Abstract: In a synchronous multiplex network including a plurality of multiplex transmission apparatuses, an overhead is passed through intervening multiplex transmission apparatuses such that administration and maintenance operation information is transmitted and received through the overhead between arbitrary multiplex transmission apparatuses. The multiplex transmission apparatus receives a multiplexed signal comprising a payload having a plurality of main signals multiplexed therein and overhead bytes including a plurality of administration and maintenance operation information, performs termination processing for the administration and maintenance operation information and transmission processing for the payload, thereafter converts the multiplexed signal into a different multiplexed signal comprising a payload which has been processed for transmission and a plurality of administration and maintenance operation information, and transmits the different multiplexed signal.

Abstract: An encoder adds an identifier, being different when the coding should be done or not, into a predetermined location in an original signal, while a decoder reads out the identifier added and detects the condition of coding, so as to decide the execution (ON) of the decoding process to be done or not, automatically. Further, in each of the encoder and the decoder, there is provided a delay output portion, which provides an output treated with only a specific delay but not executing the coding/decoding thereon, separately from a coding process portion or a decoding process portion, wherein a selection can be made, at which one of the signals from the respective process portions and the delay output portion should be outputted, by a setup in an outside operation system with use of a selector.

Abstract: An optical transmission network allows transmission monitoring zones to be set up or changed in a flexible manner, and allows simultaneous monitoring of communication quality for each of these monitoring zones. Also, provided is an optical transmission zone service provider that varies user fees according to communication quality in the used zones.

Abstract: An encoder adds an identifier, being different when the coding should be done or not, into a predetermined location in an original signal, while a decoder reads out the identifier added and detects the condition of coding, so as to decide the execution (ON) of the decoding process to be done or not, automatically. Further, in each of the encoder and the decoder, there is provided a delay output portion, which provides an output treated with only a specific delay but not executing the coding/decoding thereon, separately from a coding process portion or a decoding process portion, wherein a selection can be made, at which one of the signals from the respective process portions and the delay output portion should be outputted, by a setup in an outside operation system with use of a selector.

Abstract: A multiplex type transmitting apparatus is arranged to have a plurality of slow signal receive/transmit sections for accommodating a counterpart for a SONET system or an SDH system, a multiplex separation converting section, and a receive/transmit section for a SONET system or SDH system fast signal.

Abstract: A client signal having a constant bit rate is segmented every a bytes to create code information blocks. The bit rate of the client signal is increased such that the client signal has the code information block and an empty area comprised of b bytes, and the ratio c/a is equal to or higher than 110% to create a code block 3 comprised of c bytes. The code information block in the code block is encoded such that an error correcting code is included therein to have an encoding gain of 6 dB or higher for a bit error ratio of 10−12. Associated check bits are placed in the empty area to eventually generate a super FEC signal.

Abstract: In a synchronous multiplex network including a plurality of multiplex transmission apparatuses, an overhead is passed through intervening multiplex transmission apparatuses such that administration and maintenance operation information is transmitted and received through the overhead between arbitrary multiplex transmission apparatuses. The multiplex transmission apparatus receives a multiplexed signal comprising a payload having a plurality of main signals multiplexed therein and overhead bytes including a plurality of administration and maintenance operation information, performs termination processing for the administration and maintenance operation information and transmission processing for the payload, thereafter converts the multiplexed signal into a different multiplexed signal comprising a payload which has been processed for transmission and a plurality of administration and maintenance operation information, and transmits the different multiplexed signal.

Abstract: In a synchronous multiplex network including a plurality of multiplex transmission apparatuses, an overhead is passed through intervening multiplex transmission apparatuses such that administration and maintenance operation information is transmitted and received through the overhead between arbitrary multiplex transmission apparatuses. The multiplex transmission apparatus receives a multiplexed signal comprising a payload having a plurality of main signals multiplexed therein and overhead bytes including a plurality of administration and maintenance operation information, performs termination processing for the administration and maintenance operation information and transmission processing for the payload, thereafter converts the multiplexed signal into a different multiplexed signal comprising a payload which has been processed for transmission and a plurality of administration and maintenance operation information, and transmits the different multiplexed signal.

Abstract: A multiplex type transmitting apparatus is arranged to have a plurality of slow signal receive/transmit sections for accommodating a counterpart for a SONET system or an SDH system, a multiplex separation converting section, and a receive/transmit section for a SONET system or SDH system fast signal.

Abstract: To obtain an optical functional device such that the reflectivity of a facet and the loss of coupling with a fiber are reduced, a mode conversion region for changing the beam spot size is formed on the input facet and/or the output facet in an optical function region and the facet of the side to be connected with a fiber in the mode conversion region is formed obliquely to the direction of propagation of light.

Abstract: A semiconductor device comprises a semiconductor substrate, an active region positioned in a portion of the substrate and a field insulating layer surrounding the active region and partially embedded in the substrate. The semiconductor device according to the present invention further comprises an insulating member positioned under and attached to the bottom of the field insulating layer and surrounding the active region with the field insulating layer. Because of this insulating member, the thickness of the field insulating layer can be reduced to a small value. Therefore, a PN junction formed in the active region can be terminated at the insulating member without any sharp curvature, that is, the PN junction can extend flatly. Further, silicon crystal near the field insulating layer has only a small amount of defects or no defect so that any abnormal diffusion of impurity near the field insulating layer can be prevented.

Abstract: A semiconductor device comprises a semiconductor substrate, an active region positioned in a portion of the substrate and a field insulating layer surrounding the active region and partially embedded in the substrate. The semiconductor device according to the present invention further comprises an insulating member positioned under and attached to the bottom of the field insulating layer and surrounding the active region with the field insulating layer. Because of this insulating member, the thickness of the field insulating layer can be reduced to a small value. Therefore, a PN junction formed in the active region can be terminated at the insulating member without any sharp curvature, that is, the PN junction can extend flatly. Further, silicon crystal near the field insulating layer has only a small amount of defects or no defect so that any abnormal diffusion of impurity near the field insulating layer can be prevented.