Patent application number | Description | Published |
20100150560 | APPARATUS AND METHOD FOR TRANSMITTING OPTICAL SIGNALS WITH ENHANCED REFLECTION SENSITIVITY IN WAVELENGTH DIVISION MULTIPLEXING PASSIVE OPTICAL NETWORK (WDM-PON) - Disclosed are an optical transmission apparatus and method in a wavelength division multiplexing passive optical network (WDM-PON). The optical transmission apparatus outputs an optical signal by applying a DC bias current and an RF signal to a laser diode at a threshold current level of the laser diode, thereby broadening an optical spectrum of the laser diode. Accordingly, an optical link becomes less vulnerable to reflection induced noise, which contributes to improve stability and reliability of the optical link. | 06-17-2010 |
20100150561 | OPTICAL RECEIVER, OPTICAL LINE TERMINAL AND METHOD OF RECOVERING RECEIVED SIGNALS - An optical receiver is provided which can be applied to a wavelength division multiplexing passive optical network (WDM PON) based on a reflective semiconductor optical amplifier employing a wavelength reuse scheme. The optical receiver includes a photo diode to convert an optical signal to an electrical signal; a pre-amplifier to linearly amplify the electrical signal and convert the amplified electrical signal to a voltage signal; a post-amplifier, which is equipped with a gain control function, to convert the voltage signal to a signal with a constant output level and to control a decision threshold of the converted signal; and an offset voltage generator to generate a predetermined offset voltage for the decision threshold control of the post-amplifier and to provide the offset voltage to the post-amplifier. Accordingly, it is possible to increase an extinction ratio of a downstream optical signal to a predetermined level in the WDM PON based on a reflective semiconductor optical amplifier employing a wavelength reuse scheme, and it is possible to reduce an optical power, which is received by the reflective semiconductor optical amplifier incorporated in a subscriber terminal, below a predetermined level. As a result, it is possible to improve transmission quality of the downstream and upstream optical signals. | 06-17-2010 |
20100150574 | METHOD AND APPARATUS FOR CONTROLLING REFLECTIVE SEMICONDUCTOR OPTICAL AMPLIFIER (RSOA) - A method and apparatus for controlling a reflective semiconductor optical amplifier (RSOA) are provided. The RSOA control apparatus sets a threshold current at which a light source starts to oscillate to be constant regardless of a wavelength of seed light by controlling a driving temperature for driving a RSOA, and adjusts an optical characteristic which is differently output for each wavelength of seed light to be constant by controlling a driving current. | 06-17-2010 |
20100158522 | SEED LIGHT MODULE BASED ON SINGLE LONGITUDINAL MODE OSCILLATION LIGHT SOURCE - A seed light module based on a single longitudinal mode oscillation light source is provided. The seed light module includes a multi-wavelength signal generation light source unit generating a continuous wave (CW) of different wavelengths, a multiplexer wavelength-division multiplexing the light output from the light source unit, a polarization beam splitter splitting the light of multiple wavelength components output from the multiplexer according to specific polarization components, phase modulators phase-modulating signals of a first polarization component and a second polarization component split by the polarization beam splitter onto a sine wave having a frequency and amplitude, a radio frequency (RF) signal generator generating the sine wave, a RF signal distributor distributing the generated RF signal, amplifiers amplifying the distributed RF signals, and a polarization beam combiner combining the lights phase-modulated by the respective phase modulators and providing the combined light as a seed light output. | 06-24-2010 |
20100158526 | OPTICAL TRANSCEIVER SUITABLE FOR USE IN HYBRID, PASSIVE OPTICAL NETWORK - Provided is an apparatus for connecting a wavelength division multiplexing passive optical network (WDM-PON) to a time division multiplexing passive optical network (TDM-PON). In a hybrid, passive optical network which is a combination of the WDM-PON and the TDM-PON, the apparatus is formed at a subscriber side for matching the WDM-PPN and the TDM-PON. Accordingly, a passive remote mode can be implemented as a passive node not an active node. Therefore, the entire optical network can be efficiently operated. In addition, since the apparatus located on the subscriber side uses a wavelength-tunable light source, any dependency on the wavelength of a WDM-PON optical signal is removed. | 06-24-2010 |
20110044691 | APPARATUS AND METHOD FOR DETECTING OPTICAL SIGNALS - Disclosed are an apparatus and method for detecting optical signals. The optical signal detection apparatus includes: a signal receiver to convert a received optical signal into an electrical signal; a threshold decision unit to establish a mathematical model based on the electrical signal and to decide an optimized threshold value based on the mathematical model; and a signal detector to detect the electrical signal based on the optimized threshold value. Hence, since threshold values optimized adaptively according to received signals are used, a bit error rate may be lowered and accordingly detection performance may be improved. | 02-24-2011 |
