共查询到20条相似文献,搜索用时 15 毫秒
1.
The performance of plastic optical fiber is greatly influenced by the related but distinct effects of mode coupling and differential modal attenuation (DMA). We establish a method for estimating the matrix that governs both of these effects and allows us to distinguish the two. We obtain partial quantitative estimates of this matrix for a particular graded-index plastic optical fiber (GI-POF). The sample we studied exhibited strong but incomplete mode coupling over 100-m lengths, while DMA was largely limited to a centerline defect. We show that much of the loss of the fiber can be attributed to mode coupling between mode groups with similar effective indexes. 相似文献
2.
《Lightwave Technology, Journal of》2009,27(3):253-265
3.
《Photonics Technology Letters, IEEE》2008,20(19):1642-1644
4.
We propose and experimentally demonstrate an all-optical phase multiplexing scheme using four-wave mixing in a highly nonlinear fiber. Two 10-Gb/s pi/2-shifted return-to-zero (RZ) differential phase-shift-keying (DPSK) wavelength-division-multiplexing (WDM) signals are successfully phase-multiplexed into a 20-Gb/s RZ differential quadrature phase-shift-keying signal with a negative 1.6-dB power penalty. With more input DPSK WDM signals, the proposed scheme can be applied to obtain a multilevel phase-shift-keying signal with increased capacity and enhanced spectral efficiency. 相似文献
5.
Chongjin Xie Inuk Kang Gnauck A.H. Moller L. Mollenauer L.F. Grant A.R. 《Lightwave Technology, Journal of》2004,22(3):806-812
We investigate using alternate-polarization (APol) on-off keying formats, in which adjacent bits have orthogonal states of polarization, to suppress intrachannel nonlinear impairments in dispersion-managed (DM) optical fiber transmission systems. Simple methods to generate the APol formats are discussed, and the transmission performance of the APol formats for both 40-Gb/s DM systems and 10-Gb/s DM-soliton systems is experimentally studied. We show that the APol formats can significantly improve the performance of 40-Gb/s DM transmission systems, while the improvement of 10-Gb/s systems is smaller. 相似文献
6.
《Advanced Packaging, IEEE Transactions on》2009,32(3):644-649
7.
Optimized are the label extinction ratio and dispersion compensation of an optical label switching transmission system, which employs 40-Gb/s return to zero differential phase shift keying(RZ-DPSK) payload labeled with 622-Mb/s amplitude shift keying(ASK) control data. In our scheme, the receiver sensitivities of payload and label achieves -27.8 dBm and -33.5 dBm, respectively. After transmitted over 40 km, 60 km and 80 km single mode fiber(SMF)(with dispersion compensation) respectively, the payload can be recovered with no power penalty, while the label can be recovered with less than 2 dB penalty. 相似文献
8.
We report that the center-launching technique can be improved to selectively excite the fundamental mode of multimode fiber (MMF). This ldquomode-field matchedrdquo center-launching technique enables us to excite only the fundamental mode in the MMF and, consequently, avoid the inherent limitations imposed by the differential mode delay. We realize this mode-field matched center-launching technique simply by fusion-splicing a single-mode fiber (SMF) pigtailed transmitter to the MMF. The splicing condition is optimized to expand the core of SMF slightly so that it can match the mode field distribution of the fundamental mode of MMF. The results show that, by using this launching technique, we can achieve the transmission characteristics similar to SMF and drastically increase the bandwidth-distance product of MMF. For demonstrations, we have successfully transmitted 10- and 40-Gb/s signals over 12.2 and 3.7 km of MMF, respectively, without using any dispersion compensation techniques. We have also evaluated the robustness of the MMF link implemented by using the proposed launching technique against the mechanical perturbations such as the lateral offset between fiber connectors, fiber bending, and fiber shaking. 相似文献
9.
Polarization mode dispersion (PMD) is caused by noncircular fiber cores and poses a serious threat for transmitting 10-Gb/s optical signals over older fibers and 40-Gb/s optical signals over any type of fiber. We study the architecture of a PMD compensator (PMDC) capable of 40-Gb/s operation in X-cut Y-propagation lithium niobate (LiNbO3) based on cascaded integrated optical TE-TM mode converters with endlessly adjustable coupling phases and propose several improvements in its architecture to tailor its performance toward highest bit rates. The performance of such distributed PMDCs can be pushed toward highest bit rates of 160 and 640 Gb/s if they are implemented in mixed ferroelectric crystals such as lithium niobate tantalate (LiNb1-y/Tay/O3) or lithium tantalate (LiTaO3) crystals, respectively. A tantalum (Ta) content y of up to 0.5 is good to realize a distributed PMDC for about 160-Gb/s operation. Two- and three-phase TE-TM mode converters for integrated optical PMD compensation are compared, and the latter are found to have slightly better electrooptic efficiency. For Z-cut lithium tantalate, four-phase electrodes which need only two independent operation voltages are found to be more attractive. 相似文献
10.
