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A high-speed traveling wave electro-absorption modulator based on grapheme-micro fiber is designed. Graphene modulates the optical transmission intensity by changing its fermi level under different applied voltages. Graphene has an extremely high carrier mobility which has a potential electrical bandwidth of 500 GHz. However, the bandwidth of the state-of-art graphene based modulator is limited by...
We propose an inter-core crosstalk-aware routing, spectrum and core allocation scheme with spectrum bands and spatial Sp-Chs in multi-dimensional optical networks to get higher SE and lower XT. 15% reduction in XT is achieved.
In this paper, we investigate tradeoff between failure probability and load balancing in flexible bandwidth optical networks. We develop a tradeoff-principle algorithm (TPA) to improve spectrum efficiency and introduce a traditional algorithm (TA) for comparison. Simulation results show that TPA achieves better performance compared to TA.
The continued increase in Internet traffic, particularly in metro networks, is spurring wide deployment of optical networking technologies for wavelength routing. In metro networks, the number of nodes traversed can be very large and hence the optical filtering penalty incurred in the ROADM/OXC nodes can be critical as it degrades fiber frequency utilization. This presentation elucidates how grouped...
A real-time transport of fronthaul over a mix of analog and digital RoF is experimentally investigated. The obtained results show that up to 24 LTE channels can be transported with respect to the 3GPP requirements concerning EVM.
Telecom operators are racing towards upgrading their facilities and broadband services in order to meet the highly challenging 5G operational framework in dense urban landscapes. The oversubscribed sub-6 GHz wireless band is lacking the necessary bandwidth to support the envisioned 5G data rates, suggesting the transition to mm-wave bands as the only viable scenario. In conjunction with the cell densification...
We demonstrated the simultaneous transmission of multiband LTE-A signals, a WiFi IEEE802.11ac and a gigabit/s baseband 4-PAM signal over 1mm core diameter PMMA GI-POF. The optical link used a red light 650 nm laser diode and a p-i-n photodiode with a transimpedance amplifier. The 4-PAM transmission achieved 1.7 Gb/s (BER < 1×10−3), together with 9 LTE-A standard-compliant bands with EVM < 8%...
In this work, the loss and bandwidth performance of flexible multimode polymer waveguides are investigated under different launch conditions. It is shown that bending excess loss below 2 dB is achieved for radii larger than 3 mm for a 50 µm MMF input, and twisting excess loss below 0.6 dB for up to 1 full 360-degree turn even for a relatively overfilled launch. The bandwidth studies reveal that bending...
Multidimensional approach based on employment of both spatial and spectral modes in optical access networks can enable not only increase in the network throughput, but also enhance its dynamic and elastic behavior through spectral-spatial interworking and employment of an advanced software defined (SDN) networking model. In this paper we introduce the concept of virtual bandwidth exchange among end-users...
To support emerging traffic demands, metro optical networks evolve over time with the addition of new links to relieve network bottlenecks and congestion. These new resources need to be optimally located in the network, in order to minimize the cost of the new deployment. Spectrum-fragmentation and network-wide load imbalance impede the optimal allocation of network resources. With the recent convergence...
The telecom arena has become very competitive in dense urban areas where the number of potential customers as well as the requirement of high bandwidth are very important. Sparse areas, on the contrary, are left outside the broadband roll out due to the scarce expected revenues and high predicted investments. This work aims at comparing different architectures combining different technologies from...
By means of the dynamic and flexible choice of subcarrier modulation and spacing, frequency division multiplexing is demonstrated to overcome the system bandwidth limits achieving high capacity, both for datacenter interconnections and for multiple access passive optical networks.
The ever growing data volumes in the IT infrastructure can only by carried by the optical transmission technologies. The key requirements for such transmission systems are the small footprint, high energy efficiency and the low cost of ownership. One of the most promising candidates to realize the energy efficient high speed transmission over the short distance is transmission with the multi-mode...
Optical processing of radiofrequency signals is demonstrated in this communication using photoswitches made from nitrogen ion implanted InGaAs. The sampling device shows an ultrafast picosecond response time while activated by ultra-short optical pulses or modulated optical beam centered at the wavelength of 1.55 µm. The optoelectronic device is embedded in a microwave coplanar waveguide which has...
In this paper we investigate two promising approaches to reduce the optical bandwidth utilization in the mobile fronthaul of next-generation cloud radio access networks. We analyze and compare the performance of an analog radio-over-fiber and a new digital fronthaul in a chromatic dispersion-limited scenario. The former uses several analog channels, generated by up- and down-converting of baseband...
Low-power, ultrafast, all-optical switches have been developed by tuning the phase difference between transverse modes of a probe beam via intermodal cross-phase modulation (XPM) with a second beam as the control beam [1]. Switching energies in the nanojoule-regime were achieved in few-mode fibers [2].
Spatial eigenstates are a familiar part of optical waveguide theory. Such states enter and exit the waveguide as the same spatial state. As illustrated in Fig. 1. In the idealised case, a perfect waveguide, free of mode coupling, perturbations and ignoring chromatic dispersion, these spatial eigenstates also propagate with a single group-delay. However in reality, light propagation in multimode optical...
One of the most essential building blocks in modem electronics is the flip-flop. A flip-flop operates bi-stably between two states, remaining at a given output level (high or low level) until a specific input control signal changes. For many years, photonics has attempted to build all-optical flip-flops [1-3]; however, the success of these approaches has usually been limited by the dependence of the...
Photoacoustic imaging and optical coherence tomography (OCT) are the fastest growing fields in biomedical imaging. Supercontinuum (SC) sources offer great advantages to both of these modalities however, currently no suitable source has been developed to answer the requirements for both multispectral photoacoustic microscopy (MPAM) and OCT, i.e. a SC source with more than 50 nJ per bandwidth of less...
We provide the first demonstration of a high-bandwidth, low-intensity fiberized all-optical gate exploiting coherent absorption in a plasmonic metamaterial film. The fully packaged fiberized version of the switch has been tested to the bandwidth of 1 GHz while free-space versions of the gate have been shown to provide 100 THz bandwidth and to operate at arbitrarily low intensities. Our work illustrates...
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