"As data center traffic increases, challenges rise for existing optical transceivers. For data center interconnects (DCIs) transmission distance matters and drives specifications of optical transceivers. For metro and long reach DCIs (>100 km), high bit rate and small form factor is imperative for next-generation transceiver. The advent of high speed digital-to-analog (DAC) and analog-to-digital converters (ADC), and recent progress in complementary metal-oxide-semiconductor (CMOS) as well as in integrated photonic technology has facilitated the development of optical transceivers relying on coherent detection employing digital signal processing (DSP). On extended reach DCIs (

"The burgeoning capacity demand for both optical transport links over metro / long-haul distances (> 100km) and short reach optical interconnects (100m-20km) for inter- and intra-datacenter networking is driving the notion of a digital signal processing (DSP) based optical transceiver. In optical transport, flexible optical transceivers employ coherent detection and DSP to enable mitigating various fiber transmission impairments such as chromatic dispersion (CD), polarization mode dispersion (PMD), Kerr nonlinearity, laser phase noise and frequency offset. In addition, these flexible transceivers need to be agile enough to adapt to the increasingly dynamic network traffic needs (e.g. varying capacity and reach requirements, dynamic wavelength assignments). On the short reach side, cheap and power efficient optics is a necessity for datacenter applications and hence intensity modulation / direct-detection (IM/DD) prevails over coherent detection. For such IM/DD transceivers, photonic integration is envisioned to play a significant role in reducing the cost along with DSP that potentially allows increasing the delivered bit rates with cheap electronics and reduced number of optical components (and consequently footprint).In the first part of the thesis, we propose and verify, both analytically and experimentally, a myriad of DSP algorithms suitable for implementation in flexible optical coherent transceivers for transport networks. The proposed DSP algorithms tackle impairments such as laser phase noise, frequency offset, polarization rotation, fiber Kerr nonlinearity and sampling frequency offset. For each of the proposed algorithms, we provide a performance comparison with the standard counterparts in the literature highlighting the advantages of our approaches together with the underlying tradeoffs. Next, we develop and experimentally verify a rigorously derived analytical model for performance evaluation of a flexible coherent optical front-end that can operate colorlessly in a wavelength division multiplexing (WDM) scenario, i.e. without the need for a WDM demultiplexing filter prior to the receiver. The accuracy of the developed model was proved by finding a close match between model predictions and experimental results. We finally show that the model can be used as a useful system design tool to predict the system performance at various operating scenarios.In the last part of the thesis, we propose a DSP algorithm to enable polarization division multiplexing (PDM) in IM/DD transceivers for short reach optical interconnects. This doubles the achievable bit rate with the same speed of the electronic components and with the same number of light sources by exploiting the two orthogonal polarization states per source. The proposed DSP algorithm is based on a multiple-input and multiple-output (MIMO) finite impulse response (FIR) filter that operates on the Stokes parameters of the received field, which can be obtained via a direct-detection receiver front-end, to invert the random rotations that occurred along the fiber. The proposed DSP was verified experimentally using an IM/DD transceiver that employs a single 1310 nm laser whose both polarizations were modulated by a packaged silicon photonic (SiP) intensity modulator. A record bit rate of 224 Gb/s was transmitted over 10 km with a BER below the forward-error-correcting (FEC) threshold." --

With optical fiber telecommunications firmly entrenched in the global information infrastructure, a key question for the future is how deeply will optical communications penetrate and complement other forms of communication (e.g., wireless access, on-premises networks, interconnects, and satellites). Optical Fiber Telecommunications, the seventh edition of the classic series that has chronicled the progress in the research and development of lightwave communications since 1979, examines present and future opportunities by presenting the latest advances on key topics such as: Fiber and 5G-wireless access networks Inter- and intra-data center communications Free-space and quantum communication links Another key issue is the use of advanced photonics manufacturing and electronic signal processing to lower the cost of services and increase the system performance. To address this, the book covers: Foundry and software capabilities for widespread user access to photonic integrated circuits Nano- and microphotonic components Advanced and nonconventional data modulation formats The traditional emphasis of achieving higher data rates and longer transmission distances are also addressed through chapters on space-division-multiplexing, undersea cable systems, and efficient reconfigurable networking. This book is intended as an ideal reference suitable for university and industry researchers, graduate students, optical systems implementers, network operators, managers, and investors. Quotes: "This book series, which owes much of its distinguished history to the late Drs. Kaminow and Li, describes hot and growing applied topics, which include long-distance and wideband systems, data centers, 5G, wireless networks, foundry production of photonic integrated circuits, quantum communications, and AI/deep-learning. These subjects will be highly beneficial for industrial R&D engineers, university teachers and students, and funding agents in the business sector." Prof. Kenichi Iga President (Retired), Tokyo Institute of Technology "With the passing of two luminaries, Ivan Kaminow and Tingye Li, I feared the loss of one of the premier reference books in the field. Happily, this new version comes to chronicle the current state-of-the-art and is written by the next generation of leaders. This is a must-have reference book for anyone working in or trying to understand the field of optical fiber communications technology." Dr. Donald B. Keck Vice President, Corning, Inc. (Retired) "This book is the seventh edition in the definitive series that was previously marshaled by the extraordinary Ivan Kaminow and Tingye Li, both sadly no longer with us. The series has charted the remarkable progress made in the field, and over a billion kilometers of optical fiber currently snake across the globe carrying ever-increasing Internet traffic. Anyone wondering about how we will cope with this incredible growth must read this book." Prof. Sir David Payne Director, Optoelectronics Research Centre, University of Southampton Updated edition presents the latest advances in optical fiber components, systems, subsystems and networks Written by leading authorities from academia and industry Gives a self-contained overview of specific technologies, covering both the state-of-the-art and future research challenges

Presenting the cutting-edge results of new device developments and circuit implementations, High-Speed Devices and Circuits with THz Applications covers the recent advancements of nano devices for terahertz (THz) applications and the latest high-speed data rate connectivity technologies from system design to integrated circuit (IC) design, providing relevant standard activities and technical specifications. Featuring the contributions of leading experts from industry and academia, this pivotal work: Discusses THz sensing and imaging devices based on nano devices and materials Describes silicon on insulator (SOI) multigate nanowire field-effect transistors (FETs) Explains the theory underpinning nanoscale nanowire metal-oxide-semiconductor field-effect transistors (MOSFETs), simulation methods, and their results Explores the physics of the silicon-germanium (SiGe) heterojunction bipolar transistor (HBT), as well as commercially available SiGe HBT devices and their applications Details aspects of THz IC design using standard silicon (Si) complementary metal-oxide-semiconductor (CMOS) devices, including experimental setups for measurements, detection methods, and more An essential text for the future of high-frequency engineering, High-Speed Devices and Circuits with THz Applications offers valuable insight into emerging technologies and product possibilities that are attractive in terms of mass production and compatibility with current manufacturing facilities.

This book focuses on recent research and developments on optical communications. The chapters present different aspects of optical communication systems, comprising high capacity transmission over long distances, coherent and intensity modulated technologies, orthogonal frequency-division multiplexing, ultrafast switching techniques, and photonic integrated devices. Digital signal processing and error correction techniques are also addressed. The content is of interest to graduate students and researchers in optical communications.