All-optical Wavelength Division Research Articles

New design of all-optical multi-channel wavelength division multiplexer based on 2D PC waveguide structures with square rods

New design of all-optical multi-channel wavelength division multiplexer based on 2D PC waveguide structures with square rods

Quantum Dot Reflective Semiconductor Optical Amplifiers: Optical Pumping Compared with Electrical Pumping.

A comprehensive study has been conducted on quantum dot reflective semiconductor optical amplifiers (QD-RSOAs) with optical pumps (OPs). Moreover, few studies have been completed on OP-based QD-RSOAs. A comparison is made between them and QD-RSOAs with electrical pumps (EPs) in this study. It is shown that the dynamical properties of the device can significantly develop in the optical pumping version. The optical properties are studied for both methods. Moreover, by solving the coupled differential rate and signal propagation equations, the operation of the device in the pulse mode is investigated. Finally, it is proven that OP QD-RSOAs can perform significantly better in applications such as fast all-optical signal processing and wavelength division multiplexing in passive optical networks.

Temperature, stress, refractive index and humidity multi parameter highly integrated optical fiber sensor

Multi parameter measurement based on optical fiber sensor has been a research hotspot in recent years. In this work, four kinds of optical fiber sensors, LPFG, FBG, PMF and SMS are used. The transmission characteristics and sensing characteristics of each sensor are analyzed in detail. Based on the modulation of resonance wavelength by environmental variables, the accurate and synchronous real-time detection of temperature, stress, refractive index and humidity is realized. We use all-optical coupling cascade and wavelength division multiplexing (WDM) technology to prepare a highly integrated sensing device. The problem of signal crosstalk of each sensor is solved, and the cost of signal transmission and reception is greatly reduced. It is of great significance for monitoring a variety of environmental variables under extreme conditions.

Tunable all-optical AND logic gates via four-wave mixing based on graphene-on-silicon slot microring resonators

We propose a novel graphene-on-silicon organic hybrid slot microring resonator (GSHMIR) for tunable all-optical logic gates, which could offer broadband ultra-flattened dispersion with multiple zero-dispersion wavelengths (ZDWs) and high nonlinearity coefficient of 1.67 × 104 W−1m−1. Further investigations on temporal evolution dynamics for all-optical logic function suggest that the third-order dispersion will induce the temporal drift and tail oscillation of output pulses. The tunable all-optical AND logic function over the wavelength range from 1536 nm to 1569 nm could be obtained for 40 Gb/s signals with the conversion efficiency as high as −6.4 dB. These results are essential for all-optical wavelength division multiplexer (WDM) technology of future integrated optoelectronic systems, as well as providing a novel architecture for on-chip optical communications.

Photonic crystal add–drop filter: a review on principles and applications

Add–drop filter (ADF) is a key component in optical integrated circuits that can be used in all-optical communication networks and wavelength division multiplexing (WDM) systems. The quality factor, coupling efficiency, transmission efficiency and coupling length are important parameters in add–drop filters. Photonic crystal (PC) optical devices have become popular among researchers because their structure is suitable to embed into optical circuits. This paper covers a comprehensive review of the principle structure of ADF, coupled mode theory (CMT), types and recent applications in WDMs, accelerometer and bio/chemical sensors. Although there are some different categories of photonic crystal ring resonator-based ADF in general, all of them can be divided into photonic to two class of non-circular and circular. This article is reported a comprehensive study about ADF and improvement of these ADF.

All-optical wavelength division multiplexing amplifier based on vacuum induced nonreciprocal bistability in six-wave mixing process with a ring cavity

In this article, we experimentally investigate the nonreciprocal bistability (NB) of two six-wave mixing (SWM) processes inside of a ring cavity with a five-level rubidium atomic cell. The degree of NB can be analyzed by the nonreciprocal area (or non-overlapping area) including the frequency offset (in the x-direction) and the intensity difference (in the y-direction) between output states. The frequency offset between the two states of signals is resulting from the Kerr nonlinearity, while the cavity feedback dressing effect determines the intensity difference. Besides, the signals are amplified by the SWM polariton and vacuum induced enhancement. Based on the effect of NB, we study the realization of an all-optical wavelength division multiplexing amplifier (WDMA). The optical contrast and channel equalization radio of this WMDA is contributed from the degree of nonreciprocal area of output states of signals. Such results may have potential applications in all-optical devices and optical communication.

