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1.
《Photonics Technology Letters, IEEE》2009,21(22):1707-1709
2.
Wavelength Remodulation Using DPSK Down-and-Upstream With High Extinction Ratio for 10-Gb/s DWDM-Passive Optical Networks 总被引:1,自引:0,他引:1
We propose and demonstrate a novel wavelength remodulation scheme using differential phase-shift keying (DPSK) modulation format in both downstream and upstream signals for ldquocolorlessrdquo dense wavelength-division-multiplexed (DWDM) passive optical networks (PONs). The scheme enables high extinction ratio in both downstream and upstream remodulated signals. Error-free operation was achieved in a 20-km-reach 10-Gb/s DWDM-PON without dispersion compensation. Timing misalignment tolerance between downstream and upstream remodulated signals and maximum launched optical power for the proposed scheme are studied. Comparison with other wavelength remodulation schemes for DWDM-PONs is also performed, showing the proposed scheme can be a potential candidate for next-generation wavelength reuse DWDM-PONs. 相似文献
3.
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
4.
《Photonics Technology Letters, IEEE》2009,21(1):9-11
5.
《Photonics Technology Letters, IEEE》2009,21(11):715-717
6.
本文提出了一种无源星形波分复用网,网络中任意两个用户都能在1 ̄2跳内通信。本文还提出了波长配置算法,沱能使光器件的调谐范围最小,以降低网络对光器件的要求;它同时还使网络的单跳的比例最大,以降低分组时延。本文还对网络性能进行了理论分析和计算机模拟。 相似文献
7.
Endovitskiy E. O. Kureev A. A. Levitsky I. A. Tutelian S. A. Khorov E. M. 《Journal of Communications Technology and Electronics》2021,66(12):1485-1490
Journal of Communications Technology and Electronics - Non-orthogonal Multiple Access (NOMA) is a technology that can improve the spectral efficiency of Wi-Fi networks in a downlink. NOMA allows... 相似文献
8.
Chih-Lung Tseng Cheng-Kuang Liu Jau-Ji Jou Wei-Yang Lin Chih-Wei Shih Shu-Chuan Lin San-Liang Lee Keiser G. 《Photonics Technology Letters, IEEE》2008,20(10):794-796
We propose and demonstrate the use of fiber ring lasers and Fabry-Perot laser diodes (FP-LDs) for wavelength-division-multiplexing access networks. The fiber ring laser not only generates downstream data traffic but also serves as the wavelength-selecting injection light source for the FP-LD located at the subscriber site. Moreover, it is wavelength tunable and can be applied to dynamic wavelength assignment networks. The ring laser has a tunable range of 30 nm in the C-band and a power fluctuation smaller than 0.6 dB. For 10-Gb/s downstream and 1.25-Gb/s upstream transmissions over 10-km single-mode fiber, power penalties less than 0.9 and 0.5 dB are demonstrated, respectively. A 40-dB sidemode suppression ratio is obtained for the FP-LD injection-locking at 1544.8 nm. 相似文献
9.
Jianjun Yu 《中兴通讯技术(英文版)》2014,(4):40-48
In this paper, we investigate advanced digital signal process ing (DSP) at the transmitter and receiver side for signal pre equalization and postequalization in order to improve spec trum efficiency (SE) and transmission distance in an optical access network. A novel DSP scheme for this optical super Nyquist filtering 9 Quadrature Amplitude Modulation (9 QAM) like signals based on muhimodulus equalization with out post filtering is proposed. This scheme recovers the Ny quist filtered Quadrature PhaseShift Keying (QPSK) signal to a 9QAMlike one. With this technique, SE can be increased to 4 b/s/Hz for QPSK signals. A novel digital superNyquist signal generation scheme is also proposed to further suppress the Nyquist signal bandwidth and reduce channel crosstalk without the need for optical prefiltering. Only optical cou plers are needed for superNyquist wavelengthdivisionmulti plexing (WDM) channel multiplexing. We extend the DSP for shorthaul optical transmission networks by using highorder QAMs. We propose a highspeed Can'ierless Amplitude/Phase 64 QAM (CAP64 QAM) system using directly modulated la ser (DML) based on direct detection and digital equalization. Decisiondirected least mean square is used to equalize the CAP64QAM. Using this scheme, we generate and transmit up to 60 Gbit/s CAP64QAM over 20 km standard single mode fiber based on the DML and direct detection. Finally, several key problems are solved for real time orthogonalfre quencydivisionmultiplexing (OFDM) signal transmission aml processing. With coherent detection, up to 100 Glfit/s 16 QAMOFDM realtime transmission is possible. 相似文献
10.
