Communications & Networks
Communications Systems
The present invention relates to a SiP having reduced influence between a conductor and an antenna, and a method of designing the SiP. The SiP includes an antenna configured to function to transmit or receive data and mounted in the SiP to be integrated in the SiP, and a first planar conductor having at least one slit formed therein.
US 7835420 Orthogonal resource block hopping multiplexing method and apparatus
An orthogonal resource block hopping multiplexing (ORBHM) method and apparatus in a wired/wireless communication system in which a plurality of communication channels coexist in a single medium. The orthogonal resource block hopping multiplexing (ORBHM) communication system consists of a first communication station and a plurality of second…
US 7394548 Heterodyne laser interferometer using heterogenous mode helium-neon laser
In the method and a device for detecting the phase of a moving object using a heterodyne interferometer, a heterogeneous mode helium-neon laser is used as a direct light source to increase a measuring speed, a measuring resolution, and minimize the loss of the light source. Signals, which have only a frequency difference between reference signals…
An optical fiber, and an optical access network, a local area network and optical parts for communication, which uses the optical fiber, are disclosed. The optical fiber whose core diameter is 10 μm˜40 μm has at least two propagation modes in a wavelength over 1200 nm.
A communication recovering system for a wavelength division multiplexed passive optical network (WDM PON) includes a central office and remote nodes. When there is a fault in an optical fiber connecting a first blue/red band coupler to a blue/red band coupler R11, optical signals are inputted/outputted thereto/therefrom through a first 1×2…
US 6021237 All-fiber acousto-optic tunable filter
This invention relates to an all-fiber acousto-optic tunable wavelength filter which is useful in optical communications or optical fiber sensor systems. The present invention provides an all-fiber acousto-optic tunable filter, comprising: a length of optical fiber for propagating optical waves; a first mode converting means for selectively…
US 7920887 System and method for setting up P2P communication group in cellular system
Disclosed herein are a system and method for setting up a Peer-to-Peer (P2P) communication group in a cellular system, and a P2P communication system and method using the P2P communication group. The system for setting up a P2P communication group for a terminal in a cellular system including a base station and the terminals includes a location…
US 8054807 Handover method for mobile WiMAX network based on human mobility behavior
A Handover method in a mobile WiMAX network includes sending a list of target BSs for possible HO acquired by an MSS to a serving BS; providing, at the serving BS, a HO request to the target BSs in the list along with an unique identifier identifying the MSS to collect association responses from the target BSs; providing, at the serving BS, the…
US 6735391 Error correction and signal recovery in optical communications
The present invention relates to an automatic retrieval method of a wavelength-division multiplexed (WDM) ring network to the normal state after recovery of a failure. More specifically, the present invention relates to an automatic retrieval method of a WDM ring network to the normal state after recovery of a failure by inducing a lasing by…
US 6775050 Precision micromirror actuators for optical communications
Disclosed is a micromirror actuator that includes: a substrate provided with an insulating layer formed thereon; two lower columns spaced from each other by a designated distance, and formed on the insulating layer; a first torsion bar extending over upper surfaces of the lower columns; a second torsion bar formed so that the first and second…
US 6548806 Apparatus for Monitoring Frequency of WDM Signals Using Pilot Tone
An apparatus monitoring frequency of WDM signals using pilot tone and two interleaved solid etalon filters for efficient management and maintenance of wavelength division multiplexing optical transmission network is provided. Desirably, the apparatus for optical frequency monitoring includes splitting means, a plurality of optical filtering means,…
US 7369771 Optical network terminator and optical network connection method using it
An optical network terminator of the present invention includes an optical wavelength division multiplexer for receiving an optical signal and incoherent light. An optical detection unit converts a downstream high speed and low speed optical signals into electrical signals. A laser diode converts an upstream signal into an optical signal. A high…
US 7656347 Quadrature Radar Apparatus
A quadrature radar apparatus includes a quadrature signal generating unit, a plurality of coupler modules connected to the signal generating unit, an antenna unit receiving transmission signals from the coupler modules and a reception signal reflected from a target, one or more phase delay modules connected between one or more of the coupler…
US7835420 Orthogonal resource block hopping multiplexing method and apparatus
An orthogonal resource block hopping multiplexing (ORBHM) method and apparatus in a wired/wireless communication system in which a plurality of communication channels coexist in a single medium. The orthogonal resource block hopping multiplexing (ORBHM) communication system consists of a first communication station and a plurality of second…
US 6559984 Fiber Optic Network Path Monitoring
The present invention relates to an optical path monitoring device on the basis of the identification of input ports in optical cross-connect systems. An optical path monitoring apparatus in an optical cross-connect system is provided. The optical cross-connect system in accordance with the present invention includes input ports,…
US 6538784 Fiber Optic Network Switches and Routers
This invention relates to a multicast-capable optical cross-connect with layered modularity. Due to its layered modularity, this invention can be applied to many differently structured networks and provides easier maintenance than conventional optical cross-connects and efficient preparation for network evolution or node upgrade. By exploiting its…
US 7929963 Cognitive radio based air interface method in wireless communication system
