Wireless communications became an integrated part of the human life. Fifth generation (5G) is modern communication which provides enhanced mobile broadband (eMBB), ultra reliable low latency (URLLC), and massive machine type (mMTC). Thus, 5G have to provide coverage multi-numerology devices, therefore, modulation access schemes are suggested in literature such as cyclic prefix orthogonal freque...

The nonlinear distortion introduced by the dead time strongly limits throughput of highly sensitive SPAD-based optical wireless communication (OWC) systems. Optical OFDM can be employed in systems with SPAD arrays to improve spectral efficiency. In this work, a theoretical performance analysis OWC system asymmetrically-clipped (ACO-OFDM) is presented. impact nonlinearity on investigated. additi...

A novel group of interleaved orthogonal frequency division multiplexing (IL-OFDM) and partial transmission IL-OFDM (PT-IL-OFDM) schemes are proposed for optical coherent detection. In the interleaved operation, the odd (or even) subcarriers of an OFDM symbol are reserved (closed). Such an interleaved arrangement can gain the tolerance toward phase noise induced interchannel interference (PN-ICI...

Optical Orthogonal Frequency-Division Multiplexing (O-OFDM) is eminently suitable for mitigating the multi-path and chromatic dispersion in both Visible Light Communications (VLC) Fiber Communications. We commence our discourse by surveying conception historic evolution of O-OFDM designed VLC optical fiber, culminating birth its most flexible design alternative, namely Layered Asymmetrically Cl...

Fifth generation (5G) wireless technology is a new communication system that must meet different complementary needs: the high data rate for mobile services, low energy consumption and long-range connected objects, latency to ensure real-time critical applications and, spectral efficiency improve overall capacity. The waveforms associated signal processing present real challenge in implementati...

OFDM combined with TDM (OFDM/TDM) can be used to reduce a high peak-to-average power ratio (PAPR) of OFDM, but the PAPR reduction is not sufficient. To further reduce the PAPR, an amplitude clipping can be applied. In this letter, we investigate the effect of clipping on OFDM/TDM with and without channel coding. It is shown that amplitude clipped OFDM/TDM has an advantage over clipped OFDM with...

<p>In recent years, the wireless spectrum has become increasingly scarce as demand for services grown, requiring imaginative approaches to increase capacity within a limited spectral resource. This article proposes new method that combines modified symbol time compression with orthogonal frequency division multiplexing (MSTC-OFDM), enhance narrow-band internet of things (NB-IoT) system. T...

Carrier Interferometry (CI) approaches, including Carrier-Interferometry Orthogonal Frequency Division Multiplexing (CI/OFDM) and Pseudo-Orthogonal Carrier-Interferometry OFDM (PO-CI/OFDM), have been proposed to enhance OFDM’s performance and reduce OFDM’s peak-to-average power ratio (PAPR). However, the existing high-throughput, high-performance PO-CI/OFDM system is limited for real signaling....

A carrier separated OFDM system is proposed to support high data rates in mobile multiple access environments. OFDM is considered to support high data rates and carrier separation is introduced to combat multipath fading. The performance is comparable to that of a frequency hopped OFDM system. While promising robustness against multipath fading, the computational complexity of a carrier separat...

This paper presents a new channel estimation/equalization algorithm for coherent OFDM (CO-OFDM) digital receivers, which enables the elimination of the cyclic prefix (CP) for OFDM transmission. We term this new system as the zero-guard-interval (ZGI)-CO-OFDM. ZGI-CO-OFDM employs an overlapped frequency-domain equalizer (OFDE) to compensate both chromatic dispersion (CD) and polarization mode di...