters, for example, clock fre- quency, subcarrier spacing, FFT/IFFT size. The use of DFT-S-OFDM in the LTE uplink Channel Processing block specific to DFT-S-OFDM Figure 3.14 Transmitter structure for DFT-S-OFDM with localized subcarrier mapping schemes (note that NDFT < NFFT) [47]. New Radio Access Physical Layer Aspects (Part 1) 331 was mainly due to relatively inferior PAPR properties of OFDM that resulted in worse uplink coverage compared to DFT-S-OFDM. The PAPR characteristics are important for cost-effective design of UE's PAs. The principles of DFT-S-OFDM signal processing can be explained as follows. The ith transmitted symbol in a DFT-S-OFDM system without CP in single transmit/receive antenna case can be expressed as a vector of length NFFT samples defined by = FODx where X = XM) T is an NDFT 1 vector with NDFT QAM-modulated symbols (the superscript "T" denotes matrix transpose operation), D is an NDFT X NDFT matrix which per- forms NDFT-point DFT operation, O is the NFFT X NDFT mapping matrix for subcarrier assignment, and F performs NFFT-point IFFT operation. After the propagation through the multipath fading channel and addition of the AWGN and removing the CP and going through the NFFT-point FFT module, the received signal vector in the frequency domain can be expressed as =F-1-HFODx + W where H is the diagonal matrix of channel response and W is the noise vector. Note that the maximum excess delay of the channel is assumed to be shorter than the CP; therefore, the ISI can be mitigated by the CP. The amplitude and phase distortion in the received signal due to the multipath channel is compensated by a frequ