Abstract: A signal processing device includes an electric connector to which a transmitting and receiving device, which transmits and receives a signal, is connectable; a first processor configured to compensate for, according to a setting value, deterioration of the signal input and output between the signal processing device and the transmitting and receiving device via the electric connector; a memory configured to store first characteristic data indicating a transmission characteristic of the signal in the electric connector; and a second processor configured to acquire, from the transmitting and receiving device, second characteristic data for indicating a transmission characteristic of the signal in the transmitting and receiving device and set the setting value in the first processor based on the first characteristic data and the second characteristic data.

Abstract: A signal processing device includes an electric connector to which a transmitting and receiving device, which transmits and receives a signal, is connectable; a first processor configured to compensate for, according to a setting value, deterioration of the signal input and output between the signal processing device and the transmitting and receiving device via the electric connector; a memory configured to store first characteristic data indicating a transmission characteristic of the signal in the electric connector; and a second processor configured to acquire, from the transmitting and receiving device, second characteristic data for indicating a transmission characteristic of the signal in the transmitting and receiving device and set the setting value in the first processor based on the first characteristic data and the second characteristic data.

Abstract: An optical transmission device includes an optical modulator and a processor. The optical modulator optically modulates an optical signal with a driving signal to output a modulated optical signal. The processor performs ABC on a bias of the optical modulator, using the modulated optical signal, so as to cause the bias to converge to an optimum point. The processor starts the ABC using a modulated optical signal optically modulated with a QPSK signal at start-up timing, acquires an optimum value that is a bias value when the bias converges to the optimum point, and stops the ABC. After the ABC is stopped, the processor sets the acquired optimum value as an initial value, and restarts the ABC using a modulated optical signal optically modulated with an N-QPSK signal.

Abstract: An optical transmission device includes an optical modulator and a processor. The optical modulator optically modulates an optical signal with a driving signal to output a modulated optical signal. The processor performs ABC on a bias of the optical modulator, using the modulated optical signal, so as to cause the bias to converge to an optimum point. The processor starts the ABC using a modulated optical signal optically modulated with a QPSK signal at start-up timing, acquires an optimum value that is a bias value when the bias converges to the optimum point, and stops the ABC. After the ABC is stopped, the processor sets the acquired optimum value as an initial value, and restarts the ABC using a modulated optical signal optically modulated with an N-QPSK signal.

Abstract: An optical transmitter includes: a modulator; and a controller configured to control an extinction state, brought about by the modulator, through I control and Q control in which an offset is added to ? bias and ? control which is performed in a state in which the offset is added to I bias and Q bias.

Abstract: An optical transmission system includes a transmitting device and a receiving device, wherein the transmitting device includes a modulating unit that changes a frequency of an optical signal, and the receiving device includes a filtering unit that passes an optical signal in a predetermined frequency band; a measuring unit that measures an intensity of an optical signal that passes through the filtering unit; a detecting unit that detects a center wavelength of the optical signal in accordance with an intensity of the optical signal that is measured when a frequency of the optical signal is changed in a state of a passed band that corresponds to the optical signal; and an output unit that outputs information that indicates the detected center wavelength to the transmitting device, wherein the transmitting device controls a wavelength of the optical signal in accordance with the information from the receiving device.

Abstract: A transmission device includes: optical transmitters configured to transmit optical signals of different wavelengths; optical couplers configured to multiplexing the optical signals transmitted from the optical transmitters; and a wavelength selective switch configured to multiplex multiplexed optical signals obtained by multiplexing by the couplers, wherein optical signals, a wavelength interval between which is less than a predetermined value, are transmitted to separate optical couplers of the optical couplers, among the optical signals.

Abstract: An optical transmission system includes a transmitting device and a receiving device, wherein the transmitting device includes a modulating unit that changes a frequency of an optical signal, and the receiving device includes a filtering unit that passes an optical signal in a predetermined frequency band; a measuring unit that measures an intensity of an optical signal that passes through the filtering unit; a detecting unit that detects a center wavelength of the optical signal in accordance with an intensity of the optical signal that is measured when a frequency of the optical signal is changed in a state of a passed band that corresponds to the optical signal; and an output unit that outputs information that indicates the detected center wavelength to the transmitting device, wherein the transmitting device controls a wavelength of the optical signal in accordance with the information from the receiving device.

Abstract: A transmission device includes: optical transmitters configured to transmit optical signals of different wavelengths; optical couplers configured to multiplexing the optical signals transmitted from the optical transmitters; and a wavelength selective switch configured to multiplex multiplexed optical signals obtained by multiplexing by the couplers, wherein optical signals, a wavelength interval between which is less than a predetermined value, are transmitted to separate optical couplers of the optical couplers, among the optical signals.