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D. W. Peckham

Bio: D. W. Peckham is an academic researcher. The author has contributed to research in topics: Wavelength-division multiplexing & Quadrature amplitude modulation. The author has an hindex of 21, co-authored 32 publications receiving 2386 citations.

Papers
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Journal ArticleDOI
TL;DR: In this article, simultaneous transmission of six spatial and polarization modes, each carrying 40 Gb/s quadrature-phase-shift-keyed channels over 96 km of a low-differential group delay few-mode fiber, is reported.
Abstract: We report simultaneous transmission of six spatial and polarization modes, each carrying 40 Gb/s quadrature-phase-shift-keyed channels over 96 km of a low-differential group delay few-mode fiber. The channels are successfully recovered by offline DSP based on coherent detection and multiple-input multiple-output processing. A penalty of ;28 dB.

901 citations

Proceedings ArticleDOI
06 Mar 2011
TL;DR: In this article, the authors demonstrate the transmission of 6 independent, spatially and polarization multiplexed 28-Gb/s QPSK signals over 10 km of three-mode fiber using mode-selective excitation and full coherent 6 × 6 MIMO processing.
Abstract: We demonstrate the transmission of 6 independent, spatially- and polarization multiplexed 28-Gb/s QPSK signals over 10 km of three-mode fiber using mode-selective excitation and full coherent 6 × 6 MIMO processing.

277 citations

Journal ArticleDOI
TL;DR: In this paper, a coherent optical orthogonal frequency-division multiplexing (CO-OFDM) scheme with reduced guard interval (RGI) was proposed for high-speed high-spectral-efficiency long-haul optical transmission.
Abstract: We propose a novel coherent optical orthogonal frequency-division multiplexing (CO-OFDM) scheme with reduced guard interval (RGI) for high-speed high-spectral-efficiency long-haul optical transmission. In this scheme, fiber chromatic dispersion is compensated for within the receiver rather than being accommodated by the guard interval (GI) as in conventional CO-OFDM, thereby reducing the needed GI, especially when fiber dispersion is large. We demonstrate the generation of a 448-Gb/s RGI-CO-OFDM signal with 16-QAM subcarrier modulation through orthogonal band multiplexing. This signal occupies an optical bandwidth of 60 GHz, and is transmitted over 2000 km of ultra-large-area fiber (ULAF) with five passes through an 80-GHz-grid wavelength-selective switch. Banded digital coherent detection with two detection bands is used to receive this 448-Gb/s signal. Wavelength-division multiplexed transmission of three 80-GHz spaced 448-Gb/s RGI-CO-OFDM channels is also demonstrated, achieving a net system spectral efficiency of 5.2 b/s/Hz and a transmission distance of 1600 km of ULAF.

178 citations

Journal ArticleDOI
TL;DR: In this paper, the authors report the successful transmission of 64 Tb/s capacity (640 ×107 Gb/S with 12.5 GHz channel spacing) over 320 km reach utilizing 8-THz of spectrum in the C+L -bands at a net spectral efficiency of 8 bit/s/Hz.
Abstract: We report the successful transmission of 64 Tb/s capacity (640 ×107 Gb/s with 12.5 GHz channel spacing) over 320 km reach utilizing 8-THz of spectrum in the C+L -bands at a net spectral efficiency of 8 bit/s/Hz. Such a result is accomplished by the use of raised-cosine pulse-shaped PDM-36QAM modulation, intradyne detection, both pre- and post-transmission digital equalization, and ultra-large-area fiber. We discuss in detail the digital modulation technology and signal processing algorithms used in the experiment, including a new two-stage, blind frequency-search-based frequency-offset estimation algorithm and a more computationally efficient carrier-phase recovery algorithm.