采用先进的数字信号处理(DSP)技术,在发射机和接收机分别引入预处理和后处理,以提高光接入网络的频谱效率并延长传输距离。研究了一种基于光超奈奎斯特(Super-Nyquist)滤波的类9状态正交振幅调制(9QAM)信号多模均衡(MMEQ)后端DSP算法,使用这种方案,能够有效提高频谱效率,实现了频谱效率高达4 bps/Hz的正交移相键控(QPSK)信号传输;还研究了一种基于数字SuperNyquist信号前端预处理的方案,此方案的优点是不需要光预滤波即可达到相同的频谱效率。使用一个采用直接调制激光器(DML)、直接探测和数字均衡技术的高速无载波幅度相位-64状态正交振幅调制(CAP-64QAM)系统,在20 km标准单模光纤(SSMF)上实现了创纪录的60 Gbit/s CAP-64QAM信号传输;使用相干探测,实现了速率高达100 Gbit/s的64状态正交振幅调制-正交频分复用(16QAM-OFDM)实时传输系统,解决了实时OFDM信号处理中的关键问题。 相似文献
11.
P. Bisaglia L. Sanguinetti M. Morelli N. Benvenuto S. Pupolin 《Wireless Personal Communications》2005,35(1-2):3-18
Time division duplex (TDD) multi carrier-code division multiple access (MC-CDMA) systems have recently been proposed as potential
candidates for next generation (4G) technology. In order to mitigate multiple access interference, in this paper we investigate
pre-equalization schemes for both downlink and uplink transmissions, the former also in a multiple transmit antenna scenario.
In particular, new pre-equalizer techniques are introduced and complexity issues addressed. Numerical results are given to
highlight the effectiveness of the proposed schemes with respect to other existing pre-equalizer solutions.
Paola Bisaglia was born in Padova, Italy, on August 8, 1971. She received the Laurea (cum laude) and Ph.D. degrees in electronic engineering
from the University of Padova, Padova, Italy in 1996 and 2000 respectively.
In 2000 she joined Hewlett-Packard Research Laboratories, Bristol, England, working on Home Phoneline Networking and wireless
LANs.
From 2002 she is a research fellow at the Department of Information Engineering of the University of Padova, Italy. Her research
interests include wireless local area networks; modulation, coding techniques and detection strategies for next generation
(4G) broadband cellular systems, based on the combination of multi-carrier and spread-spectrum modulations.
Luca Sanguinetti is a Ph.D. Student of the University of Pisa. He was born in Empoli, Italy, on February 19, 1977, and he received the Doctor
Engineer degree (cum laude) in information engineering from the University of Pisa, Italy, in 2002. Since 2002 he was with
the Department of Information Engineering of the University of Pisa, where he is working toward the Ph.D. degree in information
engineering under the supervision of Prof. Umberto Mengali and Prof. Michele Morelli. In 2004, he was a visiting Ph.D. student
at the German Aerospace Center (DLR), Oberpfaffenhofen, Germany.
Currently he is involved in a research project dealing with the design and the development of base stations and user terminals
for wideband wireless communications systems able to cope with those reconfigurability and interoperability characteristics
required by the next generation mobile communication systems. His research interests are in wireless communication theory,
with emphasis on synchronization and detection algorithms and channel estimation in multiple-access communication systems.