20120128360 | OPEN OPTICAL ACCESS NETWORK SYSTEM - The present invention relates to an open optical access network system in which one optical access network is open to enable a plurality of service providers and a plurality of subscribers to simultaneously use the optical access network, to thereby improve the efficiency of using the optical access network, wherein each subscriber can be provided with a plurality of different services from the plurality of service providers, thereby enabling the flexible selection of services and the flexible change in services, thus improving the efficiency of using an optical infrastructure. | 05-24-2012 |
20120144214 | OPTICAL NETWORK UNIT, POWER SOURCE EQUIPMENT AND POWER SUPPLY SYSTEM USING THE SAME - An optical network unit is provided that includes a communication detector configured to detect whether a communication is achieved between the ONU and at least one power source equipment (PSE), and a power controller configured to detect whether the PSE is powered and to control electrical power, which is provided from the PSE, based on at least one of the detection result about whether the communication is achieved between the ONU and the PSE and the detection result about the PSE is powered. | 06-07-2012 |
20120148191 | ANGLED PHYSICAL CONTACT RECEPTABLE STUB AND ANGLED PHYSICAL CONTACT TRANSMITTER OPTICAL SUB-ASSEMBLY HAVING THE SAME - An APC receptacle stub and an APC TOSA having the same are provided. The APC receptacle stub includes a first APC stub and a second APC stub. The first APC stub has an optical fiber inserted thereto and is provided with one end section polished in an APC shape. The second APC stub has an optical fiber inserted thereto and is provided with one end section polished in an APC shape and an opposite end section which is coupled to an opposite end section of the first APC stub through rotation adjustment in the same axial direction as an axial direction of the opposite end section of the first APC stub. The APC receptacle stub enables easy optical alignment and is applicable to a light source that is sensitive to reflection. | 06-14-2012 |
20120155876 | SEED LIGHT MODULE FOR WAVELENGTH DIVISION MULTIPLEXING-PASSIVE OPTICAL NETWORK AND METHOD FOR DRIVING THE SAME - A seed light module for a WDM-PON system is provided. The seed light module includes a reflector configured to reflect a part of seed light that is generated from a light source generator, and an optical attenuator configured to attenuate the intensity of the reflected seed light and provide the attenuated seed light, which corresponds to a signal generated by attenuating the intensity of the reflected seed light, to the light source generator. | 06-21-2012 |
20120163822 | APPARATUS AND METHOD FOR DRIVING WAVELENGTH-INDEPENDENT LIGHT SOURCE - An apparatus for driving a wavelength-independent light source is provided. The apparatus includes a seed light signal generation unit configured to generate seed light signals with one or more wavelengths based on a wavelength identification signal, a wavelength light detection unit configured to detect the wavelength identification signal from the seed light signals, an extraction unit configured to extract wavelength information corresponding to the detected wavelength identification signal and extract a driving condition of a wavelength-independent light source corresponding to the extracted wavelength information, and a driving unit configured to drive the wavelength-independent light source according to the extracted driving condition. | 06-28-2012 |
20130163629 | USER-SELECTABLE LASER AND OPTICAL TRANSMITTER HAVING THE SAME - Provided are a user-selectable laser and an optical transmitter including the same. The user-selectable laser is an external cavity laser including a semiconductor laser diode for outputting an optical signal, and a wavelength selection filter. The user-selectable laser may allow a user to select a wavelength selection filter which is optically coupled with the semiconductor laser diode and selectively causes oscillation at the wavelength of an optical signal output from the semiconductor laser diode. | 06-27-2013 |
20140199074 | ORTHOGONAL FREQUENCY DIVISION MULTIPLE ACCESS-PASSIVE OPTICAL NETWORK COMPRISING OPTICAL NETWORK UNIT AND OPTICAL LINE TERMINAL - An orthogonal frequency division multiple access-passive optical network including a plurality of optical network units each configured to generate orthogonal frequency division multiplexed signals, which are allocated thereto, based on a central frequency for frequency division multiplexing that is allocated in advance, and to use the generated signals in upstream transmission. | 07-17-2014 |
