共查询到20条相似文献,搜索用时 31 毫秒
1.
《Photonics Technology Letters, IEEE》2009,21(5):322-324
2.
《Photonics Technology Letters, IEEE》2008,20(24):2051-2053
3.
《Solid-State Circuits, IEEE Journal of》2008,43(8):1763-1771
4.
We experimentally investigated optical noise tolerance of a polarization-, wavelength-, and filter-free all-optical clock recovery system based on a monolithic mode-locked laser diode. The results showed that for input signal degradation, the jitter of the recovered clock did not degrade to approximately 8 dB/nm of the optical SNR. We also compared the clock recovery performance as functions of the wavelength and the modulation format (on-off keying and phase-shift keying) of the input data signals. We revealed that no significant changes were measured in the clock recovery performance despite such changes in the parameters of the input data signals, indicating that noise-tolerable clock recovery is expected, retaining the polarization- and the filter-free operations, regardless of the wavelength and the modulation format of the input data signals, by using our new scheme. 相似文献
5.
恶化非归零码信号的全光时钟恢复 总被引:3,自引:0,他引:3
全光时钟提取结构应对输入信号的恶化程度有一定的容忍度.在一种半导体光放大器(SOA) 啁啾光纤布拉格光栅(CFBG) 受激布里渊散射(SBS)的方式实现非归零(NRZ)码信号的全光时钟提取结构中,半导体光放大器和啁啾光纤布拉格光栅共同作用实现了非归零码信号的时钟分量增强,基于受激布里渊散射的全光时钟提取结构提取出非归零码的光时钟信号.实验通过对不同恶化程度的非归零码信号的时钟提取比较发现,恶化信号的信噪比是影响光时钟提取的关键.输入非归零码信号的信噪比越差,光时钟信号光谱的噪声水平越高,提取出的光时钟信号的幅度越低.当时钟增强非归零码信号的时钟数据抑制比低于-10 dB时,无法实现非归零码信号的时钟提取. 相似文献
6.
All-Optical Clock Recovery Using Erbium-Doped Fiber Laser Incorporating an Electroabsorption Modulator and a Linear Optical Amplifier 总被引:1,自引:0,他引:1
Lui L. F. K. Xu L. Lee C. C. Wai P. K. A. Tam H. Y. Lu C. 《Photonics Technology Letters, IEEE》2007,19(10):720-722
We demonstrated a 10-GHz all-optical clock recovery system using an erbium-doped fiber laser that incorporates an electroabsorption modulator and a linear optical amplifier. Stable pulses with peak power of 200 mW and pulsewidth of 6 ps are obtained. The output power and the pulsewidth of the recovered clock pulses are independent of the input data pattern. Stable optical clock can still be observed when the input data rate varies by more than 60% of the fundamental frequency without any optical tunable delay line inside the laser cavity. The scheme is essentially wavelength transparent for the whole C-band which recovers clock pulses from input data wavelength between 1525 and 1565 nm 相似文献
7.
《IEEE transactions on circuits and systems. I, Regular papers》2009,56(2):384-394
8.
In this paper, we design high-speed optical fiber networks based on the time-division multiple-access (TDMA) technique. To achieve an ultrahigh throughput, optical signal processing should be used in the network. We present a feasible scheme to implement optical TDMA networks, with the emphasis on optical clock distribution, synchronization, and optical time demultiplexing. Since the proposed network uses two wavelengths to carry optical TDMA and clock signals respectively, at each TDMA receiver slot synchronization is feasibly achieved by using simple optical delay lines to process the separated optical clock and TDMA signals. This in turn allows us to build a large-scale distribution network which is attractive for future HDTV broadcasting applications. Using the proposed scheme also allows to implement a high-capacity broadcast and select optical TDMA network for real-time data communications. 相似文献
9.
《Lightwave Technology, Journal of》2009,27(16):3531-3539
10.
Minhui Yan Chih-Hung Chen Wei-Ping Huang 《Lightwave Technology, Journal of》2008,26(12):1569-1576
A novel clock recovery scheme utilizing the relaxation oscillation in a directly modulated laser (DML) for burst-mode transmission is proposed for the first time. In this scheme, the DML generates the clock tone along with the transmitted non-return-to-zero data in the optical signal. An injection-locked oscillator (ILO) is employed in the receiver to extract the clock tone and restore the clock. The proposed scheme is investigated systematically and verified by simulations with different laser modulation currents as well as some nonideal characteristics of the system. The simulation results show that the low cost clock recovery method using an ILO in an optical link using a regular DML is highly efficient for burst-mode transmission at 10 Gbps. 相似文献
11.
Min Yong Jeon Young Ahn Leem Dong Churl Kim Eundeok Sim Sung‐Bock Kim Hyunsung Ko Dae‐Su Yee Kyung Hyun Park 《ETRI Journal》2007,29(5):633-640
We report an experimental demonstration of 40 Gbps all‐optical 3R regeneration with all‐optical clock recovery based on InP semiconductor devices. We also obtain all optical non‐return‐to‐zero to return‐to‐zero (NRZ‐to‐RZ) format conversion using the recovered clock signal at 10 Gbps and 40 Gbps. It leads to a good performance using a Mach‐Zehnder interferometric wavelength converter and a self‐pulsating laser diode (LD). The self‐pulsating LD serves a recovered clock, which has an rms timing jitter as low as sub‐picosecond. In the case of 3R regeneration of RZ data, we achieve a 1.0 dB power penalty at 10?9 BER after demultiplexing 40 Gbps to 10 Gbps with an eletro‐absorption modulator. The regenerated 3R data shows stable error‐free operation with no BER floor for all channels. The combination of these functional devices provides all‐optical 3R regeneration with NRZ‐to‐RZ conversion. 相似文献
12.
