The contribution to the system performance penalty of the ber is much larger than that of the xpm induced timing jitter. The converter operates over a wide range of wave 2004 optical society of america jon 3040 february 2004 vol. We show that experimentally observed spectra can be explained by a simple model that. Optical phase conjugation in fiberoptic transmission systems citation for published version apa. An ultrashort pulse of light, when travelling in a medium, will induce a varying refractive index of the medium due to the optical kerr effect. It has a central core in which the light is guided, embedded in an outer. Volume 82, number 3,4 optics communications 15 april 1991 crossphase modulation between modes of an optical fiber f. Digital compensation of crossphase modulation distortions.
The basic material used in the manufacture of optical. Opc is a promising technology to compensate for determinis. It is shown that an interplay between the effects of groupvelocity dispersion and crossphase modulation can lead to optical wave breaking that manifests as rapid oscillations near the leading or the trailing side. Secondorder theory for selfphase modulation and crossphase. This can be described as a change in the refractive index. Abstract cross phase modulation is often regarded as being threat for optical communication systems. Comparative analysis of self phase modulation spm and cross phase modulation cpm use of optical fiber communication is widely use due to its better bit rate and bandwidth and high carrier frequency with low power consumption. Limitating and beneficial aspects of this fiber nonlinearity on future highbitrate optical communication systems will be discussed, including soliton propagation. Comparative analysis of self phase modulation spm and. Selfphase modulation in optical fibers spie digital library. A limited selection of voltage sources, some of which are highly specialized, can drive eo phase modulators at. It consists of one or more transparent fibers enclosed in a. In particular, xpm causes spectral broadening of signal pulses during raman or parametric optical pulse amplification.
Analysis of spm and fwm in optical fiber communication. Agrawal, modulation instability induced by crossphase modulation, phys. Allen, senior member, ieee abstruct the spectral characteristics of crossphase modu lation xpm in multispan intensitymodulation directdetection. In this paper, we experimentally demonstrate 160 gbs alloptical data modulation with an extinction ratio of 18. Blumenthal, senior member, ieee abstract all optical demultiplexing of 80gbs data to 10 gbs is demonstrated using spectral broadeninginduced by cross phase modulation xpm with subsequent optical bandpass filtering. Optical fiber modulation techniques are therefore required to either encode information or extract information from the fiber guided beam. Crossphase modulation is the change in the optical phase of a light beam caused by the interaction with another beam in a nonlinear medium, specifically a kerr medium.
The first proposed fiber device is an all optical ultrafast 160 gbps reconfigurable xor, or, and, nand, or, nor, not photonic logic gates and the second device is an all optical. These optical xor operation methods successfully achieve alloptical data encryption. Agrawal the institute of optics university of rochester rochester. Thomas, 87060 limoges cedex, france received 26 november 1990 experiments are reported on cross phase modulation. Higherlevel modulation methods reduce the modulation bandwidth and. However, when multiple wavelength division multiplexed wdm channels at narrow channel spacing are used for transmission, cross phase modulation xpm is the dominating transmission impairment. Analytical model and experimental verification of the. In fwm, three signals are combined to form a fourth spurious mixing component results in waste of power from wanted signals to unwanted spurious signals which lead to. Alloptical fiber crossphase modulation wavelength converter the ultrafast wavelength converter, used in each network function, is based on crossphase modulation xpm in optical. Semiconductor optical amplifiers used in cross gain modulation mode xgm, cross phase modulation xpm and four wave mixing fwm mode for wavelength conversions. Depending on the parameter of a light beam which is manipulated, modulators may be categorized into amplitude modulators, phase modulators, polarization modulators etc. Fiberoptic communication systems third edition govind e. Through phase conjugation most of the spm impairments are compensated for. But, it required a large input optical power to saturate the.