A cognitive radio-based wireless communication system and an air interface method in a physical layer and a data link layer, which constitute a cognitive radio-based next-generation wireless communication system. The air interface method for wireless communication in the cognitive radio-based wireless communication system of the present invention…
A multi-phase ultra-wideband signal generator uses differential pulse oscillators. The multi-phase ultra-wideband signal generator using differential pulse oscillators includes N pulse oscillators for generating pulse signals based on a supply of power, and further comprises N inverting amplification units for outputting inverted amplified signals…
The present invention relates to an OPCPA apparatus. The OPCPA of the present invention includes an optical pulse stretcher for outputting chirped laser light using odd-order dispersion (third-order dispersion is mainly used). A pump laser outputs pump laser light. An OPA unit receives the pump laser light and the chirped laser light (signal),…
US 8022784 Planar transmission line-to-waveguide transition apparatus having an embedded bent stub
A wireless communication module includes a plurality of monolithic millimeter-wave integrated circuits (MMICs) for signal processing attached to the top surface of a multi-layer low temperature co-fired ceramic substrate; a planar transmission line formed on the top surface of the multi-layer substrate for communications between the MMICs; a metal…
US 8081061 Mobile RFID Reader and Method of Eliminating a Transmission Leakage Signal
A mobile radio-frequency identification (RFID) reader includes a high-frequency front-end unit including an antenna, a circulator, an output amplifier, and a signal processor chip. The signal processor chip includes a high-frequency transceiver, a pseudo-leakage signal generator configured to generate a pseudo-leakage signal based on a…
A resource allocation method in orthogonal frequency division multiple access wireless systems includes: setting, for each of terminals, data transmission factors including a resource location selection scheme; and determining, for each frame, locations of resources to be allocated to the terminals in a resource allocation order by using the…
US 8094547 Orthogonal Frequency and Code Hopping Multiplexing Communications Method
An Orthogonal Frequency and Code Hopping Multiplexing (OFCHM) communication method based Orthogonal Frequency Division Multiplexing (OFDM) in a wireless communication system in which a plurality of communication channels are synchronized through a single medium. Six types of spreading and hopping methods are included, a method of controlling…
US 8116628 Wavelength-division multiplexed passive optical network for embodying …
The present invention relates to a wavelength-division multiplexed passive optical network (WDM-PON) which embodies wavelength-independence of wavelength-locked Fabry Perot-Laser Diode (F-P LD). A WDM-PON of the present invention comprises an optical fiber being used for optical transmission to and from a broadband light source (BLS) with a low…
US 8169942 Method for wireless multi-hop network
Technology for a wireless multi-hop network is disclosed. a plurality of nodes in the wireless multi-hop network are synchronized to a period sequentially including a first interval and a second interval and are in an active state at the start time of the first interval. a node transmits a control frame at the start time of the first interval, the…
US 7397808 Parallel Switching Architecture for Multiple Input/Output
A multiple input/output-queued(MIOQ) switch is presented. This MIOQ switch comprises a (k,m)-dimensional crossbar fabric having k ingress lines and m egress lines; N input buffers at each input; M output buffers at each output; N×k interconnection networks each of which is able to move a packet from each input to one of the k egress lines; and…
The object of the present invention is to provide a wireless communication method and apparatus, which obtains both Multi-User Diversity (MUD) and Multi-User Multiplexing (MUM) effects simultaneously using multiple beams having random weights. In the wireless communication method, a transmission stage having M antennas (M is an integer equal to or…
A WLAN distributed/opportunistic scheduling (WDOS) method for acquiring a multi-user diversity gain is disclosed. The WDOS method allows a transmitter (i.e., a transmission user) to observe channel conditions of receivers (i.e., reception users), and commands the transmitter to transmit packets to a specific receiver having a relative good channel…
The invention relates to a multi-transmission/reception antenna device and a multi-transmission/reception method in a multi-user and multi-cell environment. When a plurality of spatial subchannels having a multi-user and a multi-transmission/reception antenna are allocated to users (that is, user terminals), a user group to be supported and the…
Multi-hop wireless networks have benefits in coverage extension and throughput improvement. In this multi-hop wireless networks, multiple channels are available to improve system performance through concurrent transmission. In this invention, a multi-channel assignment method is described. For efficient utilization of multiple channels considering…
US 7746837 Overhear-Based Transmitting Control System in WLANS
Thw overhear-based transmitting control system in WLANs to improve performance of 802.11 wireless LANs. The main invention of this scheme is that when the transmission of a node fails, one of neighboring nodes with better channel quality retransmits the lost frame in substitution. To do so, every node should maintain overhear table to buffer the…
An oceanographic observation buoy system using a wireless communication modem, and a method therefor. A separate wired communication cable is not required since data of the profile device and the buoy device is processed for exchange there etween using a wireless communication modem, so that a corresponding system can be quickly and simply…
A method for self configuration of wireless sensor network(WSN) based on the cluster tree structure, enables performance of large scale self configuration of WSN to improve.
A method for transmitting and receiving signal through avoiding same and different kind of interference signals in a same band of FHSS system, improves performance of wireless communication system, i.e., bluetooth.
