By Topic

Lightwave Technology, Journal of

Issue 7 • Date July 2006

Filter Results

Displaying Results 1 - 25 of 56
  • [Front cover]

    Publication Year: 2006 , Page(s): c1
    Save to Project icon | Request Permissions | PDF file iconPDF (273 KB)  
    Freely Available from IEEE
  • Journal of Lightwave Technology publication information

    Publication Year: 2006 , Page(s): c2
    Save to Project icon | Request Permissions | PDF file iconPDF (38 KB)  
    Freely Available from IEEE
  • Table of contents

    Publication Year: 2006 , Page(s): 2481 - 2483
    Save to Project icon | Request Permissions | PDF file iconPDF (58 KB)  
    Freely Available from IEEE
  • Guest Editorial Optical Signal Processing

    Publication Year: 2006 , Page(s): 2484 - 2486
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | PDF file iconPDF (938 KB)  
    Freely Available from IEEE
  • Optical arbitrary waveform generation and characterization using spectral line-by-line control

    Publication Year: 2006 , Page(s): 2487 - 2494
    Cited by:  Papers (11)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (264 KB) |  | HTML iconHTML  

    This paper demonstrates optical arbitrary waveform generation (O-AWG) and its characterization using spectral line-by-line control with high-resolution grating-based pulse shapers. Such integrated capabilities are the enabling techniques for high-fidelity O-AWG. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Filling the frequency gaps of a planar optical spectrum analyzer using a 2.5-GHz-spaced arrayed-waveguide grating in the C and L bands

    Publication Year: 2006 , Page(s): 2495 - 2499
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (296 KB)  

    A vernier configuration in a 2.5-GHz-spaced 128-channel arrayed-waveguide grating (AWG) for use as a secondary demultiplexer in a planar optical spectrum analyzer was incorporated with a tandem configuration. The frequency changes were 3.0 and 2.5 GHz for adjacent input and output ports, respectively. By selecting any of the eight input ports of the AWG, new passbands could be generated in the gaps between adjacent passbands and in the gaps produced when the diffraction order of the AWG was changed. Enough new passbands were generated to achieve frequency sampling at 1-GHz intervals without dead frequency points in the C and L bands of optical fiber amplifiers. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Photonic microwave tunable single-bandpass filter based on a Mach-Zehnder interferometer

    Publication Year: 2006 , Page(s): 2500 - 2509
    Cited by:  Papers (50)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (368 KB)  

    The authors present the theoretical analysis and experimental demonstration of a novel single-bandpass tunable microwave filter. The filter is based on a broadband optical source and a fiber Mach-Zehnder interferometer and shows a high Q factor over a tuning range of 5-17 GHz. A generalized analysis considering that the optical signal propagates along optical delay lines with a dispersion slope different from zero is presented. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optical pulse compression based on stationary rescaled pulse propagation in a comblike profiled fiber

    Publication Year: 2006 , Page(s): 2510 - 2522
    Cited by:  Papers (6)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (416 KB)  

    In this paper, optical pulse compression using a comblike profiled fiber (CPF) is theoretically and experimentally studied, in which highly nonlinear fibers and single-mode fibers are alternately concatenated. Stationary rescaled pulse (SRP), is the main focus, which is a recently discovered nonlinear stationary pulse in CPF. The fundamental characteristics of SRP are investigated, and SRP propagation is applied to the design of the CPF pulse compressor. Using the proposed design method, the specifications of the CPF can easily be controlled, such as the compression ratio per step of the CPF or the pedestal of the output pulse. Two experimental results of pulse compression using the CPF based on the proposed design method are shown: 1) pulse compression with a large compression ratio per step of the CPF and 2) low-pedestal and wideband wavelength-tunable compression. A parametric noise-amplification phenomenon occurring in a compression process for an optical pulse sequence is also numerically analyzed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Coherent photonic processing of microwave signals using spatial light modulators: programmable amplitude filters

