Bell Labs

About: Bell Labs is a based out in . It is known for research contribution in the topics: Laser & Optical fiber. The organization has 36499 authors who have published 59862 publications receiving 3190823 citations. The organization is also known as: Bell Laboratories & AT&T Bell Laboratories.

Polarization independent coherent lightwave detection arrangement

Abstract: A polarization independent coherent lightwave detection arrangement is disclosed which utilizes an optical hybrid (11) including a single polarization beam splitter (12) and a set of three polarization maintaining optical couplers (one input (22), two output (16,20)). By controlling the polarization state of the local oscillator to remain at a fixed value, polarization independent recovery of a transmitted data signal may be accomplished. Phase independence may be incorporated by replacing the pair of output polarization maintaining optical couplers with a pair of phase diversity optical hybrids.

On Volterra expansions for time-varying nonlinear systems

Abstract: We extend in an important direction recent results by this writer which show for the first time the existence of a locally convergent Volterra series representation for the input-output relation of a certain large class of nonlinear systems containing an arbitrary finite number of nonlinear elements. (Systems of the type considered arise, for example, in the area of communication system modeling.) The extension covers cases in which the linear part of the system is of a more general type that arises often, and unavoidably leads to considerably more complicated general expressions for the terms in the corresponding series expansions.

On CBR service

Abstract: We investigate the performance of CBR traffic in the context of large-scale networks, where many connections and switches coexist and interact. We develop a framework for simulating such networks, decoupling the influence of breadth and depth. Our results are briefly as follows: we found that a Poisson stream is a good approximation to a superposition of many CBR streams with differing phases and bandwidths. Delays incurred by a reference stream with cross traffic composed of many CBR streams with different bandwidths and phases do not exceed a few cell times even under heavy load, which means that buildout buffers of 10 to 20 cells seem to be sufficient after traversing 20 switches. CBR traffic can be efficiently served by the first come first served (FCFS) scheduling discipline, which has the least implementation cost. Surprisingly, the round robin (RR) and weighted round robin (WRR) disciplines perform worse than the FCFS, despite their greater implementation complexity. We also compare an analytical approximation method based on the multiclass parametric decomposition method, with the simulation results and found it to be suitable for estimating the end-to-end delays for the FCFS discipline.

Quantum Statistics for Distinguishable Particles

Abstract: Quantum statistics can be reconciled with such classical ideas as distinguishable particles. Bose-Einstein and Fermi-Dirac statistics are derived for distinguishable particles by making an assumption regarding probabilities which is different from the traditional assumption but equally reasonable.