20140219659 | METHOD OF ALLOCATING UPSTREAM BANDWIDTH RESOURCE AND METHOD OF TRANSMITTING UPSTREAM DATA IN ORTHOGONAL FREQUENCY DIVISION MULTIPLE ACCESS-OPEN OPTICAL SUBSCRIBER NETWORK - There are provided a method of allocating upstream bandwidth resources and a method of transmitting upstream data in an orthogonal frequency division multiple access-open optical subscriber network. The method of allocating an upstream bandwidth resource according to an embodiment of the invention includes receiving queue status information from each optical network unit (ONU), and allocating an upstream bandwidth by providing to each ONU a 2-D upstream bandwidth map on a subcarrier-time resource through a frame synchronized at constant cycles, based on the queue status information received from each ONU. | 08-07-2014 |
20140219661 | METHOD OF SELECTING WAVELENGTH OF OPTICAL NETWORK UNIT IN PASSIVE OPTICAL NETWORK - Provided is a method of selecting a wavelength of an optical network unit including selecting a pre-loaded default wavelength as an available wavelength candidate or the wavelength that has been changed when a preset wavelength changing condition is satisfied as the available wavelength candidate, acquiring frame synchronization for a downstream signal having the same wavelength as the selected available wavelength candidate, and transmitting a registration request message to an optical line terminal (OLT) from which the downstream signal has been transmitted when the frame synchronization is acquired, assigning the available wavelength candidate to an available wavelength used for communication with the OLT and registering the terminal in the OLT when a registration allowance message is received from the OLT. | 08-07-2014 |
Patent application number | Description | Published |
20090220230 | Passive Optical Network Based On Reflective Semiconductor Optical Amplifier - Provided is a passive optical network (PON) based on a reflective semiconductor optical amplifier (RSOA). In the PON, seed-light-injection RSOAs are used in an optical line terminal (OLT) to achieve the color-less management of the wavelengths of OLT optic sources, and wavelength reuse RSOAs are used to achieve the color-less management of the wavelengths of ONTs. Therefore, problems related to ONT wavelength management can be eliminated by the wavelength reuse RSOAs, and problems related to OLT wavelength management can be eliminated by the seed-light-injection RSOAs. | 09-03-2009 |
20100014545 | ATHERMAL EXTERNAL CAVITY LASER - Provided is an athermal external cavity laser (ECL), whose output optical power and output wavelength can be kept regular irrespective of temperature changes without using additional temperature controlling components. The ECL comprises: a semiconductor amplifier; an optical fiber comprising a core in which a Bragg grating is formed and a cladding surrounding the core; and a thermosetting polymer that fixes the optical fiber to a ferrule and has a negative thermooptical coefficient, wherein the thickness of the cladding surrounding the core in which the Bragg grating is formed is smaller than the portion of the cladding surrounding the portion of the core where the Bragg grating is not formed, and the thermosetting polymer the negative thermooptical coefficient surrounds the cladding. The ECL does not need additional temperature controlling components and thus can be manufactured compact and at low cost, and thus can be used as a light source of a dense wavelength division multiplexing (DWDM) system in designing economical WDM passive optical networks (PON). | 01-21-2010 |
20110026923 | APPARATUS AND METHOD FOR OLT AND ONU FOR WAVELENGTH AGNOSTIC WAVELENGTH-DIVISION MULTIPLEXED PASSIVE OPTICAL NETWORKS - In a Wavelength-Division-Multiplexed Passive Optical Network (WDM-PON) utilizing a conventional downstream optical signal reusing method, there is an inventory problem that different optical transmitter types need to be provided for the operation, management, replacement, etc. of a system. A WDM-PON system according to the present invention, includes: a seed light (SL) unit generating a seed light whose wavelength intervals and center wavelengths are adjusted using at least one seed light source; an optical line terminal (OLT) receiving the wavelength-multiplexed seed light from the seed light unit, transmitting a downstream optical signal to a subscriber of the WDM-PON, and receiving a upstream optical signal from the subscriber; and an optical network unit (ONU) receiving the downstream optical signal from the OLT, flattening and modulating the downstream optical signal with upstream data so that the downstream optical signal is reused for carrying upstream data. It is possible to improve the quality and reliability of downstream transmission by sufficiently increasing an extinction ratio, and improve the quality and reliability of upstream transmission by sufficiently flattening an input downstream optical signal in a semiconductor optical amplifier. | 02-03-2011 |
Patent application number | Description | Published |
20080196927 | Working panel for multilayer printed circuit board - Disclosed is a working panel for a multilayer printed circuit board. The working panel for a multilayer printed circuit board is constructed in a manner such that first and second strips, having circuit layers and insulating layers which are layered on the upper and lower sides of a core in the opposite order with respect to each other, are appropriately disposed, by which the working panel can resist warpage due to thermal stress applied during the substrate fabrication process, thus imparting industrially useful effects that promise improvements in the standardization, productivity and yield of products. | 08-21-2008 |
