An examination is made of fiber-optic code-division multiple-access (FO-CDMA), a technique in which low information data rates are mapped into very-high-rate address codes (signature sequences) for the purpose achieving random, asynchronous communications free network control, among many users. The need special class signature sequences to achieve capability using signal processing techniques discussed. A called optical orthogonal (OOCs) that provide auto- and cross-correlation properties...

An optical orthogonal code (OOC) is a family of

For pt.I see ibid., vol.37, no.8, p.824-33 (1989). In Part I a technique based on optical orthogonal codes was presented to establish fiber-optic code-division multiple-access (FO-CDMA) communications system. The results are used derive the bit error rate of proposed FO-CDMA system as function data rate, code length, weight, number users, and receiver threshold. performance characteristics for variety parameters discussed. A means reducing effective interference signal by placing an...

A new technique for encoding and decoding of coherent ultrashort light pulses is analyzed. In particular, the temporal statistical behavior pseudonoise bursts generated by spectral phase coding optical discussed. analysis motivated recent experiments that demonstrate high-resolution picosecond femtosecond suggest possibility ultrahigh speed code-division multiple-access (CDMA) communications using this technique. The evolution into low intensity as a function degree traced. results are...

In this paper, we analytically study the performance of multiple-input multiple-output underwater wireless optical communication (UWOC) systems with ON-OFF keying modulation. To mitigate turbulence-induced fading, which is amongst major degrading effects channels on propagating signal, use spatial diversity over UWOC links. Furthermore, absorption and scattering are considered in our analysis. We obtain exact an upper bound bit error rate (BER) expressions for both optimal equal gain...

Optical signal propagation through underwater channels is affected by three main degrading phenomena, namely, absorption, scattering, and fading. In this paper, we experimentally study the statistical distribution of intensity fluctuations in wireless optical with random temperature salinity variations, as well presence air bubbles. particular, define different scenarios to produce on water refractive index across path and, then, examine accuracy various distributions terms their goodness...

We demonstrate the spreading of femtosecond optical pulses into picosecond-duration pseudonoise bursts. Spreading is accomplished by encoding pseudorandom binary phase codes onto frequency spectrum. Subsequent decoding spectral phases restores original pulse. propose that frequency-domain and coherent ultrashort could form basis for a rapidly reconfigurable, code-division multiple-access telecommunications network.

The authors provide an analysis of the performance optical orthogonal codes in code division multiple access (CDMA) network by considering probability distribution interference patterns. It is shown that actual close to a previous estimate. A less structured temporal which words are allowed overlap at two pulse positions also considered. bit error for this class obtained cases: with and without hard-limiting receivers. may increase number users considerably significant loss performance.<...

In this paper, we characterize the performance of relay-assisted underwater wireless optical code division multiple access (OCDMA) networks over turbulent channels. addition to scattering and absorption effects channels, also consider turbulence as a log-normal fading coefficient in our analysis. To simultaneously asynchronously share medium among many users, assign unique orthogonal (OOC) each user order actualize OCDMA-based network. The most significant challenge communication is ability...

In this paper, we present a quality-of-transmission (QoT) aware dynamic routing, modulation level, and spectrum assignment scheme referred to as QoT-aware RSA. The proposed RSA has three stages: path computation with level assignment, selection, assignment. Two schemes are presented in the stage namely, modified Dijkstra K-shortest-path algorithms. A closed-form expression is derived model fiber nonlinearity effects impairments of intermediate routers. This utilized estimate network...

In this letter, we analytically evaluate the end-to-end bit error rate (BER) of point-to-point multi-hop underwater wireless optical communication (UWOC) systems with respect to all degrading effects UWOC channel, namely absorption, scattering, and turbulence-induced fading. To do so, first derive BER expression a single-hop link as building block for evaluation. We also apply Gauss-Hermite quadrature formula obtain closed-form solution system in case lognormal fading channel. Numerical...

In this Letter, we realize the concept of analog computing using an engineered gradient dielectric meta-reflect-array. The proposed configuration consists individual subwavelength silicon nanobricks, in combination with a fused silica spacer and silver ground plane, realizing reflection beam full phase coverage 2π degrees, as well amplitude range 0 to 1. Spectrally overlapping electric magnetic dipole resonances, such high-index metasurfaces can locally independently manipulate incident...

