The performance of a conventional intensity modulation direct detection analog optical links is limited by the high noise power associated with large optical carrier power. This optical carrier can be suppressed by using optical frequency modulation in conjunction with a frequency discriminator. In this paper, we propose a design of an integrated optical frequency discriminator, based on optica...

Due to the difference in implementing network topologies in the optical and electronic domain, schemes to tolerate link failures in electronic implementations may not be ‘the most efficient ones for optical implementations of multiprocessor networks. Rerouting messages along alternate paths in the network topology is commonly used in electronically implemented networks to tolerate link failures...

We investigate the fundamental insertion loss due to mode mismatch in an optical link involving a single-mode fiber-optic (SMF) transmission with the insertion of a segment of a multimode Cr(4+)-doped fiber (MMCDF). With an MMCDF core diameter of approximately 15.5 microm that matches the SMF, we obtained coupling efficiencies of 60.3% to 87.5% in the entire transmission spectral range of 1,300...

In a wavelength-division-muliplexing (WDM) optical network, the failure of network elements (e.g., fiber links and cross connects) may cause the failure of several optical channels, thereby leading to large data losses. This study examines different approaches to protect a mesh-based WDM optical network from such failures. These approaches are based on two survivability paradigms: 1) path prote...

A drift free synchronization distribution system with femtosecond accuracy is of great interest for free-electronlasers such as FLASH or the European XFEL. Stability at that level can be reached by distributing laser pulses from a mode-locked erbium-doped fiber laser master oscillator over actively optical-length stabilized fiber-links. In this paper we present a prototype of a fiber-link stabi...

We report a method to determine propagation delays of optical 10 Gb/s data traveling through a 75 km long amplified fiber link with an uncertainty of 4 ps. The one-way propagation delay is determined by two-way exchange and cross correlation of short (< 1 ms) bursts of 10 Gb/s data, with a single-shot time resolution better than 2.5 ps. We thus achieve a novel optical communications link suited...

NICT in Japan has developed a radio frequency (RF) dissemination system using an optical fiber link. The phase noise induced during the transmission through the optical fiber is actively cancelled by a compensation system. A proving test has been conducted on the 114-km urban telecom optical fiber link in Tokyo. The transfer stability in the 10 level at an averaging time of 1 day was achieved. ...

We propose a new space-time coding scheme designed to increase the tolerance of fiber-optic communications systems to polarization dependent loss (PDL). A notable increase in the tolerable amount of average link PDL is achieved without affecting the complexity of the overall optical communications link. Other advantages include seamless integration with the broadly deployed blind equalization m...

Aradhana Narula-Tam MIT Lincoln Laboratory, 244 Wood Street, Lexington, MA 02420 [email protected] Eytan Modiano MIT Laboratory for Information and Decision Systems, Cambridge, MA 02139 [email protected] Abstract: With WDM, a single physical link failure may correspond to multiple logical link failures. We consider the design of physical topologies that ensure logical rings can be embedded in a sur...

In this paper we develop network protection schemes against two link failures in optical networks. The motivation behind this work is the fact that the majority of all available links in an optical network suffer from single and double link failures. In the proposed network protection schemes, NPS2-I and NPS2-II, we deploy network coding and reduced capacity on the working paths to provide back...