There are two types of signal waveform: single-carrier (SC) and multi-carrier (MC). A representative of MC signal is orthogonal frequency division multiplexing (OFDM). SC signal can be considered as a linear precoded OFDM signal and has lower peak-to-average power ratio (PAPR) than OFDM signal. There exist many variants between SC and MC signals depending on the linear precoder. The linear precoder can be designed to generate a SC signal having very-low-PAPRbased on the minimum variance of instantaneous transmit power (VIP) criterion, or can be extended to generate SC spread spectrum (SS) signal. The frequency-domain based precoder design is presented and a tradeoff between PAPR and bit-error rate (BER) is discussed in this paper.