Direct Detection of Optical BPSK/QAM Signal without Digital Signal Processing
We experimentally demonstrate the coherent detection of optical BPSK/QAM signals by direct phase
compensation of the phase noise without using a sophisticated digital signal processing algorithm. The phase compensation
is achieved by applying simply an error signal to a phase modulator located at the local oscillator for coherent detection,
where the error signal is generated to keep the same power level for binary/quadrature signals.
Indexterms - Phase Noise, BPSK, QAM, Coherent Detection, Coherent Optical Communication.