Wavelength-domain simulation of multiwavelength optical networks

This paper presents an efficient simulation method for the design of the op tical transport layer of large-scale multiwavelength optical networks. Acco rding to this method, computations are performed in two complementary steps . During the first step, the powers of optical signals, amplified spontaneo us emission (ASE) noise, and linear optical crosstalk are calculated at all points in the network. During the second step, the distortion and the over all performance of selected optical paths in the network are calculated. Ea ch simulation step requires a different computer representation of optical signals and network components. A large part of this paper is devoted to th e description of the wavelength-domain representation used during the first simulation step, In wavelength domain, optical signals are represented hy their carrier wavelength and average power, exclusively. In addition, the n etwork components are fully characterized by their loss or gain as a functi on of wavelength. The phase-transfer functions of the network components ar e discarded. These simplifications result in a dramatic increase in executi on speed. During the second simulation step, optical signals are represente d by their temporal waveforms. Linear optical network segments are replaced by an equivalent channel. The link between the two simulation steps is exp lained in detail. The remainder of the paper is devoted to the implementati on of a network simulation tool based on the above method in the context of the multiwavelength optical networking (MONET) project. To illustrate the capabilities of the MONET simulator, a mesh of 4 x 4 wavelength-selective c ross connects (WSXC's) and wavelength add-drop multiplexers (WADM's) is stu died and the crosstalk performance is determined.