Homodyne optical coherent receiver for digital optical signals
AssigneeStc PLC
InventorsStephen Wright, Anthony W. Davis
Life of this patent
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Abstract
A receiver for modulated optical signals including a multiport optical fibre coupler arrangement (10) to one input port of which the modulated optical signals are applied and to another input port of which a local oscillator optical signal of substantially the same optical frequency as the modulated optical signal is applied whereby the output ports of the coupler give separate output signals that are differentially related to the optical frequency phase difference between the modulated input signal and the local oscillator signal, means for individually demodulating (12a-12c) the output signals and means for summing the demodulated output signals.
Claims4
A homodyne optical coherent receiver for modulated optical signals including a multiport optical fibre coupler device having 3 input ports and 3 output ports with energy being coupled from each input port to all the output ports equally, means for applying to one input port a modulated optical signal, means for applying to another input port a local oscillator optical signal of substantially the same optical frequency as the modulated optical signal whereby the output ports of the coupler give separate output signals that are differentially related to the optical phase difference between the modulated input signal and the local oscillator signal, means for individually demodulating the output signals and means for combining the demodulated output signals.
Dependencies are inferred from the claim text.