[Problem] To reduce a time synchronization error caused by upstream and downstream asymmetry of the transmission path, improve wavelength band utilization efficiency, and reduce the required number of transponders.

[Solution] An optical transmission device of each node simultaneously sends a plurality of signals having different wavelengths as delay measurement signals to a transmission path. The optical transmission device determines a delay value that reflects a propagation delay calculated based on an arrival time difference between a plurality of wavelengths in a signal received from another node, and determines a waiting time amount based on the delay value and the propagation delay. The optical transmission device notifies the other node of the delay value. Each optical transmission device outputs the received signal from the other node with a delay of the waiting time amount. The optical transmission device generates an optical intermittent signal obtained by selecting and multiplexing any of time information, the delay measurement signal, and communication information. A reception side extracts a desired multiplexed signal from the received optical intermittent signals.

An optical transceiver module includes an optical transceiver and a controller. The optical transceiver has a ring filter configured to transmit optical signals from or receive optical signals for the optical transceiver module. The controller is configured to: detect a carrier frequency at the optical transceiver; detect a data signal frequency of data at the optical transceiver; determine a bit error rate of the data; and in response to determining that the bit error rate of the data is greater than a threshold, periodically vary a central wavelength of the ring filter at a frequency at least three orders slower than the data signal frequency.

An optical transceiver module includes an optical transceiver and a controller. The optical transceiver has a ring filter configured to transmit optical signals from or receive optical signals for the optical transceiver module. The controller is configured to: detect a carrier frequency at the optical transceiver; detect a data signal frequency of data at the optical transceiver; determine a bit error rate of the data; and in response to determining that the bit error rate of the data is greater than a threshold, periodically vary a central wavelength of the ring filter at a frequency at least three orders slower than the data signal frequency.

A ring interconnect system comprises a plurality of nodes. Each node is connected to two other nodes to form a ring interconnect. Every pair of nodes is connected by an inter-node path for that pair of nodes distinct from the ring interconnect. Each of the nodes comprises a message buffer to buffer messages received from at least one device associated with the node. Each of the nodes also comprises activity level circuitry to transmit an activity indication, when a number of the messages in the message buffer is equal to or above a threshold, to each other node of the plurality of nodes via the respective inter-node paths. Each of the nodes also comprises arbitrator circuitry to receive the activity indications from each other node and from the activity level circuitry, and to allow ingress of a message from the message buffer onto the ring interconnect in dependence on the activity indications. Also provided is a method of operating a node of a ring interconnect system.

A ring interconnect system comprises a plurality of nodes. Each node is connected to two other nodes to form a ring interconnect. Every pair of nodes is connected by an inter-node path for that pair of nodes distinct from the ring interconnect. Each of the nodes comprises a message buffer to buffer messages received from at least one device associated with the node. Each of the nodes also comprises activity level circuitry to transmit an activity indication, when a number of the messages in the message buffer is equal to or above a threshold, to each other node of the plurality of nodes via the respective inter-node paths. Each of the nodes also comprises arbitrator circuitry to receive the activity indications from each other node and from the activity level circuitry, and to allow ingress of a message from the message buffer onto the ring interconnect in dependence on the activity indications. Also provided is a method of operating a node of a ring interconnect system.

An optical transmission device of each node simultaneously sends a plurality of signals having different wavelengths as delay measurement signals to a transmission path. The optical transmission device determines a delay value that reflects a propagation delay calculated based on an arrival time difference between a plurality of wavelengths in a signal received from another node, and determines a waiting time amount based on the delay value and the propagation delay. The optical transmission device notifies the other node of the delay value. Each optical transmission device outputs the received signal from the other node with a delay of the waiting time amount. The optical transmission device generates an optical intermittent signal obtained by selecting and multiplexing any of time information, the delay measurement signal, and communication information. A reception side extracts a desired multiplexed signal from the received optical intermittent signals.

An object of the present invention is to provide a communication system and a communication method that can suppress an increase in the total fiber distance even if the number of secondary devices increases and that can make complex processing for band allocation for uplink optical signals unnecessary. The configuration of the communication system according to the present invention is a mixture of a ring type and a branch type, in which an optical fiber cable (primary path) from a communication station to each user's home is arranged in a ring (loop) shape, and the primary path is branched and laid to the user's home. Furthermore, unidirectional communication is enabled by a ring-type primary path, and the transmittable amount can be made uniform by further combining time division multiplexing.

A system, automobile, and method for implementing an electronic control function of an automobile. The system includes a first vehicle integration unit (VIU), an automobile control unit, and a plurality of automobile parts. The automobile control unit includes a first domain controller (DC) or a central computing platform (CCP). The automobile control unit is configured to send first control information to the first VIU. The first VIU is configured to control the plurality of automobile parts based on the first control information. In embodiments of this application, the first VIU controls the plurality of automobile parts.

A system, automobile, and method for implementing an electronic control function of an automobile. The system includes a first vehicle integration unit (VIU), an automobile control unit, and a plurality of automobile parts. The automobile control unit includes a first domain controller (DC) or a central computing platform (CCP). The automobile control unit is configured to send first control information to the first VIU. The first VIU is configured to control the plurality of automobile parts based on the first control information. In embodiments of this application, the first VIU controls the plurality of automobile parts.

[Problem] To provide a novel optical network which can be used as an in-vehicle optical backbone network and exhibits high capacity, low delay, low power consumption, low noise and low cost. [Solution] An optical network system, wherein: a signal processing unit 13 controls a light source 11, and generates an optical signal which includes an information portion to be read by one of the gateway units 5a, and a continuous light portion to be written thereby; a network control unit 15 generates an electrical signal which designates a gate y unit 5a and pertains to whether the information incorporated into the optical signal is to be read or written; and when designated by the electrical signal, each of the gateway units 5a transfers information to and from an electronic control unit 7, and reads information included in the corresponding optical signal or writes information in the continuous light portion, on the basis of the information included in the electrical signal about whether to read or write information.