Abstract
To overcome the significant but unpredicted increase in the peak-to-average power ratio (PAPR) in the presence of an OFDM system, in this paper, a new implementation of an SLM scheme is represented. The effects of the candidate phase vectors on both the real and imaginary parts of the complex data symbols are discussed. Hence, instead of modifying the generated complex data symbol as a single component, the real and imaginary parts are modified independently using a corresponding phase element among a commonly generated phase vector. After applying an inverse fast Fourier transform (IFFT) for the real, imaginary, and original base-band vectors, the (most) minimum peak-to-average-power ratio (PAPR) for each part is observed. The phase vector that introduces the most minimal PAPR is considered to convert the original data block for transmission. This technique is called the optimal I/Q-SLM scheme. According to the results obtained, the CCDF PAPR performance of the proposal acquires greater decibel reduction than a conventional SLM (conv.-SLM) method at different subcarrier length N and candidate phase vectors U. In addition, at different levels of input-back-off (IBO), the power spectral density (PSD) of the original and modified OFDM signals are represented, where the PSD of the proposal shows the best out-of-band characteristic against conv.-SLM.