    Publication Year: 2006 , Page(s): 2523 - 2529
    Cited by:  Papers (16)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (416 KB) |  | HTML iconHTML  

    This paper presents a novel coherent optical signal processing approach for synthesis of programmable microwave amplitude filters over an ultrawideband. The authors' scheme relies on a programmable hyperfine optical filter implemented in a pulse-shaping geometry, which provides arbitrary, user-defined amplitude-filtering functions over a 50-GHz bandwidth with resolution better than 0.7 GHz. In contrast to previous work on discrete time optical processing of microwave signals, their approach allows direct synthesis of microwave filter functions in spectral domain without computing filter coefficients, which is needed for a discrete-time-domain approach. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optical adaptive equalization of high-speed signals using time-domain optical Fourier transformation

    Publication Year: 2006 , Page(s): 2530 - 2540
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (400 KB) |  | HTML iconHTML  

    This paper describes a new distortion-free optical transmission method that can eliminate any kind of linear perturbation including jitter, polarization-mode dispersion, and higher order dispersion as well as time-varying dispersion. This method uses transform-limited pulses and time-domain optical Fourier transformation (OFT). With this technique, particular attention is given to the spectral envelope profile of the transmitted signal, which is unchanged regardless of the type and magnitude of the linear perturbation in the transmission fiber. OFT converts the unchanged spectral profile into the time domain and allows to obtain undistorted original waveforms at the output. Experimental and analytical results to show the effectiveness of this method are presented, especially when the method is applied to high-speed signals up to 160 Gb/s, which are sensitive to both higher order and time-varying dispersions. This paper also describes a new all-optical time-domain Fourier transformation technique that uses an optical parabolic pulse. This technique is promising, with a view to improving the elimination of distortion at 160 Gb/s and above. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Synthesis of optical-coherence function and its applications in distributed and multiplexed optical sensing

    Publication Year: 2006 , Page(s): 2541 - 2557
    Cited by:  Papers (15)  |  Patents (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2128 KB)  

    We have proposed and demonstrated in recent years a unique technique to synthesize the optical-coherence function by manipulating the frequency and the phase of lightwave. Based upon this technique, the synthesis of optical coherence function (SOCF), various distributed photonic sensing and optical-information-processing applications have been developed. In this paper, the principle of SOCF is summarized. A series of functional optical-sensing systems, including fiber-optic reflectometries, distributed stress-location sensors, multiplexed fiber Bragg grating (FBG) sensors, are introduced. Fully distributed fiber-optic strain sensing systems by Brillouin frequency shift are highlighted, and a distributed sensor based on synthesized dynamic grating is also presented. Applications in two- or three-dimensional distributed measurements, such as optical tomography of scattering medium, are also reviewed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Novel photonic recursive signal processor with reduced phase-induced intensity noise

    Publication Year: 2006 , Page(s): 2558 - 2563
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (368 KB) |  | HTML iconHTML  

    A new technique to reduce the dominant phase-induced intensity noise (PIIN) in active high-Q recursive photonic signal processors is presented. This is based on using cross-gain-modulation effects in a semiconductor optical amplifier in the recursive loop of the processor. Two different laser sources are used, and no recombination of the optical power from the same laser source occurs in the optical domain, hence, PIIN generation is suppressed. The processor structure also features the advantage that it does not require an incoherent light source. Hence, the free spectral range of the processor is not limited by the coherence of the laser source, as in existing incoherent approaches. Experimental results for the new processor demonstrate a more-than-30-dB reduction in PIIN level for a high-Q bandpass filter, compared to the conventional approach for the same filtering parameters. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On the cascade of incoherent discrete-time microwave photonic filters

    Publication Year: 2006 , Page(s): 2564 - 2578
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1088 KB) |  | HTML iconHTML  

