| 摘要 |
PROBLEM TO BE SOLVED: To satisfy polarization and a frequency adaptive condition with a simple system by estimating a signal that is produced as a result of mixture of a signal component that is modulated in a light receiver and a continuous wave optical signal. SOLUTION: A transmitter 1 includes a laser diode 4 and light of the diode 4 is connected to an external modulator. The modulator is driven by a modulation signal 9 and modulates amplitude and phase of the light. A receiver 3 includes a photodiode, a filter and a decision circuit which subsequently follow. The transmitter 1 transmits an information signal as the sum of a modulated signal component Pm and a continuous wave Pcw . The two signal components are mixed by the photodiode in the receiver 3 and form a signal Pbit . A matching filter and the decision circuit in the receiver 3 estimate the input signal Pbit , restore the signal Pm that is modulated from there and restore a data stream 9 from the modulated signal. |
