Soliton generator

Abstract

It has been determined that optical fibers possess a small amount of nonlinearity and, therefore, they are not exactly linear waveguides. This small amount of nonlinearity enables certain special pulse shapes to establish themselves and travel long distances without changing shape. These special pulse shapes are called solitons. This invention relates to a device for generating solitons by amplitude modulating an optical signal with separate in-phase electrical signals of different harmonically related frequencies. Specifically, an amplitude modulator such as a Y junction Mach-Zehnder interferometer has multiple sets of distributed electrodes. The interferometer has a set of electrodes for each electrical signal of a specific frequency. Thus, if three separate signals of harmonically related frequencies are used to amplitude modulate an optical signal, then the interferometer has three sets of electrodes located between the Y junctions of the Mach-Zehnder interferometer. The structure of a separate set of electrodes for each of the signals results in a soliton generator which avoids the prior art problem of signal loss caused by combining many high frequency signals into a composite signal and the resulting need for a relatively expensive amplifier capable of uniformly amplifying the multioctive composite signal.