    In this study, a theoretical analysis leading to the derivation of the overall incoherent transfer function of a microwave photonic filter composed of the cascade of two optical structures is developed. Two cases that are more common in practice are considered, i.e., 1) a filter illuminated by a single optical source and 2) a compound filter illuminated by an optical source array. In both cases, the conditions on which the overall incoherent transfer function can be expressed as the product of the individual incoherent transfer functions of each of the optical structures that compose the filter are investigated. In other words, the conditions where the end-to-end electrical linearity is preserved when cascading incoherent optical structures are studied. These results are of importance for the design of complex incoherent filter structures aiming to provide high Q or single resonance performance. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • All-optical signal processing using χ(2) nonlinearities in guided-wave devices

    Publication Year: 2006 , Page(s): 2579 - 2592
    Cited by:  Papers (37)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1256 KB)  

    The authors present a review of all-optical signal-processing technologies based on χ(2) nonlinear interactions in guided-wave devices and their applications for telecommunication. In this study, the main focus is on three-wave interactions in annealed proton-exchanged periodically poled lithium niobate waveguides due to their suitable properties with respect to nonlinear mixing efficiency, propagation loss, and ease of fabrication. These devices allow the implementation of advanced all-optical signal-processing functions for next-generation networks with signal bandwidths beyond 1 THz. In this paper, integrated structures that will allow for improvements of current signal-processing functions as well as the implementation of novel device concepts are also presented. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optical-signal-processing device based on waveguide-type variable delay lines and optical gates

    Publication Year: 2006 , Page(s): 2593 - 2601
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (280 KB) |  | HTML iconHTML  

    In this paper, an optical-signal-processing device mainly designed for time-slot switching is demonstrated. The device is composed of variable delay-line arrays fabricated by planar lightwave circuit technology and high-speed optical gates. The variable delay-line arrays consist of transversal-form or lattice-form optical circuits. The operating principle is based on serial-to-parallel conversion, adjustment of the delay time between the parallel signals, and the gating of the optical bits or packets in the optical region. The device does not require any interaction between lightwaves through optical nonlinear effects or filter banks for code matching. As an example of its operation, label-processing functions are demonstrated, specifically the label swapping of optical return-to-zero pulses. The merits of the proposed device are described and problems that must be solved are also discussed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Interleave filter based on coherent optical transversal filter

    Publication Year: 2006 , Page(s): 2602 - 2617
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (856 KB) |  | HTML iconHTML  

    The principle of the transversal interleave filter previously proposed as a novel class of interleave filter is described. The principle of a conventional 1 × 1 coherent optical transversal filter is reviewed. Then, the fundamental operating principle and the three design conditions required for the novel interleave filter are explained. As examples, three types of filter design, namely 1) a general/transposed design; 2) an asymmetric design; and 3) a symmetric design, are presented, and their interleave filter characteristics are discussed. The designed interleave filters with a free spectral range of 100 GHz was fabricated using silica-based planar lightwave circuit (PLC) technology. The asymmetric design achieved a wide 3-dB passband width of 55 GHz, whereas an ordinary lattice-form interleave filter could not realize a 3-dB passband width larger than 50 GHz because of the halfband property. A small polarization-dependent wavelength shift of 0.01 nm is demonstrated by inserting a single half waveplate in the middle of the circuit. The general/transposed and symmetric designs realized a practical interleave filter with a boxlike transmission spectrum and low chromatic dispersion. The two-stage interleave filter formed by cascading the general and transposed designs has the advantages of a low crosstalk of less than -46 dB and a wide 20-dB stopband width of 40 GHz, whereas the single-stage symmetric design has an extremely small chromatic dispersion of within ±5 ps/nm. In addition, the design concept to realize a 1×N transversal interleave filter is extended. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Design considerations of all-optical A/D conversion: nonlinear fiber-optic Sagnac-loop interferometer-based optical quantizing and coding

    Publication Year: 2006 , Page(s): 2618 - 2628
    Cited by:  Papers (15)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (920 KB)  