Graph for quality factor versus dispersionwith self phase modulation spm and without self phase modulation spm. With the increased transmission distance, a larger number of optical amplifiers have to be used, that generates more optical noise. There are two typical choices for the modulation format of the signal. Crossphase modulation an overview sciencedirect topics. Optical wave breaking and pulse compression due to cross. It consists of a core made up of a dielectric material which is surrounded by a cladding made up of a dielectric material of. Crossphase modulation effects in normal dispersive fibers and their. Roland ryf, in optical fiber telecommunications sixth edition, 20. Index terms crossphase modulation xpm, nonlinear optics, optical fiber communication, raman effect, wavelength conversion. Analytical modeling to evaluate the effect of cross phase modulation. Optical wavelength conversion by crossphase modulation of data. The utilization of xpm allows for an optical event horizon or the generation of an optical refractive index barrier 23. Crossphase modulation in a hydrogenated amorphous silicon. Nonlinear effects in the glass fiber, such as fourwave mixing fwm, selfphase modulation spm, and crossphase modulation xpm would also adversely affect the transmission quality to a significant degree.
Input power propagation distance fiber input variable optic attenuator carrier. Pdf degeneratecrossphase modulation of femtosecond. Degeneratecrossphase modulation of femtosecond laser pulses in a birefringent singlemode optical fiber article pdf available in ieee photonics technology letters 98. Fiber optical communication lecture 5, slide 17 crossphase modulation consider again the case a a expi. Other techniques, including cross polarization modulation 20, cross gain modulation 21, and crossphase modulation 22, have also been studied to achieve optical xor operation. This paper shows the effect of cross phase modulation, a type of nonlinearity found in optical f ibers. We will compare the impact of qfactor, ber and timing jitter. In data transmitters of optical fiber communication systems, phase modulators can be used for encoding the transmitted information. Optical phase conjugation in fiberoptic transmission systems.
Osa analytical description of crossphase modulation in. Wavelength conversion using crossphase modulation xpm in a dispersion. Fourwave mixing fwm and crossphase modulation xpm are the major nonlinear effects that affect the performance of the dense wavelength division multiplexing dwdm system. Optical crosslinks are critical to the development of cubesat swarms high data rate, precision time transfer optical terminal with fsm approach offers a low power, high performance option for optical communications the crosstracmit team is continuing the. Being aware of the sophisticated modulation and detection schemes and algorithms employed in rf engineering, we first want to put the word badvancedused in conjunction with optical modulation formats in proper context. Selfphase modulation spm is due to the power dependence of the refractive index of the fiber core. Their task is to slightly increase and decrease the refractive. These effects are seen from the eye diagrams drawn for the different values ofdispersion. When pulses of different channels are copropagating in a fiber, they undergo. Selfphase modulation spm crossphase modulation xpm fourwave mixing fwm origin of nonlinear e. In this paper, we explore phase modulation in a reversely biased semiconductor machzehnder structure and demonstrate wavelength conversion in a commercial ingaasp machzehnder modulator mzm originally. Optical fiber is a dielectric waveguide and ideally has a cylindrical shape.
For fiber optic communication systems, fiber nonlinearities have long been regarded as being mostly dangerous3. In this paper, we demonstrate optical format and wavelength conversion of 20 and 30 gbs qpsktopam4 by using two nonlinear wave mixing stages 14. The optically modulated onoff keying ook 160 gbs signal is subsequently offcenter filtered and the input carrier is suppressed in order to reduce the. An optical fiber is a cylindrical dielectric waveguide made of lowloss materials such as silica glass. Interference when two or more optical waves are present simultaneously in the same region of space, the total wave function is the sum of the individual wave functions. Advanced optical modulation formats and their comparison. Highspeed optical timedivisionmultiplexedwdm networks. Crossphase modulation can be used as a technique for adding information to a light stream by modifying the phase of a coherent optical beam with another beam through interactions in an appropriate nonlinear medium. Introduction alloptical wavelength conversion is a key technology for improvingtheflexibilityand increasingthecapacityof photonics networks.
Specialty optical fiber is modified, usually by doping, for a specialized function. Intermodal crossphase modulation imxpm has been explored by using. Rp photonics encyclopedia crossphase modulation, xpm. Optical fiber nonlinearity self phase modulation spm single channel effect cross phase modulation xpm multichannel effect cross polarization modulation xpolm multichannel effect 2d constant modulus property is effective to suppress all the above three components. All optical wavelength converters based on cross phase. Crossphase modulation between modes of an optical fiber. Hardeep singh, preeti singh, chetan gupta, effect of cross phase modulation xpm on optical fiber using two wavelength division multiplexed wdm channels,international journal of emerging technologies in computational and applied sciences, marchmay 20. The first step in the design of an optical communication systems is to decide how the electrical signal should be converted into an bit stream. Demonstration of wavelength tunable optical modulation. Spm refers the selfinduced phase shift experienced by an optical field during its propagation through the optical fiber. Rp photonics encyclopedia phase modulators, optical. Osa cross phase modulation squeezing in optical fibers. The nonlinear medium was a single mode fiber and the noise reduction was 3 db. Crossphase modulation mediated pulse control with airy.
