At least two multiplexers are used for assembling respective multiplexed output signals and are connected by an array of semiconductor optical amplifiers , each channel having correspondingly at least two SOAs connecting it respectively to {HEAD ~ each} of {TAIL ~ the multiplexers} 
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At least two multiplexers are used for assembling respective multiplexed output signals and are connected by an array of semiconductor optical amplifiers , each channel having correspondingly at least two SOAs connecting it respectively to { HEAD ~ each } of { TAIL ~ the multiplexers }
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