    The authors describe in detail the design considerations of our previously proposed novel optical quantizing and coding method for all-optical analog-to-digital (A/D) conversion using nonlinear optical switches based on the Sagnac interferometer. The multiperiod transfer function, which is the key to quantizing and coding, is achieved through a careful design of the Sagnac interferometer. In the experiments, the intensity of the pulse train input to our A/D converter is manually changed, and the corresponding digital signals are successfully mapped generated. Although the input-pulse trains are not the sampling of real analog signal, the principle of our proposed 3-bit A/D conversion at a 10 gigasample per second (Gsps) rate is demonstrated. The proposed optical quantizing and coding, combined with existing optical sampling techniques, will enable ultrafast photonic A/D conversion without electronics. The potential in the frequency regime of over a few hundred gigasamples per second was investigated by using an optical switch that utilizes the optical Kerr effect for fast operation. It was found out that the wavelength allocations and temporal widths of control and probe pulses have to be optimized with respect to the group-velocity dispersion of highly nonlinear fiber. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Spatially resolved detection and equalization of modal dispersion limited multimode fiber links

    Publication Year: 2006 , Page(s): 2629 - 2636
    Cited by:  Papers (10)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (336 KB)  

    The authors present theoretical and experimental results of an optoelectronic-equalization technique that mitigates intersymbol interference caused by differential modal delay in multimode fiber. By exploiting the spatial diversity of the transverse optical-fiber modes, the authors are able to provide a sufficient additional information in the form of mode-dependent photocurrents to enhance total signal integrity. A fabricated two-segment photodetector is demonstrated with a routinely achievable two-times improvement in bandwidth-distance product. They also show the robustness of the technique to the expected variations in graded-index profiles. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analysis and design of active optical filter structures with two-port couplers

    Publication Year: 2006 , Page(s): 2637 - 2648
    Cited by:  Papers (1)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (328 KB) |  | HTML iconHTML  

    A signal processing approach to modeling, analyzing, and synthesizing a particular integrated photonic architecture of optical filters with tunable gains is presented. This particular architecture has two-port couplers and current-controlled semiconductor optical amplifiers (SOAs) fabricated on the same substrate. The device architecture forms a new lattice filter structure. Layer-peeling-type algorithms are developed for the analysis and synthesis of the device. The role of the adjustable gains in a lossless or lossy device is considered, and a novel stability algorithm for the filter structure is presented. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Ultrafast optical signal processing based upon space-time dualities

    Publication Year: 2006 , Page(s): 2649 - 2662
    Cited by:  Papers (19)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (744 KB) |  | HTML iconHTML  

    The last two decades have seen a wealth of optical instrumentation based upon the concepts of space-time duality. A historical overview of how this beautiful framework has been exploited to develop instruments for optical signal processing is presented. The power of this framework is then demonstrated by reviewing four devices in detail based upon space-time dualities that have been experimentally demonstrated: 1) a time-lens timing-jitter compensator for ultralong-haul dense-wavelength-division-multiplexed dispersion-managed soliton transmission, 2) a multiwavelength pulse generator using time-lens compression, 3) a programmable ultrafast optical delay line by use of a time-prism pair, and 4) an enhanced ultrafast optical delay line by use of soliton propagation between a time-prism pair. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Broadband arbitrary waveform generation based on microwave frequency upshifting in optical fibers

    Publication Year: 2006 , Page(s): 2663 - 2675
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (376 KB)  

    An interesting method for broadband arbitrary waveform generation is based on the frequency upshifting of a narrowband microwave signal. In this technique, the original microwave signal is imaged into a temporally compressed replica using a simple and practical fiber-based system. Recently, it has been shown that the conventional limitations of this approach (e.g., bandwidth limitations) can be overcome by exploiting a temporal self-imaging (Talbot) effect in fiber. This effect can be used whenever the signal to be imaged is a quasi-periodic waveform (e.g., microwave tones or any arbitrary periodic waveform). This paper provides a comprehensive study of the microwave frequency upshifting technique with special focus on the Talbot-based approach. Following a theoretical analysis of the design constraints of the conventional approach, the Talbot-based solution is theoretically investigated in detail. In particular, the design specifications of a Talbot-based microwave upshifting system are derived, and the practical capabilities and constraints of these systems (e.g., in terms of achievable bandwidth) are stated and examined. The theoretical findings are confirmed by means of numerical simulations. Moreover, a numerical study of the influence of higher-order (second-order) dispersion terms on system performance is presented, and some additional design rules to minimize the associated detrimental effects are given. The results show that microwave frequencies up to a few hundreds of gigahertz over nanosecond temporal windows can be easily obtained with the described technique using input optical bandwidths in the terahertz range. This has been experimentally confirmed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Photonic RF phase shifter and tunable photonic RF notch filter

