Abstract: In order to solve the problems described above, an object of the present invention is to provide an optical communication system and a control method that automatically adjust a branching ratio of an optical splitter in accordance with a connection of a new ONU. An optical communication system according to the present invention causes an operation system or a DBA (Dynamic Bandwidth Allocation) function and a determining unit of a branching ratio of an optical splitter to cooperate with each other, adjusts the branching ratio so as to enable ranging with an active ONU, and takes into consideration an initial connection sequence through which an ONU is newly connected.

Abstract: An optical communication system according to the present invention cancels waveform distortion due to wavelength dispersion by extracting the spectrum of a transmitted optical signal and passing the optical signal to a fiber having a dispersion value opposite to a dispersion amount corresponding to a transmission distance received by the spectrum component and compensates for a transmission path loss due to the fiber having the opposite dispersion value using optical splitters having different split ratios. With this configuration, the present invention can compensate for waveform distortion due to wavelength dispersion by a simple method in an access network and achieve an increase in the reachable transmission distance of the farthest user or an increase in the number of connectable users.

Abstract: An object of the present invention is to provide an optical communication system and an optical communication method capable of achieving a long transmission distance with a passive element and obtaining redundancy of a ring topology. The optical communication system according to the present invention is a PON system having a ring configuration, in which an unequal branch optical splitter having a left-right symmetrical configuration is disposed in a trunk fiber wired in a loop shape. An OLT and an ONU have a configuration in which two sets of Tx (transmitter) and Rx (receiver) are mounted. Two sets of Tx (transmitters) and Rx (receivers) in each of a plurality of ONUs are respectively connected to left and right symmetrical ports of one unequally branched light beam SP.

Abstract: An objective is to provide a terminal device, a communication method, and a communication system in which the time taken by connection operations/authentication operations does not increase proportionally with the pattern length, even if the transmitting side and the receiving side are not synchronized. A terminal device, a communication method, and a communication system according to the present invention create n pieces of signal information (n-bit patterns) by sequentially shifting each bit of a single piece of received signal information (n-bit pattern) one bit at a time. Through the above, signal information time-shifted by one bit each is obtained. Thus, even if the transmitting side and the receiving side are not synchronized, one of the n pieces of signal information is a signal synchronized with the transmitting side. Thereafter, the signal synchronized with the transmitting side can be detected by a brute-force calculation with the patterns (ID information) in the list.

Abstract: An object is to provide a terminal device, a communication method, and a communication system which are capable of acquiring accurate optical ID information regardless of the position of the terminal device and the light receiving angle. The terminal device, the communication method, and the communication system according to the present invention each sets a threshold value for the illuminance of a received optical signal by using a moving average method, a weighted moving average method, or an exponential moving average, so that the optical signal can be binarized with a threshold value according to a change in the position of the terminal device, the light receiving angle, or the like. Information from other sensors may be used to set the threshold value.

Abstract: An object of the present invention is to provide a terminal device, a communication method, and a communication system which are capable of reducing the error rate even if the transmitting side and the receiving side are asynchronous. The terminal device, communication method, and communication system according to the present invention sample an optical signal more finely than a 0/1 bit pattern in optical ID estimation processing for determining which of 1/0 the data acquired by an optical sensor is, and perform a majority decision using a plurality of sampling values in a decision processing window. Thus, even if the correct sampling value fails to be obtained, the correct bit value can be derived from other samplings.

Abstract: Provided is a start-stop control apparatus to be mounted in a vehicle including an engine, a starter motor configured to restart the engine, and an auxiliary battery configured to supply electric power to the starter motor. The start-stop control apparatus includes a stop processing unit and an engine measuring unit. The stop processing unit stops idling of the engine while the vehicle is being stopped. The engine measuring unit measures an internal loss of the engine. The stop processing unit determines whether to stop the idling of the engine on the basis of the internal loss measured by the engine measuring unit and the state of charge of the auxiliary battery.

Abstract: An objective is to provide a communication system, a terminal, a communication method, and a program capable of improving the probability of successful authentication regardless of mobility of the terminal.

Abstract: The present disclosure aims to enable communication to be performed with stable quality even when a user uses a terminal while moving. In the wireless communication system according to the present disclose, a switching control unit 15 sets switching illuminance pth for maintaining illuminance of an optical signal received by a terminal 91 at requested illuminance corresponding to throughput or higher during the time until connection switching between the communication with an optical wireless access point 92 and the communication with an RF wireless access point 93 is completed, and when the received illuminance p becomes lower than the switching illuminance pth during connection with the optical wireless access point 92, the switching control unit 15 performs connection switching from the optical wireless communication to the RF wireless communication.

Abstract: An object is to provide a communication system, a base station, and a communication method that can avoid a state in which an RF wireless communication cannot be started due to the quality of optical wireless communication. In an optical communication system according to the present invention, a base station device repeatedly transmits an authentication information frame addressed to a terminal device at a predetermined cycle by the optical wireless communication, the frame including authentication information for connection to the terminal device by the RF wireless communication. Even if the terminal fails to acquire the authentication information at a certain timing due to the quality of optical wireless communication, the communication system has a mechanism that acquires the same authentication information at regular time intervals, so that terminal authentication processing can be performed at the time when the terminal acquires the authentication information.

