In this paper, we present a dynamic energy efficient routing and spectrum assignment algorithm with regenerator placement (RP) capability for elastic optical networks. algorithm, virtual graph is considered given network topology graph, whereby the cost functions of computed according to consumption corresponding links intermediates routers. Furthermore, arrived connection request served by finding most energy-efficient path among possible candidate paths. Then, quality transmission (QoT)...

Visible light communication (VLC) has emerged as a viable supplement to existing radio frequency (RF) systems. The limited modulation bandwidth of sources is one the significant challenges in multiuser (MU) VLC systems, which prohibits transmission at high data rates for each user. Since an array LEDs used illuminate room, MU system utilizing massive multiple-input multiple-output (mMIMO) orthogonal frequency-division multiplexing (OFDM) proposed achieving this paper. distances multiple...

We theoretically and experimentally evaluate a beat interference cancellation receiver (BICR) for direct detection optical orthogonal frequency-division multiplexing (DD-OFDM) systems that improves the spectral efficiency (SE) by reducing guard band between carrier OFDM signal while mitigating impact of signal-signal mixing (SSMI). Experimental results show bit-error-rate (BER) is improved about three orders magnitude compared to conventional after 320 km single-mode fiber (SMF) transmission...

A novel architecture for efficient time and frequency synchronization, applied to the long-term evolution (LTE) standard, is proposed. For symbol timing, we propose applying a symbol-folding method on top of sign-bit reduction technique, leading algorithm cyclic prefix-type recognition in LTE. Following fractional carrier offset estimated compensated using an adaptive gain loop, which allows high-accuracy compensation short interval. In domain, cell search, technique matched filter primary...

For multiple-input-multiple-output underwater wireless optical communication (UWOC) systems with on-off keying modulation, we obtain the optimal power allocation policies that minimize bit error rate (BER), subject to average constraints. In this article, consider a comprehensive channel model takes into account absorption, scattering, and weak turbulence-indeed lognormal fading. The are obtained using perfect state information available at receiver (CSIR) transmitter (CSIT) for both MISO...

In this paper, we study the problem of maximizing sum throughput <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${K}$ </tex-math></inline-formula> users in a hybrid heterogeneous visible light communication (VLC)/radio frequency (RF) wireless system. This is done by optimizing transmission time intervals division multiple access (TDMA) scheme allocated to two different downlink (DL) scenarios. both...

The use of low-resolution data converters in the radio-frequency (RF) chains all-digital massive multiple-input multiple-output (MIMO) basestations promises significant reductions power consumption, hardware costs, and interconnect bandwidth. We propose a quantization-aware data-detection algorithm which mitigates performance loss 1-bit quantized MIMO orthogonal frequency-division multiplexing (OFDM) systems. Since system heavily depends on quality channel estimates, we also develop...

Achieving reliable communication over different wavelength channels and modes is one of the main goals Mode Division Multiplexing-Wavelength Multiplexing (MDM-WDM) transmission. The reliability can be described by minimum Signal to Noise Ratio (SNR) margin which depends on launch power, gain Few-Mode Erbium-Doped Fiber Amplifiers (FM-EDFA), nonlinear impairments (FMF). In this paper, we develop Enhanced Gaussian (EGN) model for FMF, used in both weak strong coupling regimes. We validate...

Mode-division multiplexing (MDM) using few-mode fibre (FMF) has received increasing attention to address the exponential growth of data traffic in long-haul optical communication systems. Also, combining MDM with wavelength-division (WDM) is a promising approach for dramatically growing transmission capacity such However, major barrier this regard FMF nonlinear effects, which can significantly reduce link performance. In paper, order alleviate we focus on power allocation links by optimizing...

In this paper, we analyze and obtain performance of a multilevel Optical Code Division Multiple Access (OCDMA) system with Variable-Weight Orthogonal Codes (VW-OOCs) under the same-bit-energy assumption. The exact error-probability is derived for Generalized VW-OOCs (codes arbitrary cross-correlation) which necessary optimum design OCDMA systems. We show that bit power has an important role on determining codes different weights. Furthermore, results reveal low-weight depends weight...

Quality of transmission (QoT) estimation tools for fiber links are the enabler deployment reconfigurable optical networks. To dynamically set up lightpaths based on traffic request, a centralized controller must base decisions reliable performance predictions. QoT methods can be categorised in three classes: exact analytical models which provide accurate results with heavy computations, approximate formulas that require less computations but deliver reduced accuracy, and machine learning...

Visible light communications (VLC) is a promising solution as an alternative for the fully occupied radio frequency bands in near future. The rear (tail) and front of vehicles have lamps that can be used vehicular visible (VVLC) systems. However, one main challenges VLC systems line-of-sight (LoS) blockage issue. In this paper, we propose installation intelligent reflecting surfaces (IRSs) (i.e., smart mirrors) on back to overcome issue VVLC We assume three different patterns angular...

We propose and demonstrate a novel architecture for four-wave mixing (FWM)-based recognition of spectral amplitude code (SAC) labels in optical packet-switched networks. With proper design, unique FWM idler each SAC label, referred to as label identifier (LI), is generated nonlinear medium. A serial array fiber Bragg gratings then used reflect the LI wavelengths. Each associated with amount delay between two signals received at photodiodes (PDs). Label achieved by measuring this time...

In this article we present an all passive optical iterative interference cancellation method for CDMA. We propose the receiver structure based on advanced binary logic gates (ABOLGs). Since performance bottleneck in communication systems is conversion from to electronic domains detectors, has been performed domain. incoherent systems, have only positive values signals. proposed system, bypass negative using arrays. simulations consider multiple access and neglect other sources of noise....

Recently, Enhanced Gaussian Noise (EGN) model of few-mode fiber nonlin-earity has been proposed improving GN accuracy. However, EGN is considerably complex. We propose a closed-form and provide substantial simulations indi-eating its

A novel machine learning (ML) clustering algorithm, named light-fidelity (LiFi) Grid, is proposed to design amorphous cells of LiFi access points (APs) in order maximize the minimum signal-to-interference-plus-noise ratio (SINR) from viewpoint user-centric (UC) network design. The algorithm consists two phases. Explicitly, first phase finding clusters user densities based on mean-shift (MS) algorithm. In contrast some other algorithms, such as K-means, MS does not need know number advance....

In free space optical (FSO) communication system, the maximum likelihood (ML) is optimum detector considering perfect channel state information (CSI) at receiver. However, ML does not provide a proper performance in imperfect CSI scenario. Therefore, deep learning based detection method proposed this paper. paper, we use neural network to get mapping function of received signal and transmitted symbol streams. Moreover, end-to-end approach using with conventional compared for both scenarios....

Optical performance monitoring (OPM) is crucial for facilitating the management of future few-mode fiber (FMF)-based transmissions. OPM deploys fault detection and link diagnosis by measuring physical layer states provides feedback to controller. Recently, machine learning (ML) has gained a lot attention OPM, various ML algorithms were developed, wherein selection proper method challenge. Ensemble (EL) solves this challenge combining different models; however, simultaneous employment suffers...

For a serial relaying underwater wireless optical communication (UWOC) system with ON-OFF keying modulation, we theoretically evaluate the optimal power allocation techniques in order to minimise end-to-end bit error rate (BER), subject transmission constraints. At first, BER respect all degrading effects of UWOC channel, namely scattering, absorption, and turbulence-induced fading then develop closed-form expression as function transceiver parameters water type. The methods are obtained...