摘要:
A SCM-PON using WDM includes: an OLT for transferring downstream data from an external service provider through downstream optical signals and transferring upstream data transferred through upstream optical signals to an outside; an ODN for distributing the downstream optical signals from the OLT and multiplexing the upstream optical signals to the OLT; and a plurality of ONUs for processing the downstream optical signals transferred from the OLT through the ODN and transferring upstream data of subscribers for the OLT through the upstream optical signals, wherein the optical signals between the OLT and the ONUs are divided into wavelength channels with different wavelengths and sub-carrier channels obtained by time-dividing the wavelength channels, and the upstream data and the downstream data are transferred through the sub-carrier channels.
摘要:
Disclosed is a method for operating a wavelength-division-multiplexed passive optical network (WDM-PON) including an optical line terminal (OLT) and a plurality of optical network units (ONUs), each of which is connected to the OLT and communicates with the OLT. The method comprises the steps of transmitting a first control channel including allocation information of downstream data channels and allocation information of time slots for the downstream data channels to each of the plurality of ONUs; and transmitting downstream data to the plurality of ONUs using their associated downstream data channels, each having at least one time slot, based on the information included in the first control channel.
摘要:
A TDM PON including: an optical line terminal; a remote node including multiple secondary optical distributors connected to multiple optical network units; and the multiple optical network units generating and outputting a corresponding upstream optical signal. Each of the secondary optical distributors splits an upstream optical signal input from one of the optical network units connected thereto so as to generate split upstream optical signals and transmits one of the upstream optical signals to the optical line terminal, and transmits another upstream optical signal to a different optical network unit.
摘要:
Disclosed is a subcarrier multiplexing type optical communication method including the steps of receiving a first optical signal composed of a plurality of subcarrier channels having different frequencies, creating a second optical signal having a wavelength different from a wavelength of a received signal; and detecting the subcarrier channels from a third optical signal obtained by subjecting the first optical signal to wavelength shift by means of the second optical signal.
摘要:
Disclosed is a subcarrier multiplexing type optical communication method including the steps of receiving a first optical signal composed of a plurality of subcarrier channels having different frequencies, creating a second optical signal having a wavelength different from a wavelength of a received signal; and detecting the subcarrier channels from a third optical signal obtained by subjecting the first optical signal to wavelength shift by means of the second optical signal.
摘要:
A TDM PON including: an optical line terminal; a remote node including multiple secondary optical distributors connected to multiple optical network units; and the multiple optical network units generating and outputting a corresponding upstream optical signal. Each of the secondary optical distributors splits an upstream optical signal input from one of the optical network units connected thereto so as to generate split upstream optical signals and transmits one of the upstream optical signals to the optical line terminal, and transmits another upstream optical signal to a different optical network unit.
摘要:
A passive optical network includes: a central office for generating multiplexed downstream optical signals and receiving an upstream optical signal; a plurality of optical network units for receiving a corresponding downstream optical signal and generating subcarrier channels carrying electrical data of an assigned frequency; and a remote node for photoelectrically converting the channels into electrical data, electro-optically converting the electrical data into at least one upstream optical signal.
摘要:
A passive optical network includes: a central office for generating multiplexed downstream optical signals and receiving an upstream optical signal; a plurality of optical network units for receiving a corresponding downstream optical signal and generating subcarrier channels carrying electrical data of an assigned frequency; and a remote node for photoelectrically converting the channels into electrical data, electro-optically converting the electrical data into at least one upstream optical signal.
摘要:
The present invention relates to a hydrogen production module by an integrated reaction/separation process, and a hydrogen production reactor using the same, and more specifically, provides a hydrogen production apparatus which laminates a plurality of layered unit cells, is mounted in a pressure-resistant chamber, and can be operated at a high pressure, wherein the unit cell comprises a first modified catalyst, and a second modified catalyst opposite to a hydrogen separator. The hydrogen production module can produce hydrogen using a hydrocarbon, carbon monoxide and an alcohol as sources. Particularly, all the modified catalysts are formed into a porous metal plate form, thereby maximizing the heat transfer effect necessary for reaction. While a reaction and separation of hydrogen simultaneously occur, separated reactants permeate the first modified catalyst so as to come in contact with the same, and then pass through the gap between the hydrogen separator and the second modified catalyst opposite to each other. Therefore, it is possible to obtain a high efficiency over the equilibrium conversion rate of reaction temperature, and high purity hydrogen can be obtained.
摘要:
The present invention relates to a multilayer module for hydrogen separation using a pressure-resistant chamber so that unit cells using a metal separation membrane through which only hydrogen selectively passes are stacked to improve separation efficiency, and a mixed gas is uniformly supplied into each of the unit cells. In the multilayer module, the unit cells are stacked on each other, and the mixed gas is supplied into the chamber. Also, mixed gas input ports are each disposed in the side surfaces of the unit cells to supply the mixed gas.