A 40-Gb/s wavelength converter based on cross-phase modulation in a dispersion-shifted fiber has been investigated through pulse measurements and simulation. The most important parameter is the dispersive walkoff, which makes the required input power wavelength dependent and determines the optical bandwidth. Simulations show the feasibility of the 160-Gb/s operation by using 2-ps pulses and a highly nonlinear dispersion-shifted fiber 相似文献
11.
This paper proposes to combine prechirping with dispersion management scheme in such a way as to suppress the power penalty induced by self-phase modulation (SPM) and cross-phase modulation (XPM) in 40-Gb/s per channel wavelength-division multiplexed (WDM) transmission systems with long-amplifier spacing. First, we show that the optimum total dispersion to minimize SPM depends on prechirping and the local dispersion of the transmission fiber, unlike that for minimizing XPM. Next, it is shown that, by optimizing the combination of prechirping and local dispersion, these two optima can be made to match so as to improve the allowable maximum fiber input power. Finally, the operation of the proposed optimization scheme is confirmed experimentally, and 4×40-Gb/s WDM transmission over 400 km of nonzero dispersion-shifted fiber (NZDSF) is demonstrated successfully with the fiber input power of +10 dBm/ch and 250 GHz channel spacing 相似文献
12.
We evaluate the system power penalty for different modulation formats-nonreturn-to-zero (NRZ), return-to-zero (RZ), dispersion-managed solitons, and prechirped RZ-in the presence of polarization mode dispersion (PMD) for 10-Gb/s terrestrial systems. All orders of PMD are considered by simulating the fiber using the coarse-step method, and a statistical approach is used to estimate the occasional fading of the signals. We show that pulses with lower duty-cycles perform better in general, and the system performance is improved if appropriate prechirping interacts with the residual chromatic dispersion of the fiber 相似文献
13.
《Optical Fiber Technology》2014,20(5):461-466
We present a method for transmitting 25-Gb/s optical nonreturn-to-zero signals at a wavelength of 1550 nm over a 40-km single-mode fiber without any dispersion compensation methods. We propose optimized self-phase modulation by varying parameters of the fiber launching power and the extinction ratio of optical non-return to zero signals to overcome severe signal distortions by the chromatic dispersion effect. Using the optimization of the self-phase modulation effect, we were able to transmit 25-Gb/s optical nonreturn-to-zero signals over a 40-km single-mode fiber, which can be applicable to passive optical networks with a single wavelength channel and a high split ratio. We demonstrated that the self-phase modulation effect can be controlled by the extinction ratio and the fiber launching power. 相似文献
14.
Xuetian Huang Lei Zhang Min Zhang Peida Ye 《Photonics Technology Letters, IEEE》2005,17(7):1423-1425
The performance degradation of differential quadrature phase-shift keying (DQPSK) wavelength-division-multiplexed (WDM) systems due to self-phase modulation (SPM)- and cross-phase modulation (XPM)-induced nonlinear phase noise is evaluated in this letter. The XPM-induced nonlinear phase noise is approximated as Gaussian distribution and summed together with the SPM-induced nonlinear phase noise. We demonstrate that 10-Gb/s systems, whose walkoff length is larger than 40-Gb/s systems', are more sensitive to XPM-induced nonlinear phase noise than 40-Gb/s systems. Furthermore, DQPSK WDM systems show lower tolerance to both SPM- and XPM-induced nonlinear phase noise than differential phase-shift keying WDM systems. 相似文献
15.
