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Results for “Optical Wireless Communications (OWC)”

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Autoencoder-Based Optical Wireless Communications Systems

In this study, we propose deep neural network autoencoders for capturing the end-to-end performance of the single- and multi-user optical wireless communications (OWC) systems. We compare the end-toend performance of the proposed autoencoders (learningbased OWC systems) with the state-of-the art model-based OWC systems in terms of the block error rate (BLER) metric. Our numerical results indicate that the proposed learning-based OWC system outperforms the model-based counterparts in both single- and multi-user settings.

99 GENERAL AND MISCELLANEOUS↗

Low-PAPR interleaved single-carrier FDM scheme for optical wireless communications

As a potential complementary access technology for the 5G wireless systems, optical wireless communication (OWC) gains extensive attention for decades owing to its numerous advantages of broad license-free spectrum, immunity to electromagnetic interference and high-level privacy. However, two rigorous obstacles to achieve high data-rate OWC transmission are the severe nonlinear clipping of transmitter and high-frequency attenuation of OWC system. In this paper, we propose the first interleaved single-carrier frequency-division multiplexing (I-SC-FDM) scheme for OWC systems. Compared with orthogonal frequency-division multiplexing (OFDM), I-SC-FDM has a lower peak-to-average power ratio, which makes it more immune to the nonlinearity clipping in OWC systems. Meanwhile, for the bandwidth-limited OWC systems, I-SC-FDM has better performance on resistance to the serious high-frequency distortion. The simulation results indicate that, under the transmitter nonlinearity and optical-wireless diffuse fading channel, the maximum Q{sup 2} of I-SC-FDM is about 3.44 dB and 3.14 dB higher than that of OFDM when 4-ary quadrature amplitude modulation (4-QAM) and 16-QAM are modulated, respectively. The results show the feasibility and advantages of I-SC-FDM for cost-sensitive OWC systems.

77 NANOSCIENCE AND NANOTECHNOLOGY↗

A cost-effective 100 Gbps SAC-OCDMA–PDM based inter-satellite communication link

Satellite communication is one of the pioneer technologies to provide seamless communication across the globe. With large number of satellites deployed in the space, inter-satellite communication has become an important phenomenon for researchers to establish communication link between satellites. In this work, a cost-effective inter-satellite communication system is proposed by using spectral amplitude coding based on optical code division multiplex access technique and polarization division multiplexing scheme. Ten channels, each carrying 10 Gbps non-return to zero encoded data, are transmitted over 25,000 km inter-satellite optical wireless communication (Is-OWC) link. Furthermore, Is-OWC is subjected to space turbulences such as transmitting and pointing errors. The reported results show the successful transmission of 100 Gbps data over Is-OWC link.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