In this paper, we introduce and investigate a cellular underwater wireless optical code division multiple-access (OCDMA) network based on orthogonal codes (OOC). The structures, principles, performance of the OCDMA in various water types are presented. Since links considered for high-bandwidth communications at short ranges, will place set base transceiver stations (OBTS) each center hexagonal cell to cover larger area. OBTSs connected via fiber optic an controller (ONC) which operates as...

This paper presents a comprehensive study of underwater visible light communications (UVLC), from channel characterization, performance analysis, and effective transmission reception methods. To this end, we first simulate the fading-free impulse response (FFIR) UVLC channels using Monte Carlo numerical procedure to take into account absorption scattering effects; then characterize turbulence effects, multiply aforementioned FFIR by fading coefficient modeled as lognormal random variable...

In this paper, we experimentally investigate the statistical distribution of intensity fluctuations for underwater wireless optical channels under different channel conditions, namely fresh and salty with without air bubbles. To do so, first measure received signal a large number samples. Based on normalized acquired data coherence time probability density function (PDF) are obtained scenarios. Our experimental results show that salt attenuates while bubbles mainly introduce severe...

Leveraging subwavelength resonant nanostructures, plasmonic metasurfaces have recently attracted much attention as a breakthrough concept for engineering optical waves both spatially and spectrally. However, inherent ohmic losses concomitant with low coupling efficiencies pose fundamental impediments over their practical applications. Not only can all-dielectric tackle such substantial drawbacks, but also CMOS-compatible configurations support Mie resonances that are invariant to the...

To cope with the unprecedented growth of mobile data traffic, we investigate performance gains obtained from unifying coverage-centric 4G networks and capacity-centric fiber-wireless (FiWi) broadband access based on data-centric Ethernet technologies resulting fiber backhaul sharing WiFi offloading capabilities. Despite recent progress backhaul-aware studies capacity-limited links, performance-limiting impact latency reliability has not been examined in sufficient detail previously. In this...

Underwater wireless optical communications are an emerging solution to the expanding demand for broadband links in oceans and seas. In this paper, a cellular underwater code division multiple-access network is proposed provide commercial military applications. The orthogonal codes employed as signature of mobile users. Fundamental key aspects network, such its backhaul architecture, potential applications, design challenges, presented. particular, promising localization positioning scheme...

An ultra-wide bandwidth time-hopping spread-spectrum code division multiple-access system employing a binary PPM signaling has been introduced by Scholtz (1993), and its performance was obtained based on Gaussian distribution assumption for the interference. In this paper, we begin first proposing to use practical low-rate error correcting in without any further required expansion. We then present more precise analysis of both coded uncoded schemes. Our shows that is not accurate predicting...

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)...

In this paper, the problem of routing, modulation level, core, and spectrum assignment (RMCSA) in space-division-multiplexed elastic optical networks (SDM-EONs) is studied. We formulate as a mixed-integer linear programming (MILP), which dedicated shared path protection schemes are supported SDM-EONs with multi-core fibers (MCFs) inter-core crosstalk MCFs strictly modeled. Furthermore, an efficient heuristic algorithm proposed to solve RMCSA large scale scenario. Numerical results reveal...

We study the performance of optical code-division multiple access (CDMA) systems using various receivers structures. Two general classes based on required electronic bandwidth are studied. Optical orthogonal codes (OOCs) utilized as signature sequences and studied in this paper takes into account effect all major noise sources, i.e., quantum shot-noise, dark current noise, Gaussian circuit noise. Furthermore, introduces a generalized method analyzing CDMA receiver Required mean number photon...

All-optical systems, which perform signal processing functions optically so that the conversion from optical to electrical is done only when desired, are considered. Three such schemes discussed, namely, fiber-optic code-division multiple-access (CDMA) neuromorphic CDMA and ultrashort-light-pulse systems. Fiber-optic systems in incoherent techniques used establish first examined. In particular, a novel class of sequences for called orthogonal codes, discussed. The codes then applied various...

In this paper, we present a deep insight into the behavior of optical code-division multiple-access (CDMA) systems based on an incoherent, intensity encoding/decoding technique using well-known class codes, namely, orthogonal codes (OOCs). As opposed to parts I and II where OOCs with cross-correlation <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$lambda = 1$</tex> were considered, consider generalized...

In this paper we analyze and investigate the bit error rate (BER) performance of multiple-input multiple-output underwater wireless optical communication (MIMO-UWOC) systems. addition to exact BER expressions, also obtain an upper bound on system BER. To effectively estimate use Gauss-Hermite quadrature formula as well approximation sum log-normal random variables. We confirm accuracy our analytical expressions by evaluating through photon-counting approach. Our simulation results show that...