MMI-based all-optical four-channel wavelength division demultiplexer

In this paper, we present a four-channel wavelength division demultiplexer which is designed by means of cascading three $$1\times 2$$ multimode interference couplers. The proposed structure separates 980, 1310, 1490, and 1550 nm wavelengths into the appropriate ports. These wavelengths have been chosen for separation due to their importance in the optical communication systems. The performance of proposed demultiplexer has been optimized by choosing a suitable refractive index of the guiding region and geometrical parameters such as the width and length of coupler. Therefore, the total size of the demultiplexer is significantly reduced. Beam propagation method has been utilized in order to design and optimize the operation of the introduced structure. Simulation results indicate that the insertion losses of 980, 1310, 1490, and 1550 nm wavelengths are 0.52, 1.54, 0.64, and 1.4 dB, respectively.

Application Lambda Switching

Currently all-optical Dense Wavelength Division Multiplexing (DWDM) communication networks [1] are able to transport packet data end-to-end without the need to convert the transport wavelength(s) to an electrical signal. These networks today operate similar to their electrically-based network counterparts. That is, while all-optical DWDM networks have distinct advantages over electrically-based transport networks [2, 3], they have inherited much of their operational methodologies from previous electrically-based technologies. This paper discusses all-optical DWDM hardware technologies [4, 5] combined with newly developed algorithms [6] for network device addressing, and optical path construction; in a manner that creates an all-optical network topology called Application Lambda Switching. This new networking topology does not limit bandwidth, eliminates congestion, and Quality of Service (QoS) [7] issues. It can diagnose outages, faults, detect expansion, device failures, track inventory, and map itself all in real-time without the need for additional add-on technologies, or protocols typically used to perform these functions [8-10]. Application Lambda Switching (AλS) algorithms allow network access devices, not core-networking devices, to determine the bandwidth/speed of connections. AλS also utilizes an addressing algorithm that calculates device hardware addresses; therefore, the optical infrastructure itself can track its own topology and activity through the exchange and re-calculation of device addresses. Keywords: Addressing, device, DWDM, lambda, network, optical, switching, wavelength.

Nonlinear all-optical WDM based on spatial solitons in optical communication spectral regions

A new design of nonlinear all-optical wavelength division multiplexer (WDM) based on spatial solitons in optical communication spectral regions was proposed. By using the swing effect of spatial solitons in a Kerr-type nonlinear medium, the proposed nonlinear waveguide structure could function as an all-optical WDM. The numerical results show that the transmission efficiency is higher than 94%. The device separates spatial solitons interaction in a Kerr-type nonlinear medium and can be used in WDM networks with fixed-tuned receiver and tunable transmitter. It would be a potential key component in the applications of ultra-high-speed and ultra-high-capacity optical communications and optical data processing systems.

Survey on out-of-band failure localization in all-optical mesh networks

Out-of-band monitoring has been proposed as an effective approach for link failure localization in all-optical Wavelength Division Multiplexing (WDM) mesh networks. In this paper, the recent research related to out-of-band monitoring is overviewed. We define and formulate the related optimization problems under several design constraints, summarize the analytical results and discuss the related heuristic algorithms.

Dynamic Routing and Resource Assignment Algorithm In sloted optical Networks

All-optical wavelength division multiplexing networks are the most promising candidate for the next generation wideband backbone networks. To improve the utilization of wavelength, time division multiplexing technology is introduced. The routing, wavelength and time-slots assignment problem was studied in such time-space switched networks. Two new dynamic algorithms were proposed which distribute slots of the session request on multiple different wavelengths of single fiber separately based on fixed alternate routing and adaptive routing policy. Especially in LLR-MWLB algorithm, network link weights adjust adaptively with the available time slots of each link and load balancing strategy is adopted. The effectiveness of the proposed algorithms is demonstrated by simulations and results show the better performance. DOI: http://dx.doi.org/10.11591/telkomnika.v11i4.2336

Power distribution analysis for multiple modulation formats in an all-optical sampling wavelength division multiplexing system

An optimal power distribution analysis for an all-optical sampling orthagonal frequency division multiplexing (OFDM) scheme with multiple modulation formats including differential phase shift keyed (DPSK), differential quadrature phase shift keyed (DQPSK), and non-return-to-zero (NRZ) is proposed. The noise tolerances of different modulation formats are analyzed, and the optimal input power ratio between phase and intensity modulation formats for the best overall receiving performance is investigated under unchanged total input power. Moreover, this scheme can seamlessly coexist with the traditional WDM channel.

