Proposal on adoption of polarization-controlled switch for survivable fiber networks and demonstration of simultaneous FDM/WDM signal switching

A polarization-controlled switch is proposed for use in the construction of survivable fiber networks. This switch ensures high survivability when fibers fail. The switching performance is demonstrated for FSK-modulated FDM signals and intensity-modulated WDM signals. The multiplexed signals are switched simultaneously and no degradation is observed in the bit-error-rate performance. The switch has an almost constant loss and a crosstalk of better than 20 dB in the 1.51-1.59 mm wavelength range, which is much wider than that of the Er/sup 3+/-doped optical amplifier gain spectrum.<
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