Michele Morelli received the Laurea (cum laude) in electrical engineering and the “Premio di Laurea SIP” from the University of Pisa, Italy,
in 1991 and 1992 respectively. From 1992 to 1995 he was with the Department of Information Engineering of the University of
Pisa, where he received the Ph.D. degree in electrical engineering. In September 1996 he joined the Centro Studi Metodi e
Dispositivi per Radiotrasmissioni (CSMDR) of the Italian National Research Council (CNR) in Pisa where he held the position
of Research Assistant. Since 2001 he has been with the Department of Information Engineering of the University of Pisa where
he is currently an Associate Professor of Telecommunications. His research interests are in wireless communication theory,
with emphasis on synchronization algorithms and channel estimation in multiple-access communication systems.
Nevio Benvenuto received the Laurea degree from the University of Padova, Padova, Italy, and the Ph.D. degree from the University of Massachusetts,
Amherst, in 1976 and 1983, respectively, both in electrical engineering.
From 1983 to 1985 he was with AT&T Bell Laboratories, Holmdel, NJ, working on signal analysis problems. He spent the next
three years alternating between the University of Padova, where he worked on communication systems research, and Bell Laboratories,
as a Visiting Professor.
From 1987 to 1990, he was a member of the faculty at the University of Ancona. He was a member of the faculty at the University
of L'Aquila from 1994 to 1995. Currently, he is a Professor in the Electrical Engineering Department, University of Padova.
His research interests include voice and data communications, digital radio, and signal processing.
Silvano Pupolin received the Laurea degree in Electronic Engineering from the University of Padova, Italy, in 1970. Since then he joined
the Department of Information Engineering, University of Padova, where currently is Full Professor of Electrical Communications.
He was Chairman of the Faculty of Electronic Engineering from 1990 to 1994, Chairman of the PhD Course in Electronics and
Telecommunications Engineering from 1991 to 1997 and Director of the PhD School in Information Engineering from 2004. Also,
he was member of the programming and development committee from 1997 to 2002 and member of Scientific Committee from 1996
to 2001 of the University of Padova; member of the budget Committee of the Faculty of Engineering from 2003. He has been actively
engaged in research on: Digital communication systems over copper wires and fiber optics; Spread spectrum communication systems;
Design of large reliable communications networks; Effects of phase noise and HPA nonlinearities in OFDM systems; 3G mobile
radio communications systems (UTRA-FDD and TDD) and beyond 3G (OFDM modulation and MC CDMA); Packet radio, Ad-hoc networks
with the use of Bluetooth and WLAN. He was Chairman of the 9-th and 10-th Tyrrhenian International Workshop on Digital Communications
devoted to “Broadband Wireless Communications” and to “Multimedia Communications”, respectively, and he was General Chair
of the 7th International Symposium on Wireless Personal Multimedia Communications (WPMC'04). He spent the summer 1985 at AT&T
Bell Laboratories on leave from Padova, doing research on digital radio systems. He was Principal investigator for research
projects entitled “Variable bit rate mobile radio communication systems for multimedia applications”, “OFDM Systems with Applications
to WLAN Networks”, and “MC-CDMA: an air interface for the 4th generation of wireless systems”. 相似文献
12.
《Photonics Technology Letters, IEEE》2006,18(20):2102-2104
We demonstrated a widely tunable hybrid-integrated external cavity laser on a polymer-based waveguide platform. The lasing wavelength was tuned over 26 nm by locally heating the surface-relief-type polymer waveguide Bragg grating fabricated by using the phase mask. The phase-control heater section was inserted between the laser diode and the Bragg grating for the fine wavelength tuning and the stable single-mode lasing. In the 100-GHz-spaced wavelength-division-multiplexing systems, the 1.25-Gb/s directly modulated data streams at each tuned 32 channel were successfully transmitted. 相似文献
13.