A method for transmitting a signal while avoiding the influences of an interference signal in the same channel, temporarily transceive signals using a plurality of available transmission channels and determines the channel having a best link state as a transmission channel from among the plurality of used transmission channels and returns to an…
A method for transmitting a signal to multiple user terminals using multiple antennas in a radio communication system, which reduces the number of quantization bits without a decrease in the system capacity so that it is possible to reduce the amount of uplink feedback information or to enhance the performance of the system with the same number of…
PCT KR2011-001117 Multi Drop Bus System and Impedance Matching Method
The present invention provides the uniform transmission of power without excessive increase of resistance value for impedance matching.
US App 20120313450 Method and Apparatus for Transmitting Multi-Radio Power Using Time Division Mode
A multi-radio power transmission method, which wirelessly transmits power to each of at least one of the receivers using a time division mode in an exclusive power transmission time, so that it is possible to maintain high and uniform power transmission efficiency with respect to a plurality of receivers.
A method for transmitting beamforming in an orthogonal frequency division multiplexing (OFDM)-based MIMO wireless system, reduces the channel quantization error and feedback load, wherein a receiver estimates current channel information by using time and 2D channel correlation information of a frequency based on the previous channel information,…
A positioning system based on a radio communication apparatus including multiple antennas, which calculates a position of a terminal using only a single communication apparatus in which the multiple antennas are mounted, and calculates the position of the terminal more accurately by using two or more communication apparatuses.
Communication Technology
US 20130237155 A1 Mobile device digital communication and authentication methods
Embodiments of the present invention provide various approaches for mobile device intercommunication (e.g., digital) as well as various authentication methods. In one embodiment, the present invention provides direct line-of-sight visual digital communication between mobile devices for controlled security. In another embodiment, the present…
US 8256673 B1, US 8408462 B2 Time-varying barcode in an active display
Embodiments of the present invention provide time-varying barcodes(and graphs & images) in an active display for information exchange. Specifically, embodiments of the present invention provide a system and method for communicating information between electronic devices via a barcode image sequence. In a typical embodiment, a barcode image…
US 8231054 B1, US 8418922 B1, US 8561899 B2 Time-varying barcodes for information exchange
Embodiments of the present invention provide time-varying barcodes, (and graphs & images) for information exchange. Specifically, embodiments of the present invention provide a system and method for communicating information between electronic devices via a time-varying barcode image sequence. In a typical embodiment, information to be transmitted…
US 7650113 Apparatus for receiving wide-band pulse signal in communication channel
Disclosed herein is an apparatus for receiving a wide-band pulse signal in a communication channel using a human body. When a weak wide-band pulse signal, which is output from a communication channel using a human body as a data transmission medium, is restored to a digital signal, it is possible to accomplish low power consumption and high data…
Disclosed herein is a signal level conversion circuit for increasing the dynamic range of an Analog-to-Digital Converter (ADC). A comparison and calculation unit compares the value of an input signal Vin and the value of a first reference signal Vref1 and compares the value of the input signal Vin and the value of a second reference signal Vref2,…
US 7729587 Method of producing planar multimode optical waveguide using direct photopatterning
Disclosed is a method of producing a planar multimode optical waveguide by direct photo-patterning and, more particularly, to an optical waveguide material and a method of producing the same. It is possible to control the refractive index of the optical waveguide, and the optical waveguide has a desirable refractive index distribution throughout…
Disclosed herein is a flexible film optical waveguide, which is in flexible film form and includes upper and lower cladding layers, each of which is formed of an organic-inorganic hybrid material, and a core layer provided between the upper and lower cladding layers and formed of an organic-inorganic hybrid material having a refractive index…
The present invention relates to a SiP having reduced influence between a conductor and an antenna, and a method of designing the SiP. The SiP includes an antenna configured to function to transmit or receive data and mounted in the SiP to be integrated in the SiP, and a first planar conductor having at least one slit formed therein.
US 7835420 Orthogonal resource block hopping multiplexing method and apparatus
An orthogonal resource block hopping multiplexing (ORBHM) method and apparatus in a wired/wireless communication system in which a plurality of communication channels coexist in a single medium. The orthogonal resource block hopping multiplexing (ORBHM) communication system consists of a first communication station and a plurality of second…
US 7394548 Heterodyne laser interferometer using heterogenous mode helium-neon laser
In the method and a device for detecting the phase of a moving object using a heterodyne interferometer, a heterogeneous mode helium-neon laser is used as a direct light source to increase a measuring speed, a measuring resolution, and minimize the loss of the light source. Signals, which have only a frequency difference between reference signals…
An optical fiber, and an optical access network, a local area network and optical parts for communication, which uses the optical fiber, are disclosed. The optical fiber whose core diameter is 10 μm˜40 μm has at least two propagation modes in a wavelength over 1200 nm.
