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排序方式: 共有83条查询结果,搜索用时 31 毫秒
1.
A.H. Gnauck S. Chandrasekhar P.J. Winzer 《Photonics Technology Letters, IEEE》2006,18(5):697-699
We experimentally demonstrate a 10.7-Gb/s duobinary transmission system operating over a chromatic-dispersion range of /spl sim/12 000 ps/nm. Heterodyne detection and maximum-likelihood sequence estimation are employed to achieve this result. 相似文献
2.
With the aid of the van Cittert-Zernike theorem we develop an analytical expression for the ensemble-averaged heterodyne mixing efficiency in coherent lidar receivers that are looking at a diffuse target that is in the receiver's far field. Our extremely simple and straightforward analysis shows that the dependence of the mixing efficiency on the receive aperture size d(R) first follows a parabolic decrease and later approaches a (d(R))(-2) function. As a consequence, the signal-to-noise ratio does not increase proportionally to the aperture area but saturates. For the system model chosen, the heterodyne mixing efficiency exhibits the same functional dependence on the lidar geometry as the reciprocal of the number of speckle cells within the receive aperture. 相似文献
3.
Advanced Optical Modulation Formats 总被引:7,自引:0,他引:7
Winzer P.J. Essiambre R.-J. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2006,94(5):952-985
Fiber-optic communication systems form the high-capacity transport infrastructure that enables global broadband data services and advanced Internet applications. The desire for higher per-fiber transport capacities and, at the same time, the drive for lower costs per end-to-end transmitted information bit has led to optically routed networks with high spectral efficiencies. Among other enabling technologies, advanced optical modulation formats have become key to the design of modern wavelength division multiplexed (WDM) fiber systems. In this paper, we review optical modulation formats in the broader context of optically routed WDM networks. We discuss the generation and detection of multigigabit/s intensity- and phase-modulated formats, and highlight their resilience to key impairments found in optical networking, such as optical amplifier noise, multipath interference, chromatic dispersion, polarization-mode dispersion, WDM crosstalk, concatenated optical filtering, and fiber nonlinearity. 相似文献
4.
Winzer P.J. Raybon G. Doerr C.R. Duelk M. Dorrer C. 《Lightwave Technology, Journal of》2006,24(8):3107-3113
This paper reports the first optical transmitter implementations operating at a serial bit rate of 107 Gb/s using solely electronic time-division multiplexing. Two methods to overcome modulator bandwidth limitations are proposed and demonstrated: low-bandwidth optical duobinary modulation and integrated optical equalization. Both transmitters are characterized in terms of bit error ratio and chromatic dispersion tolerance. 相似文献
5.
Advanced optical modulation formats have become a key ingredient to the design of modern wavelength-division-multiplexed (WDM) optically routed networks. In this paper, we review the generation and detection of multigigabit/second intensity- and phase-modulated formats and highlight their resilience to key impairments found in optical networking, such as optical amplifier noise, chromatic dispersion, polarization-mode dispersion, WDM crosstalk, concatenated optical filtering, and fiber nonlinearity 相似文献
6.
7.
Freckmann T. Essiambre R.-J. Winzer P.J. Foschini G.J. Kramer G. 《Photonics Technology Letters, IEEE》2009,21(20):1496-1498
In this letter, we calculate theoretical limits to fiber-optic transport capacity under the constraint of requiring the use of concentric multiring modulation alphabets. Subject to these conditions, we vary ring amplitude ratios and occupation probabilities to determine the capacity-optimized ring constellations. The technique used for fiber transmission calculations accurately captures all fiber nonlinear effects, with the accuracy limited by the noise and signal statistical properties only. 相似文献
8.
Wallner O Leeb WR Winzer PJ 《Journal of the Optical Society of America. A, Optics, image science, and vision》2002,19(12):2445-2448
Using the concept of leaky modes, we derive the minimum length of a single-mode fiber required to act as a spatial-mode filter of given quality. The degree of filter action is defined by the ratio of power carried by the fundamental mode to that carried by the leaky modes. 相似文献
9.
Gripp J. Winzer P.J. Raybon G. Simsarian J.E. Doerr C.R. 《Photonics Technology Letters, IEEE》2007,19(15):1124-1126
We demonstrate 107-Gb/s optical packet switching using electronically multiplexed duobinary signals, fast tunable lasers, and a 40 times 40 arrayed waveguide grating router. With a spectral efficiency of 1 bit/s/Hz, the fabric scales to 4-Tb/s capacity and is suitable for 100-Gb Ethernet backplanes. 相似文献
10.