Liu X. Kao Y.-H. Chandrasekhar S. Kang I. Cabot S. Buhl L.L. 《Photonics Technology Letters, IEEE》2007,19(15):1172-1174
We describe a simple method to measure the optical signal-to-noise ratio (OSNR) of on-off-keying (OOK) and differential phase-shift-keying (DPSK) signals by using an optical delay interferometer (ODI) having a sinusoidal and tunable passband. This OSNR monitoring method is independent of chromatic dispersion, polarization-mode dispersion, and noise polarization. We show experimentally that accurate OSNR measurements are made for a 10-Gb/s OOK signal by using a 1-bit ODI and a 40-Gb/s DPSK signal by using a partial-bit ODI with the OSNR ranging from 5 to 25 dB. 相似文献
14.
A signal remodulation scheme of 10-Gb/s differential phase-shift keying(DPSK) downstream and 10-Gb/s on-off keying(OOK) upstream using a semiconductor optical amplifier(SOA) and a Mach-Zehnder intensity modulator(MZ-IM) at the optical networking unit(ONU) side for wavelength division multiplexed passive optical network(WDM PON) is proposed.Simulation results indicate that error-free operation can be achieved in a 20-km transmission,and the receiver sensitivity of return-to-zero differential phase-shift keying(RZ-DPSK) is higher than nonreturn-to-zero differential phase-shift keying(NRZ-DPSK) in the proposed scheme. 相似文献
15.
Han-Shin Jo Cheol Mun June Moon Jong-Gwan Yook 《Wireless Communications, IEEE Transactions on》2009,8(10):4906-4910
This paper proposes two interference mitigation strategies that adjust the maximum transmit power of femtocell users to suppress the cross-tier interference at a macrocell base station (BS). The open-loop and the closed-loop control suppress the cross-tier interference less than a fixed threshold and an adaptive threshold based on the noise and interference (NI) level at the macrocell BS, respectively. Simulation results show that both schemes effectively compensate the uplink throughput degradation of the macrocell BS due to the cross-tier interference and that the closed-loop control provides better femtocell throughput than the open-loop control at a minimal cost of macrocell throughput. 相似文献
16.
17.
A comparative study of DPSK and OOK WDM transmission over transoceanic distances and their performance degradations due to nonlinear phase noise 总被引:1,自引:0,他引:1
Mizuochi T. Ishida K. Kobayashi T. Abe J. Kinjo K. Motoshima K. Kasahara K. 《Lightwave Technology, Journal of》2003,21(9):1933-1943
We have compared experimentally the transmission performance of return-to-zero differential phase-shift keying (RZ-DPSK) with RZ-ON-OFF keying (OOK), nonreturn-to-zero differential phase-shift keying (NRZ-DPSK), and NRZ-OOK for 100/spl times/10-Gb/s transmission with a spectral efficiency of 0.22 b/s/Hz over transoceanic distances. The Q degradation of the RZ-DPSK after transmission over 9180 km was 3 dB greater than that of RZ-OOK. The experimental results clearly showed the major cause of degradation for DPSK is not cross-phase modulation but self-phase modulation. The calculated nonlinear phase noise, i.e., the Gordon-Mollenauer effect, agreed with the experimental results. A distributed-Raman-amplifier assisted erbium-doped-fiber-amplified transmission line acted well in reducing the nonlinear phase noise. 相似文献
18.
《Lightwave Technology, Journal of》2009,27(1):12-18
19.
20.
Calabretta N. Presi M. Proietti R. Contestabile G. Ciaramella E. 《Photonics Technology Letters, IEEE》2007,19(16):1227-1229
We present an innovative architecture to realize a single feeder bidirectional amplified wavelength-division-multiplexing/time-division-multiplexing passive optical network based on modified nonreturn-to-zero differential phase-shift keying (DPSK) downstream signals at 20 Gb/s and a narrowband arrayed waveguide grating (AWG). The AWG plays at the same time the role of channel distributor, simultaneous demodulator for all DPSK channels, and eliminates the need for chromatic dispersion compensation. A saturated semiconductor optical amplifier (SOA) provides bidirectional amplification to compensate the splitter losses. The remodulated upstream signals are obtained at 1 Gb/s by means of a reflective SOA. Experimental results show error-free operation on both downstream and upstream signal. 相似文献