Giorgio Maria Tosi Beleffi

Bio: Giorgio Maria Tosi Beleffi is an academic researcher from Ministry of Economic Development. The author has contributed to research in topics: Passive optical network & Wavelength-division multiplexing. The author has an hindex of 9, co-authored 46 publications receiving 311 citations. Previous affiliations of Giorgio Maria Tosi Beleffi include University of Rome Tor Vergata.

Optical wireless transmission at 1.6-Tbit/s (16×100 Gbit/s) for next-generation convergent urban infrastructures

Abstract: We present a high-data rate optical wireless system. The implemented system exploits polarization (PM) and wavelength multiplexing, achieving the transmission of a total capacity of 1.6 Tbit/s over hybrid fiber free-space optics (FSO) system with no optical-electronic-optical conversion at the interfaces with air. Quadrature phase shift keying modulation in each channel and coherent detection were used. The system allows enough power budget to support the record transmission of 16 channels, operating each at 100 Gbit/s over 40 km of fiber and 80 m of FSO between two buildings. Performance of the fully transparent connection is presented in terms of bit-error rate.

Demonstration of a Remotely Dual-Pumped Long-Reach PON for Flexible Deployment

Abstract: We propose and experimentally demonstrate a flexible wavelength division multiplexing/time division multiplexing network architecture for converged metro-access environment. Entire passiveness in the fiber plant is achieved with remote amplification in the signal distribution nodes along the metro ring and in the power splitters of the local access tree. We assist a traditional remote pumping scheme with a distributed pump provided by the optical network units and demonstrate that loss budgets beyond 30 dB can be supported. Data transmission of up to 10 Gb/s is evaluated in different deployment scenarios, reaching from a 78 km long reach rural to a dense 1:128 split/λ urban configuration with field installed fibers, including also worst case resilience configurations.

All-Optical Conversion From RZ to NRZ Using Gain-Clamped SOA

Abstract: An all-optical converter from return-to-zero (RZ) pulses to the nonreturn-to-zero (NRZ) format is presented. The converter operates in two stages: the laser generated in a gain-clamped semiconductor optical amplifier (SOA) is modulated with the data signal; afterwards this signal is wavelength-converted by cross-gain modulation in a common SOA. The setup is noninverting and can feature wavelength conversion. Experimental error-free conversion from 5- and 40-ps RZ pulses to NRZ format is presented at 10 Gb/s using a 211-1 bit sequence

Improved remote node configuration for passive ring-tree architectures

Abstract: In this paper, a set of optically fed passive remote node configurations for a ring-tree extended reach PON which allow increased efficiency and resilience are presented.

Ultra-High-Capacity Passive Optical Network Systems with Free-Space Optical Communications

Abstract: This article experimentally demonstrates a hybrid fiber–free-space passive optical network that enables high spectral density, aggregated capacity, and total throughput through ultra-dense wavelength-division multiplexing baseband and radio-over-fiber channels. Ultra-dense wavelength-division multiplexing 10-Gb/s Nyquist-shaped 16-ary quadrature amplitude modulation, 10-Gb/s radio-over-fiber orthogonal frequency-division multiplexing, and 8.75-Gb/s baseband orthogonal frequency-division multiplexing signals per user were transmitted through a maximum 40-km passive optical network, which includes a 6-m free-space optics link with acceptable performance.

Emerging Optical Wireless Communications-Advances and Challenges

Abstract: New data services and applications are emerging continuously and enhancing the mobile broadband experience. The ability to cope with these varied and sophisticated services and applications will be a key success factor for the highly demanding future network infrastructure. One such technology that could help address the problem would be optical wireless communications (OWC), which presents a growing research interest in the last few years for indoor and outdoor applications. This paper is an overview of the OWC systems focusing on visible light communications, free space optics, transcutaneous OWC, underwater OWC, and optical scattering communications.

