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The development of advanced InP-based transmitter PICs of increasing complexity and integrating periodically capacitive-loaded (CL) Travelling Wave Electrode (TWE) Mach-Zehnder modulators is reported and discussed in examples.
In contrast to the more prominent discrete-variable quantum key distribution (DV-QKD), which requires specialized hardware like single-photon detectors, the continuous-variable version (CV-QKD) promises low-cost and high-performance implementations by leveraging mature telecommunication technology. In this paper we demonstrate a simplified CV-QKD architecture based on analog frontends and digitizers...
In this paper, we propose an adaptive software-defined optical sensor network (SDOSN) architecture that is capable to host programmable sensors ranging from several thousands to several millions. Sensing process is of low cost, but highly accurate and capable of closely approaching the optical channel capacity. The proposed SDOSN architecture is interoperable with existing optical networks infrastructure...
An eight-channel multi-format coherent optical transceiver is proposed as an alternative to implement terabit metro inter-data centre interconnects (DCI) transmitting from 800 to 1600 Gb/s over conventional single mode fibre (CSMF). The maximum reach of the system as a function of transmitted power and overall capacity is numerically estimated for a BER target of 1×10−13, avoiding the use of optical...
The distribution and use of network resources should be evaluated in order to reduce the computational and financial costs incurred in the deployment and maintenance of the network. This work presents a methodology for cost-benefit evaluation of different regenerator placement and allocation techniques for elastic optical networks. The proposed methodology is applied in scenarios with dynamic traffic...
In this paper, we propose, design, and evaluate the use of transmitters mapping with a symbols encoding techniques to mitigate inter-symbol interference (ISI) and improve the overall VLC system performance while using a very simple receiver (single element wide field of view, (FOV)) with an OOK modulation scheme. The proposed technique with the laser diodes transmitters are able to provide data rates...
Digital transmission over dispersive optical channels suffers from intersymbol interference (ISI).We study themutual information of PAM transmission under the intensity modulation and direct detection (IM/DD) constraint, where we model the optical channel as a Gaussian low-pass filter, which is a valid attempt for polymer optical fibers (POF) and allows closed form expressions. In particular, we study...
In this invited paper, we present utilization of free-space optical (FSO) link in overcoming a connectivity gap between the backbone and last mile access networks. The non-line-of-sight area is bridged by radio frequency (RF) link by employing relaying technology, while the FSO link is used to deliver transmission from the relay to the end user. Firstly, a brief recapitulation of main results in the...
We introduce physical-layer network coding for a passive optical interconnect architecture in datacenter networks. Results reveal that half of the wavelengths can be saved to obtain latency in the magnitude of microseconds.
We review alternative solutions for optical fronthauling in next generation fixed-mobile converged architectures that try to solve the problems related to the extremely high bit rates required by current fronthauling implementations based on the so-called digitized Radio over Fiber (as for the CPRI or OBSAI standards). In particular, we present our most recent results on Digital Signal Processing...
This paper demonstrates a multi-hop underwater visible light communication (VLC) system using light emitting diodes (LEDs). It is demonstrated that using a multi-hop technique, the overall underwater VLC distance can be increased significantly without adding significant complexity to the physical layer. The performance of the multi-hop system is compared to a single-hop technique utilizing three types...
We present a robust adaptive digital pre-distortion technique to mitigate the linear and non-linear degradation of optical communication transmitter components. The proposed method is based on the principles of memory polynomial based pre-distortion and indirect learning architecture. Effectiveness of the presented algorithm is assessed across various higher order modulation formats and higher baud...
The performance of visible light communication (VLC) systems, adopting hybrid modulation techniques, is investigated under dynamic fading channels. Hybrid M-ary quadrature amplitude modulation and multi-pulse pulse-position modulation (hybrid QAM-MPPM) scheme is considered because of its high-power efficiency under constrained spectral efficiency. Expressions for bit-error rate (BER) and outage probability...
WDM has been generally proposed to groom wavelengths for transport applications. This paper will describe our attempt to reduce cost and energy consumption of smart network elements, through an extended use of WDM techniques at the data link level. This paper will draw the advantages of this approach and will demonstrate that this new direction is efficient to keep the frequency processing at a reasonable...
We report on the design and experimental characterization of a novel pair of underwater wireless optical modems. Each of them is equipped with a blue LED array as transmitter, an APD photodiode as receiver and a pin photodiode for optical power monitoring. The modems are designed to operate at 10 Mbit/s (10BaseT Ethernet, Manchester-coded signal) in harsh conditions, i.e. in turbid water and with...
This work investigates the estimation accuracy of a coherent optical transmission system's performance when the number of spans in the system is known and the overall system length is approximately known. However, there is no knowledge of the lengths of the individual spans as may happen when institutional knowledge of deployed fibre is lost. Estimating the performance of an optical signal over systems...
The availability of low cost commercially available components operating at 60 GHz, mainly driven by the approval of the consumer oriented IEEE 802.11ad and 802.15.3c standards, is expected to boost the deployment of 60 GHz wireless networks where an unlicensed band with around 7 GHz bandwidth is available. Nevertheless, the transmission of 60 GHz wireless signals is limited to a few meters (∼10 m),...
In this paper, we demonstrate a reconfigurable optical orthogonal frequency division multiplexing (OFDM) signal transmitter based on a sliced broadband amplified spontaneous emission (ASE) optical source for directly detected (DD) multiband OFDM next generation wavelength division multiplexed (WDM) access networks. Theoretical predictions and experimental demonstrations validate the feasibility of...
We report on the role of digital pre-emphasis in facilitating 64 Gbaud DP-64QAM coherent optical systems based on currently available commercial 32 Gbaud transceiver components. In particular, we vary the extent of digital pre-emphasis together with digital-to-analog converter bandwidth and resolution, and show the optical back-to-back performance and transmitter output power trade-offs. Our results...
The relentless traffic growth in datacenter networks is stimulating the adoption of pioneering optical interconnect technologies as well as their integration with novel network and switching architectures. Even more, the need for disaggregation of data storage and processing resources significantly increases the capacity and dimensioning requirements of such networks. In this context, a novel datacenter...
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