We extend the well-known analogy between problems of paraxial diffraction in space and dispersion time to optical pulse compression propose a time-domain analog spatial imaging that allows for distortionless expansion or power waveforms. call this new concept temporal derive equivalent expressions focal length f-number lens magnification an system. It should now become possible, with microscope, expand ultrafast phenomena scale is accessible conventional high-speed photodiodes.

The improved performance of an optical time-domain reflectometer (OTDR) through the application a correlation technique using codes with complementary autocorrelation properties is discussed. theoretical foundations method are presented along experimental results exhibiting best one-way range reported to date for practical long-haul, long-wavelength OTDR system.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

The theory of canonical transforms is applied to establish the mathematical foundations operator algebra method, leading useful relations between geometrical ray optics and representation wave optics. transfer a general first-order system expressed in terms elements ray-transfer ABCD matrix. exemplified through discussion basic subgroups special types systems: Fourier, Fresnel, imaging, afocal.

We develop an analytic model of Coherent Optical Orthogonal Frequency Division Multiplexing (OFDM) propagation and detection over multi-span long-haul fiber links, comprehensively rigorously analyzing the impairments due combined effects FWM, Dispersion ASE noise. Consistent with prior work Innoe Schadt in WDM context, our new closed-form expressions for total FWM received power fluctuations wake dispersive phase mismatch OFDM transmission, indicate that contributions multitude spans...

Fresnel diffraction is described by replacing the Fresnel-Kirchhoff integral, lens transfer factor, and other operations operators. The resulting operator algebra leads to description of Fourier optics in a simple compact way, bypassing cumbersome integral calculus. Aberration effects Gaussian beam illumination are also treated as extension present theory.

Recent advances in electronic linearization of AM CATV transmitters based on externally modulated diode pumped Nd:YAG lasers are presented. The theoretical principles and practical issues related to the methods feedforward predistortion linearization, factors affecting system performance emerging devices, circuits, subsystems, systems architectures reviewed. In experiments a linearized system, transmission over two fibers 30 km each, wherein each fiber carries 80 NTSC channels, is now...

A general rigorous theory of optical heterodyne and homodyne measurements is presented. The power spectrum the photocurrent resulting from two uncorrelated beams mixing on a photodetector derived. In particular, analysis presented for delayed self-homodyne method which used to characterize laser source linewidth by Mach-Zehnder interferometer with delay exceeding coherence length. Existing treatments are generalized address non-Lorentzian sources arbitrary lineshape. further cover case...

The sixth generation (6G) of mobile networks will radically change the way that we interact, as artificial intelligence (AI)-enabled fixed and wireless communications infrastructure offer improved performance an unprecedented variety applications. 6G builds upon evolution 5G, which already introduces various innovations in network architecture, technologies, operation capabilities. We expect further progress across many areas, including evolving Internet Protocol/optical transport (called...

A long-coherence-length, diode-pumped, monolithic Nd:YAG laser operating at 1.32 mu m is used to perform coherent FMCW (frequency-modulated continuous wave) reflectometry measurements. Compared with semiconductor-based lasers, the low phase noise of source offers greatly increased distance range combined sensitivity optical reflections. Measurement Rayleigh backscatter from 50 km fiber demonstrated over 60 dB two-way dynamic range. Two-point spatial resolution be better than 10 cm. This and...

Spectral processor based on arrayed waveguide grating and free-space manipulation is capable of arbitrary filtering at record metrics 0.8GHz resolution over 200GHz span. Narrowband coherent drop-demultiplexing controlled optical shaping demonstrated in unison with digital sub-banding.

Humankind has entered a new era wherein main characteristic is the convergence of various technologies providing services and exerting major impact upon all aspects human activity, be it social interactions with natural environment. Fixed networks are about to play role in this convergence, since they form, along mobile networks, backbone that provides access broad gamut services, accessible from any point globe. It for reason we introduce forward-looking approach fixed particularly focused...

A wideband, low drive voltage LiNbO3 electro-optic modulator is demonstrated utilising electrodes patterned according to a 13-bit Barker sequence. It exhibits 3.5 dB optical insertion loss and 7.5 V switching voltage. The modulation frequency response remains ≥ −5 (optical) beyond 40 GHz.