139 citations

Journal ArticleDOI
TL;DR: In this article, the authors reported the successful transmission of ten 494.85 Gbit/s DWDM signals on the standard 50 GHz ITU-T grid over 32 × 100 km of ultra-large-area (ULA) fiber.
Abstract: We report the successful transmission of ten 494.85 Gbit/s DWDM signals on the standard 50 GHz ITU-T grid over 32 × 100 km of ultra-large-area (ULA) fiber. A net spectral efficiency (SE) of 8.25 b/s/Hz was achieved, after excluding the 20% soft-decision forward-error-correction (FEC) overhead. Such a result was accomplished by the use of a recently proposed polarization-division-multiplexed (PDM) time-domain hybrid 32-64 quadrature-amplitude-modulation (QAM) format, along with improved carrier frequency and phase recovery algorithms. It is shown that time-domain hybrid QAM provides a new degree of design freedom to optimize the transmission performance by fine tuning the SE of the modulation format for a specific channel bandwidth and FEC redundancy requirement. In terms of carrier recovery, we demonstrate that 1) hardware efficient estimation and tracking of the frequency offset between the signal and local-oscillator (LO) can be achieved by using a new feedback-based method, and 2) a training-assisted two-stage phase estimation algorithm effectively mitigates cyclic phase slipping problems. This new phase recovery algorithm not only improves the receiver sensitivity by eliminating the need for differential coding and decoding, but also enables an additional equalization stage following the phase recovery. We have shown that the introduction of this additional equalization stage (with larger number of taps) helps reduce the implementation penalty. This paper also presents the first experimental study of the impact of inphase (I) and quadrature (Q) correlation for a high-order QAM. It is shown that an adaptive equalizer could exploit the correlation between I and Q signal components to artificially boost the performance by up to 0.7 dB for a PDM time-domain hybrid 32-64 QAM signal when the equalizer length is significantly longer than I/Q de-correlation delay.

123 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper, the authors demonstrate the ability to multiplex and transfer data between twisted beams of light with different amounts of orbital angular momentum, which provides new opportunities for increasing the data capacity of free-space optical communications links.
Abstract: Researchers demonstrate the ability to multiplex and transfer data between twisted beams of light with different amounts of orbital angular momentum — a development that provides new opportunities for increasing the data capacity of free-space optical communications links.

3,556 citations

Journal ArticleDOI
TL;DR: In this paper, the authors summarized the simultaneous transmission of several independent spatial channels of light along optical fibres to expand the data-carrying capacity of optical communications, and showed that the results achieved in both multicore and multimode optical fibers are documented.
Abstract: This Review summarizes the simultaneous transmission of several independent spatial channels of light along optical fibres to expand the data-carrying capacity of optical communications. Recent results achieved in both multicore and multimode optical fibres are documented.

2,629 citations

Journal ArticleDOI
28 Jun 2013-Science
TL;DR: The viability of using the orbital angular momentum (OAM) of light to create orthogonal, spatially distinct streams of data-transmitting channels that are multiplexed in a single fiber is demonstrated and suggest that OAM could provide an additional degree of freedom for data multiplexing in future fiber networks.
Abstract: Internet data traffic capacity is rapidly reaching limits imposed by optical fiber nonlinear effects Having almost exhausted available degrees of freedom to orthogonally multiplex data, the possibility is now being explored of using spatial modes of fibers to enhance data capacity We demonstrate the viability of using the orbital angular momentum (OAM) of light to create orthogonal, spatially distinct streams of data-transmitting channels that are multiplexed in a single fiber Over 11 kilometers of a specially designed optical fiber that minimizes mode coupling, we achieved 400-gigabits-per-second data transmission using four angular momentum modes at a single wavelength, and 16 terabits per second using two OAM modes over 10 wavelengths These demonstrations suggest that OAM could provide an additional degree of freedom for data multiplexing in future fiber networks

2,343 citations

Journal ArticleDOI
TL;DR: In this article, simultaneous transmission of six spatial and polarization modes, each carrying 40 Gb/s quadrature-phase-shift-keyed channels over 96 km of a low-differential group delay few-mode fiber, is reported.
Abstract: We report simultaneous transmission of six spatial and polarization modes, each carrying 40 Gb/s quadrature-phase-shift-keyed channels over 96 km of a low-differential group delay few-mode fiber. The channels are successfully recovered by offline DSP based on coherent detection and multiple-input multiple-output processing. A penalty of ;28 dB.

901 citations

Journal ArticleDOI
05 Jun 2006
TL;DR: This paper discusses the generation and detection of multigigabit/s intensity- and phase-modulated formats, and highlights their resilience to key impairments found in optical networking, such as optical amplifier noise, multipath interference, chromatic dispersion, polarization-mode dispersion.
Abstract: Fiber-optic communication systems form the high-capacity transport infrastructure that enables global broadband data services and advanced Internet applications. The desire for higher per-fiber transport capacities and, at the same time, the drive for lower costs per end-to-end transmitted information bit has led to optically routed networks with high spectral efficiencies. Among other enabling technologies, advanced optical modulation formats have become key to the design of modern wavelength division multiplexed (WDM) fiber systems. In this paper, we review optical modulation formats in the broader context of optically routed WDM networks. We discuss the generation and detection of multigigabit/s intensity- and phase-modulated formats, and highlight their resilience to key impairments found in optical networking, such as optical amplifier noise, multipath interference, chromatic dispersion, polarization-mode dispersion, WDM crosstalk, concatenated optical filtering, and fiber nonlinearity

772 citations