Network-Wide Local Unambiguous Failure Localization (NWL-UFL) via Monitoring Trails

Monitoring trail (m-trail) has been proposed as an effective approach for link failure localization in all-optical wavelength division multiplexing (WDM) mesh networks. Previous studies in failure localization rely on alarm dissemination via control plane signaling such that the network controller can collect the flooded alarms to form an alarm code for failure identification. Such cross-layer signaling effort obviously leads to additional control complexity. This paper investigates a novel m-trail failure localization scenario, called network-wide local unambiguous failure localization (NWL-UFL), where each node can perform UFL based on locally available on–off state of traversing m-trails, such that alarm dissemination in the control plane can be completely avoided. The paper first defines and formulates the m-trail allocation problem under NWL-UFL and conducts a series of bound analysis on the cover length required for localizing any single-link failure. This is the first study on monitoring trail allocation problem that aims to gain understanding on the consumed cover length via analytical approaches due to the special feature of the NWL-UFL scenario. A novel heuristic algorithm based on random spanning tree assignment (RSTA) and greedy link swapping (GLS) is developed for solving the formulated problem. Extensive simulation on thousands of randomly generated network topologies is conducted to verify the proposed scheme by comparing it to a naive counterpart and with the derived lower bounds. We also demonstrate the impact of topology diversity on the performance of the proposed scheme as well as its scalability regarding network sizes.

Enhancement of blocking performance in all-optical WDM networks via wavelength reassignment and route deviation

This paper deals with the problem of improving the performance of all-optical Wavelength Division Multiplexing (WDM) networks in terms of blocking probability. Blocking in such network architecture is caused mainly by the so-called wavelength continuity constraint (wcc), which requires a provisioned lightpath to occupy the same wavelength on all the links along its route. To alleviate the effect of wcc on the blocking performance, a rerouting strategy is proposed. The main idea behind this strategy lies in ensuring the creation of wavelength-continuous routes for the connections that are blocked due to wcc. Particularly, the proposed rerouting strategy is built upon two main pillars, namely wavelength reassignment and route deviation. The former strives to keep the physical route followed by the lightpath intact, while the latter changes the route of the lightpath when wavelength reassignment proves to be ineffective. The performance of the rerouting strategy is studied through extensive simulations in the context of networks employing the least congested path (LCP) routing algorithm and the first-fit (FF) wavelength assignment strategy. The reported results show that the proposed rerouting strategy can guarantee significant enhancement in terms of blocking probability while achieving near-optimal performance for networks utilizing a small number of wavelengths per fiber.

A heuristic algorithm for lightpath scheduling in next-generation WDM optical networks

We study the routing and wavelength assignment (RWA) problem of scheduled lightpath demands (SLDs) in all-optical wavelength division multiplexing networks with no wavelength conversion capability. We consider the deterministic lightpath scheduling problem in which the whole set of lightpath demands is completely known in advance. The objective is to maximize the number of established lightpaths for a given number of wavelengths. Since this problem has been shown to be NP complete, various heuristic algorithms have been developed to solve it suboptimally. In this paper, we propose a novel heuristic RWA algorithm for SLDs based on the bee colony optimization (BCO) metaheuristic. BCO is a newborn swarm intelligence metaheuristic approach recently proposed to solve complex combinatorial optimization problems. We compare the efficiency of the proposed algorithm with three simple greedy algorithms for the same problem. Numerical results obtained by numerous simulations performed on the widely used realistic European Optical Network topology indicate that the proposed algorithm produces better-quality solutions compared to those obtained by greedy algorithms. In addition, we compare the results of the BCO---RWA---SLD algorithm with four other heuristic/metaheuristic algorithms proposed in literature to solve the RWA problem in the case of permanent (static) traffic demands.