《Optical Fiber Technology》2006,12(1):59-70
For optical clock recovery of nonreturn-to-zero (NRZ) signals of more than 40 Gb/s, we propose and experimentally demonstrate a simple clock recovery scheme through beating process between the carrier frequency component and one of the clock frequency components in modulated NRZ signals. The proposed scheme consists of a circulator, a variable optical attenuator (VOA), and two fiber Bragg grating (FBG) filters. With FBG filters and a VOA, the proposed scheme can equalize the amplitudes of two extracted frequency components for a maximum clock-to-noise ratio (CNR). Through this scheme, we have squared the adjustment range of the VOA and achieved an enhanced CNR of more than 15 dB before the receiver in experiment. Bit error rate (BER) curves for back-to-back and 80 km transmissions showed that BERs of less than 10−11 can be obtained without error floors for both cases. We expect that the proposed scheme can operate as an efficient clock extraction system for high-speed optical communications. 相似文献
13.
《Electron Devices, IEEE Transactions on》2008,55(12):3367-3374
14.
This paper presents a delay‐locked‐loop–based clock and data recovery (CDR) circuit design with a nB(n+2)B data formatting scheme for a high‐speed serial display interface. The nB(n+2)B data is formatted by inserting a ‘01’ clock information pattern in every piece of N‐bit data. The proposed CDR recovers clock and data in 1:10 demultiplexed form without an external reference clock. To validate the feasibility of the scheme, a 1.7‐Gbps CDR based on the proposed scheme is designed, simulated, and fabricated. Input data patterns were formatted as 10B12B for a high‐performance display interface. The proposed CDR consumes approximately 8 mA under a 3.3‐V power supply using a 0.35‐μm CMOS process and the measured peak‐to‐peak jitter of the recovered clock is 44 ps. 相似文献
15.
《Circuits and Systems II: Express Briefs, IEEE Transactions on》2009,56(3):190-194
16.
《Photonics Technology Letters, IEEE》2009,21(6):377-379
17.
《Lightwave Technology, Journal of》2009,27(20):4390-4393
18.
采用两个级联外部调制器产生四倍频光载毫米波的光纤无线通信系统 总被引:4,自引:1,他引:3
研究了一种采用两个级联外部调制器基于光载波抑制原理产生四倍频毫米波的光纤无线通信(ROF)系统.在中心站利用电混频器产生副载波复用信号,通过第一个外部调制器产生两倍射频(RF)信号的光载毫米波信号,再通过第二个外部调制器产生四倍射频信号的光载毫米波.实验显示采用频率为10 GHz的射频信号源和2.5 Gbit/s的数据基带信号混频通过两个级联外部凋制器后产生毫米波的频率为40 GHz,并且在单模光纤中传输距离达20 km,功率代价小于2 dB. 相似文献
19.
Bit rate and wavelength transparent all-optical clock recovery scheme for NRZ-coded PRBS signals 总被引:1,自引:0,他引:1
J. Slovak C. Bornholdt J. Kreissl S. Bauer M. Biletzke M. Schlak B. Sartorius 《Photonics Technology Letters, IEEE》2006,18(7):844-846
All-optical clock recovery from 40-Gb/s nonreturn-to-zero (NRZ) pseudorandom binary sequence data streams based on self-pulsating lasers is presented. A compact preprocessing circuit is utilized to convert an NRZ signal to a pseudoreturn-to-zero sequence before injecting into the optical clock. It comprises a semiconductor optical amplifier followed by a periodical wavelength-division-multiplexing demultiplexer filter. A stable sinusoidal clock signal with a root-mean-square jitter below 700 fs is detected at the output of the self-pulsating laser within data dynamic range of more than 8 dB. The performance of the all-optical clock recovery scheme is investigated by varying the bit rates between 39.81 and 43.02 Gb/s as well as for various wavelengths in the C-band. 相似文献
20.
Yanhua Deng Kravtsov K. Fok M.P. Prucnal P.R. Sasaki K. Gupta G.C. Kobayashi S. 《Lightwave Technology, Journal of》2009,27(23):5370-5375
In this paper, we investigate all-optical truly asynchronous detection without global clocking in an incoherent optical code-division multiple-access (CDMA) system. The implemented system is designed with an integrable optical source consisting of an electro-absorption modulator for pulse carving, compact coders consisting of fiber Bragg grating arrays for encoding and decoding, and receiver consisting of an all-optical thresholder for data and clock recovery. We compare three detection schemes: (1) synchronous detection with data from a photodetector and clock from an external source; (2) asynchronous detection with data and clock from the all-optically thresholded signal received by a clock and data recovery (CDR) unit; and (3) asynchronous detection with data from a photodetector and clock extracted from the all-optically thresholded signal using CDR. Error-free transmission is obtained for detection schemes (1) and (3). A combination of all-optical thresholding and CDR technology is demonstrated in an optical CDMA system for the first time. 相似文献