Single-mode operation of a monolithic semiconductor-laser-pumped unidirectional ring Nd:YAG laser has been demonstrated at 1319 and 1338 nm. The design optimizes the polarization eigenvalue difference between counterpropagating modes ring. threshold is 4.5 mW, magnetic-field requirement for approximately 100 G.

The canonical operator theory introduced recently for the description of lossless first-order optics is extended here to systems with loss or gain, elucidating relation between and complex ray methods. spread functions in space, frequency, hybrid domains are derived terms ABCD ray-transfer matrix as well four other new descriptions geometrical optics. fourfold correspondence among these matrices, Hamilton characteristics, leads derivation fundamental explicit representations transfer their...

We introduce an efficient and accurate nonlinear compensator (NLC) for digital back-propagation (DBP) of coherent optical OFDM receivers, based on a factorization procedure the Volterra Series Transfer Function (VSTF) with 3N degrees freedom N frequency samples. The O(N2) compensation complexity generic evaluation (normalized per-subcarrier) is reduced to 28 + 6logN. Our analysis simulations indicate that this NLC system outperforms previous VSTF-based non-linear methods. Compared most...

We propose a new way to structure the digital signal processing for reduced guard-interval (RGI) OFDM optical receivers. The idea is digitally parallelize over multiple parallel virtual sub-channels, occupying disjoint spectral sub-bands. This concept well known in or analog sub-carrier domains, but it turns out that can also be performed efficiently domain. Here we apply critically sampled uniform analysis and synthesis DFT filter bank techniques order realize novel hardware efficient...

The optical orthogonal frequency-division multiplexing transmitter typically employs a quadrature modulator (QM) to achieve up-conversion for high-capacity long-haul transmission. Bias tracking of the QM is essential minimize impairments and maintain long-term stable operation. A dither-free bias control circuit proposed optimum points QM. By monitoring output power P <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">o</sub> , can be acquired...

Next upgrade to QAM256 poses formidable barriers in terms of attainable performance and energy-efficiency DAC driver + MZM based Transmitters (Tx). A promising alternative, potentially changing the ‘rules game’ is optical DACs (oDAC). In previous work, we proposed a PAM4-driven Tx generating up 256QAM. Here introduce novel oDAC parallelizing pair optimized 2-segment MZMs, remarkably fed by 4 uncoupled NRZ signals. Based on IQ-nested new oDACs, resulting DAC-less QAM 8 drivers. The energy...

An LiNbO3 travelling-wave optical modulator at 1.3μm wavelength with an aperiodic {+ + - +} Barker code phase-reversal electrode pattern is demonstrated. insertion loss of 3.3 dB, half-wave drive voltage 11 V and a photodetector-limited bandwidth in excess 20 GHz are achieved.

Mode propagation through first-order systems with loss or gain is derived based on a canonical transform theory developed recently. In analogy to quantum theory, creation and annihilation operators are defined for the construction of high-order modes. The evolution these mode-generation an optical system shown describe actual fields that parameterized by two raylike labels—two guiding rays. mode-generating create set generalized modes may be reduced ordinary Her-mite–Gaussian only in...

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> We revisit the treatment of laser phase noise, with particular application to coherent and differential phase-shift keyed (PSK) systems, developing a considerably simplified yet very accurate analysis based on <emphasis emphasistype="boldital">phase-noise exponent commutation</emphasis> (PNEC) premise that receive filtering may be effectively applied in polar (angular) domain treating for first...

We extend the Golay coded Optical Time Domain Reflectometry OTDR technique for first time from direct-detection to coherent OTDR, investigating unique issues arising in setting regarding signal processing operations and efficient real-time implementation of DSP practical receivers resulting performance. also derive detailed flow block diagrams OTDRs use an intuitive analogy between spatial speckle temporal fading noise guide selection system parameters. present extensive simulations...

Subbanded digital signal processing (DSP) with underdecimated (Udeci) filter banks (FBs), is a recent DSP technique whereby the optical channel bandwidth digitally sliced into multiple spectrally disjoint subbands (SBs) to be processed in parallel. In terms of hardware (HW) architecture, subbanding amounts an alternative mode parallelizing receiver task slower processors, parallelization performed frequency domain (FD) rather than time (TD). We show that FD especially suited long-haul fiber...