It is an object to monitor signal flow (optically switched state) in an optical node without using a monitor light. In each of output ports of the optical node, a part of output signals is turned back, and the output signal light is subjected to intensity modulation or phase modulation, assigned port identification information, and allowed to reverse in the optical node. From an input port corresponding to the reversed output signal, a plurality of signals turned back are output. The plurality of signals are appropriately converted into intensity modulation from phase modulation and separated by a device having a spectroscopic function, and identification information is read out based on an intensity of a signal light for each signal, thereby determining an optically switched state to an output port corresponding to the input port.

An optical reception apparatus includes an equalization processor, an extraction unit, a first ratio calculator, and an instruction transmitter. The equalization processor suppresses fluctuations in amplitude of an electrical signal obtained by converting an optical signal including a plurality of pilot symbols subjected to BPSK modulation by an optical transmission apparatus. The extraction unit extracts the pilot symbols from the electrical signal with suppressed fluctuations in amplitude. The first ratio calculator calculates a ratio of an amplitude component to a phase component of each of the pilot symbols extracted by the extraction unit. The instruction transmitter transmits information relating to skew adjustment based on the ratio of the amplitude component to the phase component calculated by the first ratio calculator for each of different control values to the optical transmission apparatus.

A method of operating an RF system, the method including controlling coupling and uncoupling of RF ports included in an M by N radio frequency (RF) switch matrix including N first-side RF ports and M second-side RF ports, wherein each of the first-side RF ports may be selectively coupled to at least one of two or more of the second-side RF ports, such that RF signals are carried between selectively coupled ports; identifying one or more of the second-side RF ports as active ports, the active ports including a first active port; causing the RF switch matrix to couple the first active port to a first signal port included in the first-side RF ports; obtaining a first indication of reduced performance for a first piece of RF communication equipment coupled to the first active port; and causing, in response to the first indication, the RF switch matrix to couple the first signal port to a first spare port, wherein the first spare port is included in the second-side RF ports and is not included in the active ports.

A thyristor switch is constituted of a pair of arms connected in anti-parallel, each of the arms including a plurality of thyristors connected in series. A controller includes a phase detecting unit configured to detect a phase of a power supply voltage supplied from an alternating-current power supply, and a gate signal generating unit configured to interrupt a gate signal when an open command is provided to the static switch and the phase of the power supply voltage detected by the phase detecting unit matches a target phase. The target phase is set outside of a phase range where interruption of the gate signal is prohibited, the phase range being set so as to include a zero crossing point at which a load current is switched in polarity.

A thyristor switch is constituted of a pair of arms connected in anti-parallel, each of the arms including a plurality of thyristors connected in series. A controller includes a phase detecting unit configured to detect a phase of a power supply voltage supplied from an alternating-current power supply, and a gate signal generating unit configured to interrupt a gate signal when an open command is provided to the static switch and the phase of the power supply voltage detected by the phase detecting unit matches a target phase. The target phase is set outside of a phase range where interruption of the gate signal is prohibited, the phase range being set so as to include a zero crossing point at which a load current is switched in polarity.

Methods and apparatuses for enhancing flatness of frequency response of couplings of radio frequency (RF) ports in an RF switch matrix. Techniques include determining a second RF port has been selected to be coupled to a first RF port via a coupling, obtaining an indication of a frequency or frequencies to be carried via the coupling, determining an amount of attenuation or amplification for the coupling for the frequency or frequencies, and adjusting attenuation or amplification applied to the coupling according to the determined amount attenuation or amplification.

An object of the present disclosure is to propose a technique to enumerate intermediate configurations at high speeds. A configuration enumeration device 10 according to the present disclosure enumerates a network configuration in an input layer 21, an intermediate layer 22, and an output layer 23 that minimizes the number of mechanical patch panels provided in mechanical patch panels, by using -quasi-nonblocking configurations, where being 0 indicates a rearrangeably nonblocking configuration and being 1 indicates a strictly nonblocking configuration, for 01, when a minimum value C of wiring capacity of mechanical patch panels having the input layer 21, the intermediate layer 22, and the output layer 23 is obtained.

To provide a wavelength multiplexing device and the like that can effectively identify whether impairment occurs at a location before or after a separation and switching module, a wavelength multiplexing device (100) is connected to one or more optical fiber line systems and to one or more optical transceiver systems and is disposed between the optical fiber lines and optical transceivers so as to input and output optical signals, and is provided with the following: first optical switches (12a-12c) that output an optical signal input from an optical line to an optical transceiver; second optical switches (12d-12f) that output an optical signal input from an optical transceiver to an optical fiber line; and a local optical loopback circuit (13) that feeds back and outputs an optical signal input from an optical transceiver (21-23) to that optical transceiver.

To provide a wavelength multiplexing device and the like that can effectively identify whether impairment occurs at a location before or after a separation and switching module, a wavelength multiplexing device (100) is connected to one or more optical fiber line systems and to one or more optical transceiver systems and is disposed between the optical fiber lines and optical transceivers so as to input and output optical signals, and is provided with the following: first optical switches (12a-12c) that output an optical signal input from an optical line to an optical transceiver; second optical switches (12d-12f) that output an optical signal input from an optical transceiver to an optical fiber line; and a local optical loopback circuit (13) that feeds back and outputs an optical signal input from an optical transceiver (21-23) to that optical transceiver.

A non-blocking crossbar switch architecture circumvents the problem present in prior art crossbar switches where input signals may oversubscribe the available inter-die bandwidth. The new non-blocking crossbar switch architecture is split across a plurality of semiconductor dice, including a plurality of interleaved crossbar switch segments. Only one crossbar switch segment is implemented on each semiconductor die. A plurality of input ports and output ports are coupled to the crossbar switch. The crossbar switch is non-blocking, i.e., any one output port not currently receiving data may receive data from any one input port.