Dynamic circuit provisioning in all-optical WDM networks using lightpath switching

In this paper we investigate the problem of provisioning holding-time-aware (HTA) dynamic circuits in all-optical wavelength division multiplexed (WDM) networks. We employ a technique called lightpath switching (LPS) wherein the data transmission may begin on one lightpath and switch to a different lightpath at a later time. Lightpath switches are transparent to the user and are managed by the network. Allowing LPS creates a number of segments that can use independent lightpaths. We first compare the performance of traditional routing and wavelength (RWA) assignment to routing and wavelength assignment with LPS. We show that LPS can significantly reduce blocking compared to traditional RWA. We then address the problem of routing dynamic anycast HTA dynamic circuits. We propose two heuristics to solve the anycast RWA problem: anycast with continuous segment (ACS) and anycast with lightpath switching (ALPS). In ALPS we exercise LPS, and provision a connection request by searching for the best candidate destination node is such a way that the network resources are utilized efficiently. In ACS we do not allow a connection request to switch lightpaths. The lightpaths to each candidate destination node of a request are computed using traditional RWA algorithms. We first compare the performance of ACS to ALPS and observe that ALPS achieves better blocking than ACS. Furthermore, we also compare the performance of these two anycast RWA algorithms to the traditional unicast RWA algorithm. We show that the anycast RWA algorithms presented here significantly outperform the traditional unicast RWA algorithms.

Adjacent Link Failure Localization With Monitoring Trails in All-Optical Mesh Networks

Being reported as the most general monitoring structure for out-of-band failure localization approach, the monitoring trail (m-trail) framework has been witnessed with great efficiency and promises to serve in the future Internet backbone with all-optical mesh wavelength division multiplex (WDM) networks. Motivated by its potential and significance, this paper investigates failure localization in all-optical mesh networks using m-trails. By considering shared risk link groups (SRLGs) with up to all adjacent links of any node in the network, a novel algorithm of m-trail allocation for achieving unambiguous failure localization (UFL) of any single SRLG failure is developed. The proposed algorithm aims to minimize the number of required m-trails and can achieve superb performance with respect to the computation efficiency. We claim that among all the previously reported counterparts, this paper has considered one of the most applicable scenarios to the design of network backbone, and the proposed method can be easily extended to the case of node failure localization. Extensive simulation is conducted to verify the proposed algorithm in comparison to its existing counterparts.

On Provisioning in All-Optical Networks: An Impairment-Aware Approach

We investigate connection provisioning in an all-optical wavelength-division multiplexing (WDM) network in the presence of physical-layer impairments. As the channel bit rate increases, impairments pose a more serious problem, and lightpaths need to be routed intelligently, so that the destination node receives the signal with adequate quality. We study the models of major physical impairments that affect optical signals. With reasonable assumptions, we model the major impairments as link-based metrics and we formulate schemes for routing, which consider the impairment constraints imposed by the underlying physical infrastructure. Prior work in this area has focused on enumerating a set of paths based on criteria such as minimum hops/distances, and then selecting a path from this set based on complex calculations of signal quality. Our approach integrates verification of impairment constraints while searching for paths. Routing with multiple additive constraints being NP-hard, we give an optimal heuristic algorithm with fast execution time for practical networks, as well as a dynamic programming pseudo-polynomial-time algorithm for the case when one impairment constraint dominates. We also examine the case of a practical ¿all-optical¿ network with signal regeneration facility at some nodes. We explore routing in such a translucent network and discover that finding a simple feasible path passing through a regenerator is NP-complete.

Light-path establishment with PID control for effective wavelength utilization in all-optical wavelength-division multiplexing networks

We propose a dynamic light-path establishment method for using wavelengths effectively. In our proposed method, a proportional, integral, derivative (PID) controller is implemented in each edge node. The edge node determines the amount of data to be transmitted with PID control so that a constant amount of data can be stored in the buffer. In addition, light paths are established and released dynamically by comparing the output signal of the PID controller with the maximum amount of data that can be transmitted with the established light paths. Because data can be stored in the buffer for a short time, it is expected that the number of established light paths decreases. We evaluate the performance of the proposed method and investigate the impact of the setting parameters. The effectiveness of the proposed method is shown through a comparison with the conventional method.

QoS-Aware Wavelength Assignment With BER and Latency Constraints for All-Optical Networks

Physical impairments originating from optical fiber components and intermediate switching nodes can be the dominant reason calls are blocked in wide-area all-optical wavelength division multiplexing (WDM) networks. When a centralized network controller is used, estimating the impact of the physical impairments on the quality of a lightpath before provisioning it can cause a significant delay. In this paper, quality of service aware wavelength assignment algorithms are proposed that consider both bit-error rate (BER) and latency constraints. A novel wavelength assignment technique called wavelength ordering is shown via simulation to reduce the call blocking probability resulting from both physical impairments and excessive processing delay caused by channel BER estimation.