US 6021237 All-fiber acousto-optic tunable filter
This invention relates to an all-fiber acousto-optic tunable wavelength filter which is useful in optical communications or optical fiber sensor systems. The present invention provides an all-fiber acousto-optic tunable filter, comprising: a length of optical fiber for propagating optical waves; a first mode converting means for selectively…
The present invention relates to a passive optical network, which inexpensively improves the spectral efficiency of an access network and is capable of increasing the number of subscribers per channel by using WDM in combination with Time Division Multiplexing (TDM) or SubCarrier Multiple Access (SCMA) to expand a conventional WDM passive optical…
US 7936994 Broadband light source using fabry perot laser diodes
Disclosed is a broadband light source (BLS) necessary to implement wavelength-locked Fabry-Perot (FP) laser diodes (LDs) applicable to an optical subscriber network The BLS is based on a method using mutual injection of low-cost FP LDs and a method using FP LDs undergoing chirping. A power level of a light emitting diodes (LED), an erbium-doped…
US 7920887 System and method for setting up P2P communication group in cellular system
Disclosed herein are a system and method for setting up a Peer-to-Peer (P2P) communication group in a cellular system, and a P2P communication system and method using the P2P communication group. The system for setting up a P2P communication group for a terminal in a cellular system including a base station and the terminals includes a location…
US 8040964 Apparatus for receiving T-DMB signal and method of operating the same
There is provided an apparatus for receiving a T-DMB signal. The apparatus for receiving a T-DMB signal comprises an input buffer receiving and buffering a T-DMB signal comprising a null symbol and a phase reference symbol (PRS); an initial synchronizing unit estimating and compensating for time and frequency offsets of the T-DMB signal using the…
US 8054807 Handover method for mobile WiMAX network based on human mobility behavior
A Handover method in a mobile WiMAX network includes sending a list of target BSs for possible HO acquired by an MSS to a serving BS; providing, at the serving BS, a HO request to the target BSs in the list along with an unique identifier identifying the MSS to collect association responses from the target BSs; providing, at the serving BS, the…
US 6895185 Fiber optic networks
The present invention relates to an optical fiber access network, and more particularly, to a multi-purpose optical fiber access network capable of accepting all services provided by hybrid wireline/wireless access network.
US 6735391 Error correction and signal recovery in optical communications
The present invention relates to an automatic retrieval method of a wavelength-division multiplexed (WDM) ring network to the normal state after recovery of a failure. More specifically, the present invention relates to an automatic retrieval method of a WDM ring network to the normal state after recovery of a failure by inducing a lasing by…
US 6775050 Precision micromirror actuators for optical communications
Disclosed is a micromirror actuator that includes: a substrate provided with an insulating layer formed thereon; two lower columns spaced from each other by a designated distance, and formed on the insulating layer; a first torsion bar extending over upper surfaces of the lower columns; a second torsion bar formed so that the first and second…
US 6775058 Optical signal amplifiers
The present invention discloses a wide band optical amplifier with a common mid-stage device. In the wide band optical amplifier according to the present invention, the signals that enter the amplifier are first split into a couple of sub-band signals. The sub-band signals are amplified independently at different optical amplification sections,…
US 6526037 Signal decoding in CDMA systems
A method for allocating signature sequence used to distinguish my own signal from the other user’s signals in a code division multiple access system comprising the steps of obtaining and selecting a Park-Song sequence based upon a specific equations; allocating the selected Park-Song sequence as the signature sequence to the pertinent user;…
US 6021237 All-fiber acousto-optic tunable filter
This invention relates to an all-fiber acousto-optic tunable wavelength filter which is useful in optical communications or optical fiber sensor systems. The present invention provides an all-fiber acousto-optic tunable filter, comprising: a length of optical fiber for propagating optical waves…
US 6034770 Interferometric laser sensor having a linear laser cavity
An interferometer-type laser sensor acts concurrently as a light source and to measure external physical quantities such as rotation, magnetic field, current and fluid velocity. The interferometer-type laser sensor has a laser resonator having a laser gain medium, optical path and two or more reflectors to reflect incident light toward an opposite…
US 6253004 Optical interconnection structure for enlarging alignment tolerance
An optical interconnection structure between an optoelectric device and a single mode optical fiber for enlarging an alignment tolerance is provided. The optical interconnection structure is constituted by a microlensed optoelectric device and a graded index fiber ended single mode optical fiber.
