Abstract: Known is an optical receiver (4) in which first a received broadband optical signal is converted to a broadband electric signal by means of a optoelectric converter (49) comprising a transimpedance amplifier, and thereafter a channel is selected from the converted broadband signal by means of a tuner which is coupled to the transimpedance amplifier. Such a configuration is not optimal in fulfilling noise and bandwidth requirements. An optical receiver (4) for subcarrier multiplexed optical signals is proposed which has a tunable frequency selective front-end section (30) that is directly coupled to a photodiode (49) as an optoelectric converter so as to selectively pass a tuned channel from the received subcarrier multiplexed optical signal to a succeeding amplifier (36; 61).

Abstract: To compensate for the non-linear conversion characteristic of the laser diode of an optical transmitter, a linearization circuit is provided which includes the combination of a first circuit including a zener diode and a second circuit including an impedance element. The zener diode is biased to provide a non-linear operating impedance such that the impedance of the combination varies substantially inversely to variations of the non-linear conversion characteristic of the laser diode at different signal levels.