Method for correcting the signal amplitude of optical data receivers

摘要

In a method for correcting the fluctuations in the signal amplitude of optical data receivers resulting from the change of the polarisation state, the carrier wave and an auxiliary carrier wave generated by an oscillator are divided up via the same polarisation-selective beam splitter into sub-waves and the auxiliary and signal carrier wave components are in each case fed to a photodiode mixer, the resulting IF voltages are amplified in frequency-selective fashion and finally summed. In the case of intensity modulation, the IF voltages are demodulated before the summation through square-law rectification. In the case of angle modulation and similar types of modulation, the IF voltages are phase-matched before the summation.