Sumitomo Electric Industries, Limited

Daisuke Kawase

Hiromi Kurashima

Daisuke Umeda

Hiroyasu Oomori

Kuniyuki Ishii

Tomoyuki Funada

Naruto Tanaka

Keisuke Jinen

A PON system according to one manner of the present invention includes an optical line terminal (OLT), at least one optical network unit (ONU), and an optical fiber that connects the optical line terminal and the optical network unit to each other. A reception level category for categorizing a reception level in the optical network unit, of an optical signal sent from the optical line terminal through the optical fiber is set. In discovery processing for searching for and registering an unregistered optical network unit, the optical line terminal registers an optical network unit corresponding to the reception level category.

PON system, optical network unit, optical line terminal, method of registering optical network unit, and data structure

An optical transceiver of the present disclosure includes: a first light emitting element configured to perform electric-optic conversion at a first transmission rate; a second light emitting element configured to perform electric-optic conversion at a second transmission rate higher than the first transmission rate; a light receiving element configured to perform optic-electric conversion at a predetermined transmission rate; an optical sub-assembly accommodating the light emitting elements and the light receiving element; a circuit board having a plurality of integrated circuits which are configured to drive the light emitting elements and the light receiving element; a housing accommodating the optical sub-assembly and the circuit board, the housing having a longest dimension in a longitudinal direction thereof and having thermal conductivity; a temperature sensor configured to detect a temperature inside the housing; a temperature control unit configured to determine a control value to be designated to the integrated circuit that corresponds at least one target element among the light emitting elements and the light receiving element, in accordance with a detection temperature detected by the temperature sensor; and a light emission control unit configured to set a light emission state of an apparatus to which the light emission control unit belongs, to any of states 1 to 3 below. The optical sub-assembly is disposed at one end side in the longitudinal direction with respect to a main heat generation member among the plurality of integrated circuits, and the temperature sensor is disposed at another end side in the longitudinal direction with respect to the heat generation member. State 1: a state in which the first light emitting element is ON and the second light emitting element is OFF; state 2: a state in which the first light emitting element is ON and the second light emitting element is ON; and state 3: a state in which the first light emitting element is OFF and the second light emitting element is ON.

Optical transceiver and method for estimating temperature of same

An optical transceiver that attenuates the EMI radiation leaked therefrom is disclosed. The optical transceiver includes a top cover and the bottom base to form a cavity into which a TOSA, a ROSA, and a circuit are set. At least one of the top cover and the bottom base provides a combed structure in a rear portion of the optical transceiver, where the combed structure has a plurality of T-shaped fins to attenuate the EMI radiation.

Optical transceiver having enhanced EMI tolerance

An optical transceiver that reduces the EMI radiation leaked therefrom is disclosed. The optical transceiver includes a top cover and the bottom base to form a cavity into which a TOSA, a ROSA, and a circuit are set. The top cover provides a combed structure in a rear portion thereof, where the combed structure has a plurality of fins with a distance preferably less that quarter wavelength &#x3bb;/4 of the noise wavelength to be reduced. The combed structure operates as a short stub for the electromagnetic wave traveling longitudinally in the cavity.

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Osaka, Japan

Daisuke Kawase