US 6246811 Irreversible Optical Device Utilizing Optical Frequency Shift
An irreversible optical device using an optical frequency shift. The invention provides an irreversible phase shifter including frequency shifters. An irreversible interferometer is also provided which includes the irreversible phase shifter. The invention also provides an irreversible interferometer using a twin-mode optical fiber. In addition to…
US 6548806 Apparatus for Monitoring Frequency of WDM Signals Using Pilot Tone
An apparatus monitoring frequency of WDM signals using pilot tone and two interleaved solid etalon filters for efficient management and maintenance of wavelength division multiplexing optical transmission network is provided. Desirably, the apparatus for optical frequency monitoring includes splitting means, a plurality of optical filtering means,…
US 6947891 Efficient Speech Recognition System Bases on an Auditory Model
A speech recognition system that is insensitive to external noise and applicable to actual life includes an A/D converter that converts analog voice signals to digital signals. An FIR filtering section employs powers-of-two conversion to filter the digital signals converted at the A/D converter into numbers of channels. A characteristic extraction…
The present invention relates to a wavelength-division multiplexed passive optical network. In particular, it relates to a technology for minimizing the optical loss at a wavelength-division multiplexed passive optical network based on wavelength-locked light source Thereby it improves the transmission quality and increases the transmission…
US 7268027 Method of Manufacturing Photoreceiver
Disclosed is a method of manufacturing a photoreceiver, including sequentially laminating a buffer layer, a channel layer, a barrier layer, and a cap layer on a substrate; forming a mesa for HEMT and MSM PD by removing the buffer layer, the channel layer, the barrier layer, and the cap layer with the exception of a region corresponding to HEMT and…
US 7215656 Transmission and receiving using spreading modulation for spread spectrum
The present invention is related to a method and an apparatus for the orthogonal complex-domain spreading modulation in CDMA spread spectrum communication system when there are channels with statistically higher transmitting power. In CDMA spread spectrum communication systems with a transmitter and a receiver, the transmitter according to the…
US 7253945 Amplitude Dividing Type Laser Amplification Apparatus
An optical amplification apparatus includes a polarizing beam splitter for reflecting a portion of an incident light and transmitting a remaining portion of the incident light, depending upon a polarized state of the incident light, at least two optical amplification means each including a first polarizing plate which makes polarized states of the…
US 7369771 Optical network terminator and optical network connection method using it
An optical network terminator of the present invention includes an optical wavelength division multiplexer for receiving an optical signal and incoherent light. An optical detection unit converts a downstream high speed and low speed optical signals into electrical signals. A laser diode converts an upstream signal into an optical signal. A high…
US 7636365 Smart digital modules and smart digital wall surfaces combining the same
Disclosed are smart digital modules, a smart digital wall combining the smart digital modules, a context-aware interactive multimedia system, and an operating method thereof. The smart digital wall includes local coordinators for controlling the smart digital modules, and a coordination process for controlling the smart digital modules. The smart…
US 7656347 Quadrature Radar Apparatus
A quadrature radar apparatus includes a quadrature signal generating unit, a plurality of coupler modules connected to the signal generating unit, an antenna unit receiving transmission signals from the coupler modules and a reception signal reflected from a target, one or more phase delay modules connected between one or more of the coupler…
US 7684769 Data Communication Apparatus and Module Using Human Body
In circumstance of a wearable computing system, in order to effectively transfer data between electronic devices using electric property of human body, minimization, low power, and high-speed are required. Human body data communication apparatus and module using broadband signaling technology is provided to perform high-speed peer-to-peer data…
US 7835420 Orthogonal resource block hopping multiplexing method and apparatus
An orthogonal resource block hopping multiplexing (ORBHM) method and apparatus in a wired/wireless communication system in which a plurality of communication channels coexist in a single medium. The orthogonal resource block hopping multiplexing (ORBHM) communication system consists of a first communication station and a plurality of second…
US 7106974 Low-cost WDM Source with an Incoherent Light Injected Fabry-Perot Laser Diode
The present invention discloses a low-cost light source for optical transmission systems and optical networks based on wavelength-division multiplexing (WDM) technology. A light source in accordance with the present invention is implemented by externally injecting a narrow-band incoherent light into a Fabry-Perot laser diode (F-P LD). After…
US 6559984 Fiber Optic Network Path Monitoring
The present invention relates to an optical path monitoring device on the basis of the identification of input ports in optical cross-connect systems. An optical path monitoring apparatus in an optical cross-connect system is provided. The optical cross-connect system in accordance with the present invention includes input ports,…
US 6538784 Fiber Optic Network Switches and Routers
This invention relates to a multicast-capable optical cross-connect with layered modularity. Due to its layered modularity, this invention can be applied to many differently structured networks and provides easier maintenance than conventional optical cross-connects and efficient preparation for network evolution or node upgrade. By exploiting its…
An apparatus for measuring the wavelength, optical power, and an optical signal-to-noise ratio (OSNR) of each optical signal in wavelength-division-multiplexing optical communication includes: elements for splitting a part of wavelength-division-multiplexed (WDM) signals, elements for amplifying the WDM signals and generating spontaneous emission…
US 6188509 Simple bidirectional add/drop amplifier module based on a single multiplexer
This invention is to construct a bidirectional WDM add/drop amplifier module for transmitting WDMS in bidirection and for adding/dropping a signal in bidirection at each node in a WDM network system using a single N.times.N multiplexer. The bidirectional WDM add/drop amplifier module comprises an 8.times.8 arrayed-waveguide grating. The 8.times.8…
A multi-phase ultra-wideband signal generator uses differential pulse oscillators. The multi-phase ultra-wideband signal generator using differential pulse oscillators includes N pulse oscillators for generating pulse signals based on a supply of power, and further comprises N inverting amplification units for outputting inverted amplified signals…
US 8009350 Laptop-size high-order harmonic generation apparatus using near field Enhancement
Disclosed herein is a laptop-size high-order harmonic generation apparatus using near field enhancement. The laptop-size high-order harmonic generation apparatus using near field enhancement includes a femtosecond laser generator, light transfer means for transferring light output from the femtosecond laser generator, micro patterns formed of…
