OCDM System with PAPR Reduction for Sub-THz Wireless Communication

Next-generation wireless technology which will use Sub-THz frequency band will support several new services and applications. However, there is a very high propagation loss of communication signals in Sub-THz frequency band. Furthermore, the power efficiency will be greatly decreased because of the high peak-to-average power ratio (PAPR) in the multi-carrier communication signal. As a result, PAPR reduction is the most important in 6G wireless communication system than 4G long-term evolution (LTE), 5G new radio (NR) schemes because it will use the Sub-THz frequency band of very high propagation loss. Therefore, spread spectrum technology termed as orthogonal chirp division multiplexing (OCDM) takes into account for the orthogonality of cyclically shifted quadratic chirp signals in order to increase the spectral efficiency and reduce the propagation loss. In this paper, we suggest a new discrete Fourier transform (DFT)-Spread OCDM (DFT-Spread OCDM) system for designing waveform and suitably acceptable PAPR reduction. Comparing the proposed scheme to the conventional OFDM and OCDM systems, simulation findings show that this technique greatly reduces PAPR by about 2 dB. Additionally, we examine the bit error ratio (BER) performance in AWGN channel. This DFT-Spread OCDM scheme performs almost similar results as compared to the previous OFDM and OCDM systems.