Impact Of Inter-core Crosstalk Research Articles

Auxiliary graph-based energy-efficient routing resource allocation algorithm in space division multiplexing elastic optical networks

Space division multiplexing elastic optical networks (SDM-EONs) are considered as a efficient solution for increasing the link’s capacity. However, the SDM-EONs brought challenges to be explored, notably the routing, core and spectrum assignment (RCSA) problem. For the real network, another important issue should be considered is the problem of energy consumption. The auxiliary graph (AG) can abstract node devices into elements in it and support various routing policies for different purposes by adjusting the weights of AG edges. Therefore, this paper proposes an auxiliary graph-based energy efficient routing resource allocation algorithm (AG-EERRA) to jointly optimize the energy consumption and RCSA. Each node of the auxiliary graph is abstracted from the devices of physical node. The intra edge weights of nodes set the function associated with the energy consumption model. The inter edge weights of node are composed link length, free frequency slots, modulation efficiency and the value of core crosstalk innovatively. Meanwhile, the impact of inter-core crosstalk on request is reduced by crosstalk avoidance strategy and crosstalk aware strategy. In the proposed auxiliary graph, the shortest weight path is selected to transmit requests that can reduce network energy consumption and blocking probability. Under the high-load network, request splitting is performed for the requests that cannot successfully find a route to improve energy efficiency. Simulation results show that the proposed algorithm can improve the network energy efficiency while reducing request blocking probability compared to comparison algorithms.

Routing Core and Spectrum Allocation Algorithm for Inter-Core Crosstalk and Energy Efficiency in Space Division Multiplexing Elastic Optical Networks

Elastic optical networks (EONs) and space-division multiplexing (SDM) have emerged as a promising technology to accommodate the high-capacity and dynamic bandwidth demands of next-generation network. However, the problems of high energy consumption and inter-core crosstalk (ICXT) in space-division multiplexing elastic optical networks (SDM-EONs) are also particularly prominent. In this paper, we proposed an energy efficient grooming and hybrid crosstalk solution (EEG-HCS) algorithm. Firstly, in the routing strategy, a candidate path sorting formula combined the path length and path load state is designed to select the candidate paths and balance the network load. According to the sorting result, whether the current candidate path satisfied the energy efficiency grooming condition or not is determined. When the candidate path meet the energy efficiency grooming condition, the energy efficiency grooming algorithm is used to reduce the transmission energy consumption. For traffic request that do not satisfied the grooming condition, a new optical path is established. Through the core priority grouping, combined with crosstalk avoidance strategy and ICXT aware algorithm, the impact of inter-core crosstalk is minimized, and the probability of successful transmission is improved. In order to evaluate the performance of proposed algorithm, ICXT improvement index is defined. The simulation results show that the proposed algorithm can significantly reduce the energy consumption of space-division multiplexing elastic optical network system while ensuring the optimal blocking probability performance.

10 Gbps CPRI signals transmission impaired by intercore crosstalk in 5G network fronthauls with multicore fibers

The impact of intercore crosstalk (ICXT) of weakly-coupled multicore fibers (MCFs) on the transmission performance of a Common Public Radio Interface (CPRI) signal in 5G networks fronthaul is studied by numerical simulation. The results show that forward error correction-supported CPRI signals have more tolerance to ICXT due to the higher targeted bit error rate (of 10−3). For a receiver power penalty of 1 dB, an improvement of the tolerance of CPRI signals to ICXT, due to the increase of the MCF skew by about 1 dB, is observed. However, for the crosstalk levels that lead to 1 dB power penalty, we have shown that, the system is unavailable with a high probability. The crosstalk level required for an acceptable outage probability is about 10 dB lower than the crosstalk level leading to 1 dB power penalty.

Characteristics of homogeneous multi-core fibers for SDM transmission

We describe optical data transmission systems using homogeneous, single-mode, multi-core fibers (MCFs). We first briefly discuss space-division multiplexing (SDM) fibers, observing that no individual SDM fiber offers overwhelming advantages over bundles of single-mode fiber (SMF) across all transmission regimes. We note that for early adoption of SDM fibers, uncoupled or weakly coupled fibers which are compatible with existing SDM infrastructure have a practical advantage. Yet, to be more attractive than parallel SMF, it is also necessary to demonstrate benefits beyond improved spatial spectral efficiency. It is hoped that the lower spread of propagation delays (skew) between spatial channels in some fibers can be exploited for improved performance and greater efficiency from hardware sharing and joint processing. However, whether these benefits can be practically harnessed and outweigh impairments or effort to mitigate cross talk between spatial channels is not yet clear. Hence, focusing on homogeneous MCFs, we first describe measurements and simulations on the impact of inter-core cross talk in such fibers before reporting experimental investigation into the spatial channel skew variation with a series of the experimental results including a comparison with SMF in varying environmental conditions. Finally, we present some system and transmission experiments using parallel recirculating loops that enable demonstration of both multi-dimensional modulation and joint digital processing techniques across three MCF cores. Both techniques lead to increased transmission reach but highlight the need for further experimental analysis to properly characterize the potential benefits of correlated propagation delays in such fibers.

Performance Analysis of Core-Multiplexed Spectral Amplitude Coded OCDMA PON

Spatial division multiplexing is emerging as a promising solution to improve the optical fiber transmission capacity. In this paper, a multicore fiber (MCF)-based optical access network architecture utilizing spectral amplitude coded optical code division multiple access (SAC-OCDMA) is proposed. We numerically analyze the impact of intercore cross talk (XT) on the bit error probability (BEP) performance of the SAC-OCDMA signals where a closed-form formula for the BEP of the proposed network is derived. We also consider the effects of multiple access interference noise, optical beat noise, and receiver noise in the analysis. Through numerical simulations, we find the penalty in the required Q-factor caused by intercore XT, compared with a single-core system with no XT, for different values of mean intercore XT.

Reconfigurable Radio Access Networks Using Multicore Fibers

We propose the use of spatial division multiplexing supported by multicore fibers to implement a new generation of flexible and capacity reconfigurable cloud radio access network front-haul architectures capable of addressing their main present and future challenges. We show that for the majority of radio access scenarios where front-haul optical links are less than 10-km long, the impact of inter-core crosstalk on the electrical carrier-to-noise ratio can be neglected, and thus, link design can be carried independently core by core. In addition, this MCF-based approach, which is compatible with software defined networking and network function virtualization, can also support the integration of a passive optical network overlay.

CapEx advantages of multi-core fiber networks

We investigate capital expenditure (CapEx) advantages of multi-core fiber (MCF) networks by modeling and solving CapEx-minimized planning problem. Integer linear programming model is established, and numerical results are calculated and analyzed. We conduct the solving process under two kinds of traffic patterns of light traffic and heavy traffic. The influences of inter-core crosstalk on MCF and its multi-input multi-output (MIMO)-based crosstalk suppression are also evaluated. Numerical results show that when inter-core crosstalk in MCF is not considered, MCF networks have CapEx advantages under both given traffic patterns by using mixed MCF&SCF deployment strategy, despite the variation in MCF optical amplifier's price whose cost takes the largest share of the total network CapEx. However, when the inter-core crosstalk in MCF is taken into consideration, the costs of networks using MCF go higher than those of single-core fiber (SCF) networks. With the help of MIMO-based inter-core crosstalk suppression, the negative impact of inter-core crosstalk can be mitigated, and MCF can still show its CapEx advantages when the traffic load is heavy.