Pincemin E. Tan A. Tonello A. Wabnitz S. Ania-Castanon J.D. Mezentsev V. Turitsyn S.K. Jaouen Y. Gruner-Nielsen L. 《Photonics Technology Letters, IEEE》2007,19(20):1613-1615
We experimentally compare the performance of standard single-mode fiber (SSMF) and UltraWave fiber (UWF) for ultra-long-haul (ULH) 40-Gb/s wavelength-division-multiplexing transmissions. We used the carrier-suppressed return-to-zero amplitude-shift-keying (CSRZ-ASK) and the carrier-suppressed return-to-zero differential-phase-shift-keying (CSRZ-DPSK) formats, which are particularly well-adapted to 40-Gb/s pulse-overlapped propagation. We demonstrate that transmission distance well beyond 2000 km can be reached on UWF with both the CSRZ-ASK and CSRZ-DPSK formats, or on SSMF with the CSRZ-DPSK format only, thus indicating that SSMF-based infrastructure of incumbent carriers can be upgraded at 40-Gb/s channel rates to ULH distances. 相似文献
16.
We compare nonreturn-to-zero (NRZ) with return-to-zero (RZ) modulation format for wavelength-division-multiplexed systems operating at data rates up to 40 Gb/s. We find that in 10-40-Gb/s dispersion-managed systems (single-mode fiber alternating with dispersion compensating fiber), NRZ is more adversely affected by nonlinearities, whereas RZ is more affected by dispersion. In this dispersion map, 10- and 20-Gb/s systems operate better using RZ modulation format because nonlinearity dominates. However, 40-Gb/s systems favor the usage of NRZ because dispersion becomes the key limiting factor at 40 Gb/s 相似文献
17.
Baeyens Y. Weimann N. Roux P. Leven A. Houtsma V. Kopf R.F. Yang Yang Frackoviak J. Tate A. Weiner J.S. Paschke P. Young-Kai Chen 《Solid-State Circuits, IEEE Journal of》2004,39(10):1697-1705
High-performance and compact 40-Gb/s driver amplifiers were realized in 1.2-/spl mu/m emitter double-heterojunction InGaAs-InP HBT (D-HBT) technology with a maximum cut-off frequency (f/sub T/) of 150 GHz and a maximum oscillation frequency (f/sub max/) of 200 GHz. Two-stage differential drivers feature a lumped input and fully distributed output stage and deliver a maximum differential output swing of 11.3 V peak-to-peak (V/sub pp/) at 40 Gb/s with less then 350 fs of added rms jitter and rise and fall times of about 7 ps while consuming a total power of 3 W. When biased at a lower output swing of 6.3 V/sub pp/, excellent 40-Gb/s eyes with a 7-ps fall time, 6-ps rise time, and no observable jitter deterioration compared with the input source are obtained at a reduced power consumption of 1.7 W. On-wafer measured differential S-parameters show a differential gain of 25 dB, 50 GHz bandwidth, and input and output reflection below -20 dB from 2 to 45 GHz. The amplifiers' small die size (1.0/spl times/1.7 mm), relatively low power consumption, large output swing, and ability to have dc coupled inputs and outputs enable compact 40-Gb/s optical transmitters with good eye opening for both conventional transmission formats such as nonreturn-to-zero and return-to-zero and alternative formats such as duobinary and differential phase shift keying. 相似文献
18.
Bidirectional ROF Links Using Optically Up-Converted DPSK for Downstream and Remodulated OOK for Upstream 总被引:1,自引:0,他引:1
We propose a novel radio-over-fiber system to provide full-duplex services by using optical differential phase-shift keying modulation format at the central station for downstream and on-off keying remodulation of the downlink carrier at the base station (BS) for upstream. The optical carrier suppression modulation scheme is employed to simultaneously generate and up-convert 40-GHz optical millimeter wave. As the same optical carrier is used for both uplink and downlink, no additional light source is required at the BS, which greatly reduces the cost and simplifies the overall system. Simulations and experimental results show that the bidirectional 2.5-Gb/s data is successfully transmitted over 40-km single-mode fiber (SMF-28) with less than 2-dB power penalty 相似文献
19.
Breuer D. Ehrke H.J. Kuppers F. Ludwig R. Petermann K. Weber H.G. Weich K. 《Photonics Technology Letters, IEEE》1998,10(6):822-824
We investigate experimentally and theoretically the effect of signal power and dispersion compensation scheme in unrepeated return-to-zero single-channel 40-Gb/s 150-km transmission using standard single-mode fiber (SMF), nonzero dispersion shifted fiber [true wave fiber (TWF)] and dispersion shifted fiber (DSF). It is shown, that standard SMF allows significantly higher fiber-input power than nonzero dispersion shifted fiber or dispersion shifted fiber and, therefore, offers larger transmission spans 相似文献
20.
《Photonics Technology Letters, IEEE》2009,21(4):191-193