Modulation formats optical carrier has the form ete. A novel method of producing squeezed vacuum uses cross phase modulation between a linearly polarized pump signal and the orthogonal polarized vacuum. Selfphase modulation spm is a nonlinear optical effect of lightmatter interaction. The remaining sections are dedicated to other modulation formats, including squarewave phase modulation swm, optical duobinary, and alternate mark inversion ami. The beam may be carried over free space, or propagated through an optical waveguide optical fibre. This technique is applied to fiber optic communications. The phenomenon of cross phase modulation in optical fiber is reported in this paper. Self phase modulation spm cross phase modulation xpm fourwave mixing fwm origin of nonlinear e. The effect of intensity distortion induced by crossphase modulation in dispersive optical fibers is studied.
Find cross phase modulation optical fibers related suppliers, manufacturers, products and specifications on globalspec a trusted source of cross phase modulation optical fibers information. When a probe pulse copropagqtes with a pump pulse inside an optical fiber, the two can interact through crossphase modulation. Conclusion the effect of self phase modulation on optical fiber is reported in this paper. We have shown by simulation in the case of nrz transmission, the qfactor, jitter, ber, and eye opening for different length of fiber. Optical fiber modulation techniques for single mode fiber. This variation in refractive index will produce a phase shift in the pulse, leading to a change of the pulses frequency spectrum. In that case, the phase modulation often needs to be strong in order to obtain a large number of optical sidebands. Therefore, it is important to know what happens when the light signal propagates in the fiber and how to. All optical demultiplexing using fiber cross phase modulation xpm and optical filtering bengterik olsson and daniel j. Proposed approach for driving eo phase modulators electrooptic eo phase modulators, such as the fibercoupled version in figure 1, are frequently driven at rates of 1 ghz or higher. Crossphase modulation xpm is a nonlinear optical effect where one wavelength of light can affect the phase of another wavelength of light through the optical. Chapter secure communication in fiberoptic networks 11. It is shown that, in most configurations in which distortions that are due to crossphase modulation can become significant to optical communications, the effect of crossphase modulation can be described with excellent accuracy by simple analytical expressions. Nonlinearitytolerant modulation formats for coherent.
Here we report on such cross phase modulation using 1nj 150fs pulses from a low noise stretched pulse laser. The intrachannel nonlinear distortions are removed by intrachannel digital. Pdf experimental study of crossphase modulation reduction in. We have studied xpm experimentally in the fiber raman amplification soliton laser. Regenerative properties of the wavelength converter are demon strated, and the effect of. An optical modulator is a device which is used to modulate a beam of light. Wavelength conversion based on crossphase modulation in a. Modulation in multispan wdm optical fiber systems rongqing hui, senior member, ieee, kenneth r. In this paper, we focus on how advanced optical modulation formats enable highcapacity optically routed transport networks. It is a receiverside scheme that uses a harddecision unit to estimate data for the calculation of xpm fields using the perturbation technique. The second is nonlinear optical interaction due to cross and selfphase modulation between the complexvalued temporal amplitude profile of pump pulses and the amplitude profiles of generated signal and idler pulses in optical fiber photonpair sources utilizing the fourwave mixing process named modulation instability. Snigdharaj mishra, in undersea fiber communication systems second edition, 2016. Dispersion management is especially important in this respect. Basic structure of an optical fiber an optical fiber is a flexible, transparent fiber made by glass silica or plastic to a diameter slightly thicker than that of a human hair.
Regenerative 80gbs fiber xpm wavelength converter using. Measurands then induce a change in the optical phase, frequency or polarization state of the beam. When pulse pairs copropagate in a fiber, each pulse chirps the other through crossphase modulation xpm. The interaction regimes due to xpm of two pulses and their dynamics have been studied in 22.
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