Abstract: A radio terminal station device includes a communication unit, an information acquisition unit, a threshold calculation unit, a detection unit, and a system selection unit. The communication unit selects any one of a plurality of different communication systems and performs a radio communication. The information acquisition unit acquires information including a communication state of the radio terminal station device and at least communication states of other radio terminal station devices. The threshold calculation unit calculates a threshold value for detecting deterioration of the communication state of the radio terminal station device. The detection unit detects the deterioration of the communication state of a communication system used by the radio terminal station device.

Abstract: According to the present disclosure, a wireless base station device delivers, to a wireless terminal device, an optical ID having a simple configuration in accordance with a pre-stored optical ID correspondence list; and the wireless terminal device selects connection authentication information corresponding to the received optical ID from a pre-stored optical ID correspondence list, and transmits predetermined authentication information to the wireless base station device through a predetermined connection method by RF wireless. Upon confirming that the received authentication information matches authentication information corresponding to an optical ID in the optical ID correspondence list, the wireless base station device permits information communication between the wireless terminal device and a higher-level network.

Abstract: An objective of the present invention is to provide an optical measurement device capable of performing remote optical measurement. An optical measurement device may include a light source that generates irradiation light with a beam shape, a beam control unit configured to control an irradiation direction of the irradiation light L1, a condensing unit configured to condense returned light generated by irradiating a part of a measurement target with the irradiation light, and a detection unit configured to detect information regarding the measurement target included in the returned light condensed by the condensing unit. The beam control unit can control the irradiation direction of the irradiation light for measurement to any direction, and thus the condensing unit can efficiently receive the faint returned light from the measurement target.

Abstract: A control station device includes a policy generation unit that calculates a priority order of a plurality of wireless communication systems having different types of systems on a basis of information acquired from a wireless terminal device that selects one wireless communication system from among the plurality of wireless communication systems to perform wireless communication, and generates a selection policy indicating the priority order of the plurality of wireless communication systems, and a policy delivery unit that delivers the selection policy indicating the priority order of the plurality of wireless communication systems to the wireless terminal device. With this configuration, an optimal wireless communication system that maximizes the performance of each wireless terminal device can be selected while reducing the load and calculation time imposed on the control station device.

Abstract: In the present disclosure, a wireless base station apparatus sends out continuous light having a predetermined characteristic to a wireless terminal apparatus, and the wireless terminal apparatus selects authentication information corresponding to the predetermined characteristic, and transmits the authentication information to the wireless base station apparatus by RF wireless. When confirming that the received authentication information matches authentication information corresponding to the predetermined characteristic, the wireless base station apparatus permits information communication between the wireless terminal apparatus and an upper network.

Abstract: The purpose of the present invention is to provide an optical/RF wireless hybrid communication system and a control method capable of solving the instability of link conditions of an RF wireless link and an optical wireless link. In the optical/RF wireless hybrid communication system and the control method according to the present invention, links for data transmission are not limited to one of an RF wireless link and an optical wireless link, the quality of link conditions is determined from signal quality received through channels of both the RF wireless link and the optical wireless link, and the distribution of data to be transmitted through the respective links is determined on the basis of the determination result. Thus, the links can be flexibly switched depending on the transmission conditions such as disturbance.

Abstract: An object is to provide an optical communication system and an optical communication method that are capable of, when assigning wavelengths on a per-service basis and providing services on a per-area basis, preventing degradation of signal quality due to linear crosstalk and preventing an increase in cost and size. An optical communication system according to the present invention includes an optical splitter 300 connecting N first ports and M second ports by a combination of 2×2 fiber optical splitters, N and M each being an integer of two or more, where wavelengths of optical signals to be received are limited for each group of optical receivers 106, by using a correlation between a fused extension length of at least one 2×2 fiber optical splitter directly connected to the first port, among the 2×2 fiber optical splitters, and wavelength output characteristics of the second port of the optical splitter 300.

Abstract: An object is to provide an optical communication system capable of controlling the output ratio by port and by wavelength for incident light of different wavelengths, a method of determining the split ratio of an uneven-split optical splitter for controlling the output ratio by port and by wavelength, and a transmission range determination method for the optical communication system. The split ratio determination method for an uneven-split optical splitter according to the present invention uses the melt-draw distance to adjust the split ratio of each fiber-optic splitter included in the uneven-split optical splitter such that the light output from the farthest ONUs among each of the ports connected under the ports B to M of the uneven-split optical splitter arrives with the minimum reception sensitivity at OLT receivers in a PON system.

Abstract: To provide an optical communication system and an optical communication method able to achieve a high reliable access network capable of long haul distance transmission considering the optical energy efficiency even if the user distribution is biased. An uneven branch optical splitter included in an optical communication system according to the present invention can output the optical intensities different for each output port by adjusting the branching configuration and the branching ratio. For example, a reach transmission distance of the farmost user can be extended or the number of connectible users can be increased by adjusting the branching configuration of the uneven branch optical splitter or the branching ratios such that the near minimum reception sensitivity is given for the ONU installed near the telecommunications carrier.

Abstract: Provided is a start-stop control apparatus to be mounted in a vehicle including an engine, a starter motor configured to restart the engine, and an auxiliary battery configured to supply electric power to the starter motor. The start-stop control apparatus includes a stop processing unit and an engine measuring unit. The stop processing unit stops idling of the engine while the vehicle is being stopped. The engine measuring unit measures an internal loss of the engine. The stop processing unit determines whether to stop the idling of the engine on the basis of the internal loss measured by the engine measuring unit and the state of charge of the auxiliary battery.