文摘
The homodyne coherent detection with Costas loop has been analyzed by considering the shot noise and phase noise. The phase error variance and bit error rate of the coherent detection system have been derived and analyzed in theory. The influences of linewidth of laser, the incoming signal laser power, phase error and the photodiode responsivity for the detectors on the bit error rate have been investigated in detail. The results obtained in this analysis have the potential application for the free space laser communication used the coherent detection.