| 摘要 |
The invention relates to an optical receiver including a transimpedance amplifier (TA), a photodetector (PD) for turning the optical power coming to the receiver into an electric current, whereby the output of the photodetector is connected functionally to the input of the transimpedance amplifier, a controllable impedance element (ZU), which is connected functionally to the input of the transimpedance amplifier, and control units (CU) for controlling the impedance of the impedance element. To be able to increase the dynamic range of the receiver so that the circuit solution remains as simple as possible and, in addition, so that only a minimum reduction of the receiver's sensitivity takes place, a signal is formed in the receiver which is proportional to the power of the optical input signal, and the impedance control is performed entirely on the input side of the transimpedance amplifier by controlling the impedance directly on the basis of said signal so that the impedance will be reduced as the mean power increases. |