US 7964944 System on Package of a Mobile RFID Interrogator
The present invention is to implement a SOP of a mobile RFID interrogator. The substrate has external connection terminal patterns on a first surface of a substrate and circuit wiring patterns on a second surface of the substrate. a high frequency front-end part, a power amplifier IC, an analog-digital signal processing chip and the like are…
The present invention relates to an OPCPA apparatus. The OPCPA of the present invention includes an optical pulse stretcher for outputting chirped laser light using odd-order dispersion (third-order dispersion is mainly used). A pump laser outputs pump laser light. An OPA unit receives the pump laser light and the chirped laser light (signal),…
US 8022784 Planar transmission line-to-waveguide transition apparatus having an embedded bent stub
A wireless communication module includes a plurality of monolithic millimeter-wave integrated circuits (MMICs) for signal processing attached to the top surface of a multi-layer low temperature co-fired ceramic substrate; a planar transmission line formed on the top surface of the multi-layer substrate for communications between the MMICs; a metal…
The present invention relates to an optical modulation method and optical modulation system of a wavelength locked Fabry Perot-Laser Diode (FP-LD) by injecting a broadband light source (BLS) using mutual injection of FP-LDs. More specifically, the present invention relates to a novel modulation technology which embodies a wavelength locked FP-LD…
The present invention discloses a wavelength-division multiplexing passive optical network (WDM-PON) capable of high-bandwidth transmission for optical signals by using modulation format having high spectral efficiency. The WDM-PON according to the present invention provides a larger capacity and higher bandwidth transmission economically (at…
US 8081061 Mobile RFID Reader and Method of Eliminating a Transmission Leakage Signal
A mobile radio-frequency identification (RFID) reader includes a high-frequency front-end unit including an antenna, a circulator, an output amplifier, and a signal processor chip. The signal processor chip includes a high-frequency transceiver, a pseudo-leakage signal generator configured to generate a pseudo-leakage signal based on a…
A resource allocation method in orthogonal frequency division multiple access wireless systems includes: setting, for each of terminals, data transmission factors including a resource location selection scheme; and determining, for each frame, locations of resources to be allocated to the terminals in a resource allocation order by using the…
US 8094547 Orthogonal Frequency and Code Hopping Multiplexing Communications Method
An Orthogonal Frequency and Code Hopping Multiplexing (OFCHM) communication method based Orthogonal Frequency Division Multiplexing (OFDM) in a wireless communication system in which a plurality of communication channels are synchronized through a single medium. Six types of spreading and hopping methods are included, a method of controlling…
The present invention relates to a wavelength-division multiplexed passive optical network (WDM-PON) which embodies wavelength-independence of wavelength-locked Fabry Perot-Laser Diode (F-P LD). A WDM-PON of the present invention comprises an optical fiber being used for optical transmission to and from a broadband light source (BLS) with a low…
A method and apparatus for generating and measuring a torsional wave in a rod, shaft or pipe using magnetostriction are provided. The magnetostrictive transducer includes at least one strip attached to a predetermined position of a rod member, an insulator disposed around the strip, a coil wound around the insulator, and magnets providing a bias…
The present invention relates to a method for estimating an optimized transmission bit rate in a wireless local area network (LAN) system, which is to provide an accurate data transmission bit rate according to channel status when block data are transmitted in the wireless LAN system. According to the present invention, there is provided a method…
US 8169942 Method for wireless multi-hop network
Technology for a wireless multi-hop network is disclosed. a plurality of nodes in the wireless multi-hop network are synchronized to a period sequentially including a first interval and a second interval and are in an active state at the start time of the first interval. a node transmits a control frame at the start time of the first interval, the…
US 6765534 Mechanical Beam Steering Antenna and Fabricating Method thereof
The present invention is concerning an element antenna to construct an efficient antenna system, which is able to control mechanical movement of micro-strip patch antenna and to control electrical phase of signal. The movement of an element antenna is come from movement of a platform on which the element antenna is formed. The platform is made of…
US 7397808 Parallel Switching Architecture for Multiple Input/Output
A multiple input/output-queued(MIOQ) switch is presented. This MIOQ switch comprises a (k,m)-dimensional crossbar fabric having k ingress lines and m egress lines; N input buffers at each input; M output buffers at each output; N×k interconnection networks each of which is able to move a packet from each input to one of the k egress lines; and…
The object of the present invention is to provide a wireless communication method and apparatus, which obtains both Multi-User Diversity (MUD) and Multi-User Multiplexing (MUM) effects simultaneously using multiple beams having random weights. In the wireless communication method, a transmission stage having M antennas (M is an integer equal to or…
US 7526047 Method for encoding a message into geometrically uniform space-time trellis codes
A method for coding messages by group codes over label alphabet and H-symmetric labeling is provided in order to encode geometrically uniform space-time trellis codes considering a distance spectrum. The coding method makes the complexity of code searching reduced considerably by limiting the object of the code design to geometrically uniform…
US 7433423 Multiple Trellis Coded Differential Unitary Space-time Modulation
A method of differential unitary space-time modulation is provided by encoding messages to transmit through multiple transmitting antenna into multiple trellis code in a communication system wherein the signals are transmitted between multiple transmitting antennas and at least one receive antenna. The performance provided is superior to that of…
US 7492808 Decoding method using adaptive step-size algorithm for a space-time coded DS-CDMA system
Disclosed is a method for decoding received signals on communication channels between at least one transmit antenna and plural receive antennas in a space-time coded direct sequence (DS)-CDMA communication system. The decoding method includes steps of: adjusting the step-size which is an update unit for the tap weight vector for…
Disclosed is a method for encoding messages with space-time trellis codes(STTC) and transmitting the encoded messages in communication system provided with at least two transmit antennas and at least one receive antenna. The method comprising generating a codeword by encoding message using STTC; generating a modified codeword by multiplying the…
An apparatus and a method for transmission encoding a message with space-time turbo code using feedback information of the channel gain or the phase in digital mobile communication system having a plurality of transmit antennas are disclosed.