Toward an Efficient C-RAN Optical Fronthaul for the Future Networks: A Tutorial on Technologies, Requirements, Challenges, and Solutions

Abstract: The exponential traffic growth, demand for high speed wireless data communications, as well as incessant deployment of innovative wireless technologies, services, and applications, have put considerable pressure on the mobile network operators (MNOs). Consequently, cellular access network performance in terms of capacity, quality of service, and network coverage needs further considerations. In order to address the challenges, MNOs, as well as equipment vendors, have given significant attention to the small-cell schemes based on cloud radio access network (C-RAN). This is due to its beneficial features in terms of performance optimization, cost-effectiveness, easier infrastructure deployment, and network management. Nevertheless, the C-RAN architecture imposes stringent requirements on the fronthaul link for seamless connectivity. Digital radio over fiber-based common public radio interface (CPRI) is the fundamental means of distributing baseband samples in the C-RAN fronthaul. However, optical links which are based on CPRI have bandwidth and flexibility limitations. Therefore, these limitations might constrain or make them impractical for the next generation mobile systems which are envisaged not only to support carrier aggregation and multi-band but also envisioned to integrate technologies like millimeter-wave (mm-wave) and massive multiple-input multiple-output antennas into the base stations. In this paper, we present comprehensive tutorial on technologies, requirements, architectures, challenges, and proffer potential solutions on means of achieving an efficient C-RAN optical fronthaul for the next-generation network such as the fifth generation network and beyond. A number of viable fronthauling technologies such as mm-wave and wireless fidelity are considered and this paper mainly focuses on optical technologies such as optical fiber and free-space optical. We also present feasible means of reducing the system complexity, cost, bandwidth requirement, and latency in the fronthaul. Furthermore, means of achieving the goal of green communication networks through reduction in the power consumption by the system are considered.

Optical Wireless Communications: An Emerging Technology

Abstract: This book focuses on optical wireless communications (OWC), an emerging technology with huge potential for the provision of pervasive and reliable next-generation communications networks. It shows how the development of novel and efficient wireless technologies can contribute to a range of transmission links essential for the heterogeneous networks of the future to support various communications services and traffic patterns with ever-increasing demands for higher data-transfer rates. The book starts with a chapter reviewing the OWC field, which explains different sub-technologies (visible-light, ultraviolet (UV) and infrared (IR) communications) and introduces the spectrum of application areas (indoor, vehicular, terrestrial, underwater, intersatellite, deep space, etc.). This provides readers with the necessary background information to understand the specialist material in the main body of the book, which is in four parts. The first of these deals with propagation modelling and channel characterization of OWC channels at different spectral bands and with different applications. The second starts by providing a unified information-theoretic treatment of OWC and then discusses advanced physical-layer methodologies (including, but not limited to: advanced coding, modulation diversity, cooperation and multi-carrier techniques) and the ultimate limitations imposed by practical constraints. On top of the physical layer come the upper-layer protocols and cross-layer designs that are the subject of the third part of the book. The last part of the book features a chapter-by-chapter assessment of selected OWC applications. Optical Wireless Communications is a valuable reference guide for academic researchers and practitioners concerned with the future development of the worlds communication networks. It succinctly but comprehensively presents the latest advances in the field.

Multiuser Relaying over Mixed RF/FSO Links

Abstract: A multiuser dual-hop relaying system over mixed radio frequency/free-space optical (RF/FSO) links is investigated. Specifically, the system consists of m single-antenna sources, a relay node equipped with n≥ m receive antennas and a single photo-aperture transmitter, and one destination equipped with a single photo-detector. RF links are used for the simultaneous data transmission from multiple sources to the relay. The relay operates under the decode-and-forward protocol and utilizes the popular V-BLAST technique by successively decoding each user's transmitted stream. Two common norm-based orderings are adopted, i.e., the streams are decoded in an ascending or a descending order. After V-BLAST, the relay retransmits the decoded information to the destination via a point-to-point FSO link in m consecutive timeslots. Analytical expressions for the end-to-end outage probability and average symbol error probability of each user are derived, while closed-form asymptotic expressions are also presented. Capitalizing on the derived results, some engineering insights are manifested, such as the coding and diversity gain of each user, the impact of the pointing error displacement on the FSO link and the V-BLAST ordering effectiveness at the relay.

Roadmap to free space optics

Abstract: With the ever-increasing demand for data and the radio frequency spectrum becoming congested, free space optics (FSO) may find a niche for situations where fiber is too expensive or too difficult to install. FSO is a cross-disciplinary field that draws from radio and fiber communication, astronomy, and even quantum optics, and it has seen major advances over the last three decades. In this tutorial-style review, we provide a broad overview of many of the important topics required to design, develop, and research the next generation of FSO technology.