Method and device for creating a control channel in an optical transmission signal and method and device for extracting the information included therein

A device for creating a control channel in an optical transmission signal, comprising an optical transmitter device and a controller device configured to control the optical transmitter device,

• wherein the controller device is configured to create a modulation signal supplied to the optical transmitter device, and
• wherein the optical transmitter device is configured to create an optical transmission signal comprising an optical carrier frequency component, a higher frequency modulation component carrying user information to be transported from a first end of an optical transmission link to a second end of an optical transmission link and a lower frequency modulation component carrying control information, the higher frequency modulation component realizing a user channel and the lower frequency modulation component realizing a control channel, and
• wherein that the controller device is configured to create the modulation signal in the form of a binary digital modulation signal using a binary digital modulation scheme and
• wherein that the optical transmitter device is configured to create the lower frequency modulation component according to the binary digital modulation signal by amplitude-modulating an optical carrier signal or a modulated optical carrier signal, and,
• wherein the controller device and the optical transmitter device are configured in such a way, that the lower frequency modulation component is created in such a way that the lower frequency modulation component comprises a binary digital pilot tone signal component corresponding to a pilot tone signal having a predetermined pilot tone frequency.

A device for extracting the information transported in a control channel of an optical transmission signal,

• wherein the optical transmission signal comprises an optical carrier frequency component, a higher frequency modulation component carrying user information to be transported from a first end to a second end of an optical transmission link and a lower frequency modulation component carrying control information, the higher frequency modulation component realizing a user channel and the lower frequency modulation component realizing the control channel,
• wherein the lower frequency modulation component is created by amplitude modulation,
• wherein the lower frequency modulation component is created using a binary digital modulation scheme and a binary digital modulation signal in such a way that the lower frequency modulation component comprises a binary digital pilot tone signal component corresponding to a pilot tone signal having a predetermined pilot tone frequency, and,
• wherein the optical transmission signal is received and converted into an electrical receive signal by an optical receiver of an optical receiver device and that a Fast Fourier Transform analysis is applied onto the electrical receive signal by a receiver control unit of the optical receiver device in order to determine the frequency and/or the absolute or relative amplitude of the pilot tone.