Wavelength-division multiplexing

About: Wavelength-division multiplexing is a research topic. Over the lifetime, 25059 publications have been published within this topic receiving 332027 citations. The topic is also known as: WDM.

Joint Digital Signal Processing Receivers for Spatial Superchannels

Abstract: We discuss the advantages of spatial superchannels for future terabit networks based on space-division multiplexing (SDM), and demonstrate reception of spatial superchannels by a coherent receiver utilizing joint digital signal processing (DSP). In a spatial superchannel, the SDM modes at a given wavelength are routed together, allowing a simplified design of both transponders and optical routing equipment. For example, common-mode impairments can be exploited to streamline the receiver's DSP. Our laboratory measurements reveal that the phase fluctuations between the cores of a multicore fiber are strongly correlated, and therefore constitute such a common-mode impairment. We implement master-slave phase recovery of two simultaneous 112-Gbps subchannels in a seven-core fiber, demonstrating reduced processing complexity with no increase in the bit-error ratio. Furthermore, we investigate the feasibility of applying this technique to subchannels carried on separate single-mode fibers, a potential transition strategy to evolve today's fiber networks toward future networks using multicore fibers.

Cross-phase modulation in multispan WDM optical fiber systems

Abstract: The spectral characteristics of cross-phase modulation (XPM) in multispan intensity-modulation direct-detection (IM-DD) optical systems are investigated, both experimentally and theoretically. XPM crosstalk levels and its spectral features are found to be strongly dependent on fiber dispersion and optical signal channel spacing. Interference between XPM-induced crosstalk effects created in different amplified fiber spans is also found to be important to determine the overall frequency response of XPM crosstalk effects. XPM crosstalk between channels with different data rates is evaluated. The crosstalk level between higher and lower bit rate channels is found to be similar to that between two lower bit rate channels. The effect of dispersion compensation on XPM crosstalk in multispan optical systems is discussed and per span dispersion compensation was found to be the most effective way to minimize the effect of XPM crosstalk.

Wavelength division multiplexing of continuous variable quantum key distribution and 18.3 Tbit/s data channels

Abstract: Quantum key distribution (QKD) can offer communication with unconditional security and is a promising technology to protect next generation communication systems. For QKD to see commercial success, several key challenges have to be solved, such as integrating QKD signals into existing fiber optical networks. In this paper, we present experimental verification of QKD co-propagating with a large number of wavelength division multiplexing (WDM) coherent data channels. We show successful secret key generation over 24 h for a continuous-variable QKD channel jointly transmitted with 100 WDM channels of erbium doped fiber amplified polarization multiplexed 16-ary quadrature amplitude modulation signals amounting to a datarate of 18.3 Tbit/s. Compared to previous co-propagation results in the C-band, we demonstrate more than a factor of 10 increase in the number of WDM channels and more than 90 times higher classical bitrate, showing the co-propagation with Tbit/s data-carrying channels. The security of communications networks is a fundamental challenge of the current era, particularly with the move towards quantum communications. The authors perform joint transmission of quantum key distribution and up to 100 classical communication channels in the same fiber and report an average secret key rate of 27.2 kbit/s over a 24 h operation period where the classical data rate amounted to 18.3 Tbit/s.

Wavelength division multiple access channel hypercube processor interconnection

Abstract: A hypercube-based structure in which optical multiple access channels span the dimensional axes is introduced. This severely reduces the required degree, since only one I/O port is required per dimension. However, good performance is maintained through the high-capacity characteristics of optical communication. The reduction in degree is shown to have significant system complexity implications. Four star-coupled configurations are studied as the basis for the optical multiple access channels, three of which exhibit the optical self-routing characteristic. A performance analysis shows that through the integration of agile sources or receivers, and wavelength division multiple access, systems can be developed with significant increases in performance yet at a reduction in communication subsystem complexity. >