20090085193 | Heat-releasing printed circuit board and semiconductor chip package - A heat-releasing printed circuit board and semiconductor chip package are disclosed. The heat-releasing printed circuit board includes an insulation layer, on a surface of which a circuit pattern is formed, and a solder resist, which is stacked on the insulation layer, where the solder resist contains carbon nanotubes. The heat-releasing printed circuit board allows the heat generated in a semiconductor chip to be dispersed in several directions of the board or package, to improve heat-releasing property. | 04-02-2009 |
20090087950 | Wafer packaging method - A wafer packaging method is disclosed. | 04-02-2009 |
20090184420 | Post bump and method of forming the same - A post bump and a method of forming the post bump are disclosed. The method of forming the post bump can include: forming a resist layer, in which an aperture is formed in correspondence to a position of an electrode pad, over a substrate, on which the electrode pad is formed; forming a metal post by filling a part of the aperture with a metallic material; filling a remaining part of the aperture with solder; reflowing the solder by applying heat; and removing the resist layer. This method can be utilized to prevent deviations in the plated solder and prevent the unnecessary flowing of the solder over the sides of the metal post during reflowing, so that the amount of solder used can be minimized. | 07-23-2009 |
20090283302 | Printed circuit board and manufacturing method thereof - Disclosed are a printed circuit board and a manufacturing method thereof. The printed circuit board in accordance with the present invention includes: a circuit laminate, a solder resist laminated on the circuit laminate, a metal support layer formed on the solder resist, a stiffener formed on the metal support layer. | 11-19-2009 |
20090297801 | Heat radiation substrate having metal core and method of manufacturing the same - Disclosed herein is a method of manufacturing a heat radiation substrate, including injection-molding mixed powder of carbon nanotubes and metal in a die to fabricate a metal core having through holes; molding the entire metal core including the through holes with an insulating resin to fabricate a metal core substrate; processing the insulating resin provided in the through holes to form connection holes; and forming a circuit pattern on the metal core substrate in which the connection holes are formed. | 12-03-2009 |
20100132982 | Package substrate including solder resist layer having pattern parts and method of fabricating the same - Disclosed is a package substrate including a solder resist layer having pattern parts and a method of fabricating the same, in which the pattern parts are formed on the solder resist layer, thus increasing heat dissipation efficiency and minimizing the warpage of the substrate. | 06-03-2010 |
20100163291 | SUBSTRATE EMBEDDED WITH PASSIVE DEVICE - A substrate embedded with a passive device, including a substrate, on which a cavity is formed; a passive device in the cavity, the passive being pre-molded; and a conductive material for adhering the passive device to the cavity, the conductive material being laminated on the cavity. | 07-01-2010 |
20110012261 | Post bump and method of forming the same - A post bump formed over an electrode pad of a substrate for electrically connecting to an external device, the post bump including a metal post formed over the electrode pad; and a solder formed over the metal post and shaped as a dome, the dome occupying a space defined by imaginary lines extending from a perimeter of the metal post along an axial direction of the metal post. | 01-20-2011 |
20110115121 | Method of manufacturing heat radiation substrate having metal core - A method of manufacturing a heat radiation substrate having a metal core, including injection-molding mixed powder of carbon nanotubes and metal in a die to fabricate a metal core having through holes; molding the entire metal core including the through holes with an insulating resin to fabricate a metal core substrate; processing the insulating resin provided in the through holes to form connection holes; and forming a circuit pattern on the metal core substrate in which the connection holes are formed. | 05-19-2011 |
20110182684 | MICRO DRILL AND METHOD OF FABRICATING THE SAME - A method of fabricating a micro drill, which includes a drill part for machining a hole and a shank part fixed to a motor, the drill part and the shank part being made of different materials. The method includes the steps of forming a drill part-forming powder compact having a recess in one end thereof, and forming a shank part-forming powder compact having a protrusion, the protrusion intended to be fitted into the recess of the drill part-forming powder compact, forming an assembly of the drill part-forming powder compact and the shank part-forming powder compact, with the protrusion fitted into the recess, and simultaneously sintering the assembly of the drill part-forming powder compact and the shank part-forming powder compact. | 07-28-2011 |