A WLAN distributed/opportunistic scheduling (WDOS) method for acquiring a multi-user diversity gain is disclosed. The WDOS method allows a transmitter (i.e., a transmission user) to observe channel conditions of receivers (i.e., reception users), and commands the transmitter to transmit packets to a specific receiver having a relative good channel…
The invention relates to a multi-transmission/reception antenna device and a multi-transmission/reception method in a multi-user and multi-cell environment. When a plurality of spatial subchannels having a multi-user and a multi-transmission/reception antenna are allocated to users (that is, user terminals), a user group to be supported and the…
Multi-hop wireless networks have benefits in coverage extension and throughput improvement. In this multi-hop wireless networks, multiple channels are available to improve system performance through concurrent transmission. In this invention, a multi-channel assignment method is described. For efficient utilization of multiple channels considering…
US 7746837 Overhear-Based Transmitting Control System in WLANS
The overhear-based transmitting control system in WLANs to improve performance of 802.11 wireless LANs. The main invention of this scheme is that when the transmission of a node fails, one of neighboring nodes with better channel quality retransmits the lost frame in substitution. To do so, every node should maintain overhear table to buffer the…
An oceanographic observation buoy system using a wireless communication modem, and a method therefor. A separate wired communication cable is not required since data of the profile device and the buoy device is processed for exchange there etween using a wireless communication modem, so that a corresponding system can be quickly and simply…
A method for self configuration of wireless sensor network(WSN) based on the cluster tree structure, enables performance of large scale self configuration of WSN to improve.
A method for transmitting and receiving signal through avoiding same and different kind of interference signals in a same band of FHSS system, improves performance of wireless communication system, i.e., bluetooth.
A method for transmitting a signal while avoiding the influences of an interference signal in the same channel, temporarily transceive signals using a plurality of available transmission channels and determines the channel having a best link state as a transmission channel from among the plurality of used transmission channels and returns to an…
PCT KR2011-004544 Method and Apparatus for Resource Allocation in a Virtual Network
A method for resource allocation in a virtual network of a resource allocation device, sets the path and allocates the bandwidth, that the method is suitable for reducing waste of unnecessary resources and efficiency of network.
A method for transmitting a signal to multiple user terminals using multiple antennas in a radio communication system, which reduces the number of quantization bits without a decrease in the system capacity so that it is possible to reduce the amount of uplink feedback information or to enhance the performance of the system with the same number of…
PCT KR2011-001117 Multi Drop Bus System and Impedance Matching Method
The present invention provides the uniform transmission of power without excessive increase of resistance value for impedance matching.
US App 20120313450 Method and Apparatus for Transmitting Multi-Radio Power Using Time Division Mode
A multi-radio power transmission method, which wirelessly transmits power to each of at least one of the receivers using a time division mode in an exclusive power transmission time, so that it is possible to maintain high and uniform power transmission efficiency with respect to a plurality of receivers.
A method for transmitting beamforming in an orthogonal frequency division multiplexing (OFDM)-based MIMO wireless system, reduces the channel quantization error and feedback load, wherein a receiver estimates current channel information by using time and 2D channel correlation information of a frequency based on the previous channel information,…
A method for estimating a channel using a dedicated pilot signal in an OFDM-based wireless communication system using a transmission beamforming technique and a multi- antenna transmission technique, which can minimize channel estimation errors and can maximize a throughput of a system by adaptively determining an optimum dedicated pilot pat
Fiber
US 7729587 Method of producing planar multimode optical waveguide using direct photopatterning
Disclosed is a method of producing a planar multimode optical waveguide by direct photo-patterning and, more particularly, to an optical waveguide material and a method of producing the same. It is possible to control the refractive index of the optical waveguide, and the optical waveguide has a desirable refractive index distribution throughout…
Disclosed herein is a flexible film optical waveguide, which is in flexible film form and includes upper and lower cladding layers, each of which is formed of an organic-inorganic hybrid material, and a core layer provided between the upper and lower cladding layers and formed of an organic-inorganic hybrid material having a refractive index…
US 7394548 Heterodyne laser interferometer using heterogenous mode helium-neon laser
In the method and a device for detecting the phase of a moving object using a heterodyne interferometer, a heterogeneous mode helium-neon laser is used as a direct light source to increase a measuring speed, a measuring resolution, and minimize the loss of the light source. Signals, which have only a frequency difference between reference signals…
An optical fiber, and an optical access network, a local area network and optical parts for communication, which uses the optical fiber, are disclosed. The optical fiber whose core diameter is 10 μm˜40 μm has at least two propagation modes in a wavelength over 1200 nm.