    Publication Year: 2006 , Page(s): 2676 - 2682
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (544 KB) |  | HTML iconHTML  

    A new photonic RF phase shifter structure for phased array antennas is presented. It is based on a single dual-output modulator and two optical switches and optical attenuators. This can realize continuous phase shifting of 0°-360° without altering the signal amplitude. It has the advantages of wide bandwidth, fast response time, and fine tuning resolution. Experimental results demonstrate phase shifts over a 360° phase range, with RF signal power changes of less than 0.2 dB, which is in close agreement with predictions. A tunable photonic RF notch filter, which is based on the new phase shifter, is also presented. Experimental results demonstrate continuous tuning of the photonic notch filter over a wide tuning range, which covers the full free spectral range, which is in good agreement with predictions. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optical signal processing via two-photon absorption in a semiconductor microcavity for the next generation of high-speed optical communications network

    Publication Year: 2006 , Page(s): 2683 - 2692
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (456 KB)  

    Due to the introduction of new broadband services, individual line data rates are expected to exceed 100 Gb/s in the near future. To operate at these high speeds, new optical signal processing techniques will have to be developed. This paper will demonstrate that two-photon absorption in a specially designed semiconductor microcavity is an ideal candidate for optical signal processing applications such as autocorrelation, sampling, and demultiplexing in high-speed wavelength-division-multiplexed (WDM) and hybrid WDM/optical time-division-multiplexed networks. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Ultrafast optical distortion equalizer using time-frequency domain processing

    Publication Year: 2006 , Page(s): 2693 - 2700
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (976 KB) |  | HTML iconHTML  

    An ultrafast optical distortion equalizer using time-frequency domain processing that allowed bitwise adaptive compensation of ad hoc optical distortions is described. In the time-frequency domain, because all distortions are distilled to variations in the arrival times of each multiplexed spectral component, they can be treated as one time-frequency distribution. Spatial channels are used to separate spectral components in a distorted bit pulse into plural channels for time-frequency demultiplexing (TF-DEMUX). After TF-DEMUX, temporal and spectral adjustments are achieved through a hard-wired optical delay line for each spatial channel so that each fixed time difference can be canceled. The operation of the proposed ultrafast optical distortion equalizer for uncharacterized optical distortion of chromatic dispersion and timing jitter ranging from several picoseconds to subpicoseconds was demonstrated. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optical frequency combs from semiconductor lasers and applications in ultrawideband signal processing and communications

    Publication Year: 2006 , Page(s): 2701 - 2719
    Cited by:  Papers (55)  |  Patents (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2552 KB)  

    Modelocked semiconductor lasers are used to generate a set of phase-locked optical frequencies on a periodic grid. The periodic and phase coherent nature of the optical frequency combs makes it possible for the realization of high-performance optical and RF arbitrary-waveform synthesis. In addition, the resulting optical frequency components can be used for communication applications relying on direct detection, dense wavelength division multiplexing (WDM), coherent-detection WDM, optical time-division multiplexing, and optical code division multiple access. This paper highlights the recent results in the use of optical frequency combs generated from semiconductors for ultrawideband signal processing and communication applications. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.

Aims & Scope

The Journal of Lightwave Technology contains articles on current research, applications and methods used in lightwave technology and fiber optics.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Peter J. Winzer
Alcatel-Lucent Bell Labs