An S/N calculation circuit 12 to calculate the S/N ratio of a received signal, and an S/N comparison circuit 13 to compare the S/N calculated by the S/N calculation circuit 12 with a threshold Th are disposed, and a parameter setting circuit 14 controls the radiation state of a beam radiated from a transmission optical system 5 according to the result of the comparison performed by the S/N comparison circuit 13. As a result, even if the state of the propagation environment gets worse, degradation in the communication quality can be prevented and communicative stabilization can be achieved.

An S/N calculation circuit 12 to calculate the S/N ratio of a received signal, and an S/N comparison circuit 13 to compare the S/N calculated by the S/N calculation circuit 12 with a threshold Th are disposed, and a parameter setting circuit 14 controls the radiation state of a beam radiated from a transmission optical system 5 according to the result of the comparison performed by the S/N comparison circuit 13. As a result, even if the state of the propagation environment gets worse, degradation in the communication quality can be prevented and communicative stabilization can be achieved.

A system for centralized automatic bias control for a plurality of modulators, including a coupler for coupling output of each of the plurality of modulators to generate a combined modulator output. A pilot insertion device inserts a pilot tone into each of the plurality of modulators such that a different pilot tone frequency is inserted for each of the plurality of modulators. A monitoring device iteratively monitoring power (P.sub.t) of each inserted pilot tone over time to determine whether a current modulator bias is optimal for each of the plurality of modulators, and an adjuster device iteratively adjusts the modulator bias for each of the plurality of modulators for which the current modulator bias is determined to be sub-optimal until a threshold condition has been met.

A system for centralized automatic bias control for a plurality of modulators, including a coupler for coupling output of each of the plurality of modulators to generate a combined modulator output. A pilot insertion device inserts a pilot tone into each of the plurality of modulators such that a different pilot tone frequency is inserted for each of the plurality of modulators. A monitoring device iteratively monitoring power (P.sub.t) of each inserted pilot tone over time to determine whether a current modulator bias is optimal for each of the plurality of modulators, and an adjuster device iteratively adjusts the modulator bias for each of the plurality of modulators for which the current modulator bias is determined to be sub-optimal until a threshold condition has been met.

A connector which serves as an optical transmitter in accordance with an embodiment of the present invention includes: a transmitting circuit configured to convert a data signal into an electric current signal, the data signal being a three-valued; and an LD configured to convert the electric current signal into an optical signal. The transmitting circuit detects, as an IDLE interval, an interval during which the data signal falls within a predetermined range that is between a high level and a low level. The transmitting circuit controls, during the IDLE interval, the electric current signal to be not greater than a threshold electric current of the LD.

A connector which serves as an optical transmitter in accordance with an embodiment of the present invention includes: a transmitting circuit configured to convert a data signal into an electric current signal, the data signal being a three-valued; and an LD configured to convert the electric current signal into an optical signal. The transmitting circuit detects, as an IDLE interval, an interval during which the data signal falls within a predetermined range that is between a high level and a low level. The transmitting circuit controls, during the IDLE interval, the electric current signal to be not greater than a threshold electric current of the LD.

An optical wireless apparatus that is implemented for transmitting an optical wireless signal via an optical wireless channel includes: an electronic signal source that is configured to provide a data signal and an optical signal source that is configured to convert the data signal into the optical wireless and to emit the same. The optical wireless apparatus is configured to obtain channel information including information associated with a non-linear channel distortion of the optical wireless signal and to perform adaptation of a modulation of the optical signal source by changing an operating state of the electronic signal source for adapting the non-linear channel distortion and/or to perform adaptation of an operating point of the optical signal source for adapting the non-linear channel distortion.

Embodiments herein relate to optoelectronic transceivers with power management. An optoelectronic device may include a photodetector, a loss of signal (LOS) detector coupled with the photodetector, and a re-timer coupled with the LOS detector, wherein a component of the re-timer is to be disabled in response to a detection by the LOS detector that an optical signal has not been received for a predetermined time period. In some embodiments, the LOS detector is coupled with a driver disable input of the re-timer and a driver component of the re-timer is to be disabled. In some embodiments, a clock data recovery circuit, a transmit module re-timer and modulator, and/or a laser may be disabled. In various embodiments, components may be re-enabled in response to detection that an optical signal is being received and/or an electrical signal is received for optical transmission. Other embodiments may be described and/or claimed.

Embodiments herein relate to optoelectronic transceivers with power management. An optoelectronic device may include a photodetector, a loss of signal (LOS) detector coupled with the photodetector, and a re-timer coupled with the LOS detector, wherein a component of the re-timer is to be disabled in response to a detection by the LOS detector that an optical signal has not been received for a predetermined time period. In some embodiments, the LOS detector is coupled with a driver disable input of the re-timer and a driver component of the re-timer is to be disabled. In some embodiments, a clock data recovery circuit, a transmit module re-timer and modulator, and/or a laser may be disabled. In various embodiments, components may be re-enabled in response to detection that an optical signal is being received and/or an electrical signal is received for optical transmission. Other embodiments may be described and/or claimed.

The present invention relates to a driver system that can include an optical power based isolated power supply. The driver system can include an optical receiver that can be in communication with an optical transmitter to receive an optical signal. The optical receiver can be configured to convert the optical signal to a drive signal having a determined drive strength. The driver system can further include a driving circuit that can be configured to drive an input of the transistor device based on the drive signal according to a control signal defining an on-time and off-time for the driving circuit over a time interval. In some examples, the driver system can be integrated with a protection system.