A communication recovering system for a wavelength division multiplexed passive optical network (WDM PON) includes a central office and remote nodes. When there is a fault in an optical fiber connecting a first blue/red band coupler to a blue/red band coupler R11, optical signals are inputted/outputted thereto/therefrom through a first 1×2…
US 6021237 All-fiber acousto-optic tunable filter
This invention relates to an all-fiber acousto-optic tunable wavelength filter which is useful in optical communications or optical fiber sensor systems. The present invention provides an all-fiber acousto-optic tunable filter, comprising: a length of optical fiber for propagating optical waves; a first mode converting means for selectively…
The present invention relates to a passive optical network, which inexpensively improves the spectral efficiency of an access network and is capable of increasing the number of subscribers per channel by using WDM in combination with Time Division Multiplexing (TDM) or SubCarrier Multiple Access (SCMA) to expand a conventional WDM passive optical…
US 7936994 Broadband light source using fabry perot laser diodes
Disclosed is a broadband light source (BLS) necessary to implement wavelength-locked Fabry-Perot (FP) laser diodes (LDs) applicable to an optical subscriber network The BLS is based on a method using mutual injection of low-cost FP LDs and a method using FP LDs undergoing chirping. A power level of a light emitting diodes (LED), an erbium-doped…
US 6895185 Fiber optic networks
The present invention relates to an optical fiber access network, and more particularly, to a multi-purpose optical fiber access network capable of accepting all services provided by hybrid wireline/wireless access network.
US 6735391 Error correction and signal recovery in optical communications
The present invention relates to an automatic retrieval method of a wavelength-division multiplexed (WDM) ring network to the normal state after recovery of a failure. More specifically, the present invention relates to an automatic retrieval method of a WDM ring network to the normal state after recovery of a failure by inducing a lasing by…
US 6775050 Precision micromirror actuators for optical communications
Disclosed is a micromirror actuator that includes: a substrate provided with an insulating layer formed thereon; two lower columns spaced from each other by a designated distance, and formed on the insulating layer; a first torsion bar extending over upper surfaces of the lower columns; a second torsion bar formed so that the first and second…
US 6775058 Optical signal amplifiers
The present invention discloses a wide band optical amplifier with a common mid-stage device. In the wide band optical amplifier according to the present invention, the signals that enter the amplifier are first split into a couple of sub-band signals. The sub-band signals are amplified independently at different optical amplification sections,…
US 6021237 All-fiber acousto-optic tunable filter
This invention relates to an all-fiber acousto-optic tunable wavelength filter which is useful in optical communications or optical fiber sensor systems. The present invention provides an all-fiber acousto-optic tunable filter, comprising: a length of optical fiber for propagating optical waves…
US 6034770 Interferometric laser sensor having a linear laser cavity
An interferometer-type laser sensor acts concurrently as a light source and to measure external physical quantities such as rotation, magnetic field, current and fluid velocity. The interferometer-type laser sensor has a laser resonator having a laser gain medium, optical path and two or more reflectors to reflect incident light toward an opposite…
US 6253004 Optical interconnection structure for enlarging alignment tolerance
An optical interconnection structure between an optoelectric device and a single mode optical fiber for enlarging an alignment tolerance is provided. The optical interconnection structure is constituted by a microlensed optoelectric device and a graded index fiber ended single mode optical fiber.
US 6246811 Irreversible Optical Device Utilizing Optical Frequency Shift
An irreversible optical device using an optical frequency shift. The invention provides an irreversible phase shifter including frequency shifters. An irreversible interferometer is also provided which includes the irreversible phase shifter. The invention also provides an irreversible interferometer using a twin-mode optical fiber. In addition to…
US 6548806 Apparatus for Monitoring Frequency of WDM Signals Using Pilot Tone
An apparatus monitoring frequency of WDM signals using pilot tone and two interleaved solid etalon filters for efficient management and maintenance of wavelength division multiplexing optical transmission network is provided. Desirably, the apparatus for optical frequency monitoring includes splitting means, a plurality of optical filtering means,…
The present invention relates to a wavelength-division multiplexed passive optical network. In particular, it relates to a technology for minimizing the optical loss at a wavelength-division multiplexed passive optical network based on wavelength-locked light source Thereby it improves the transmission quality and increases the transmission…
US 7268027 Method of Manufacturing Photoreceiver
Disclosed is a method of manufacturing a photoreceiver, including sequentially laminating a buffer layer, a channel layer, a barrier layer, and a cap layer on a substrate; forming a mesa for HEMT and MSM PD by removing the buffer layer, the channel layer, the barrier layer, and the cap layer with the exception of a region corresponding to HEMT and…
US 7253945 Amplitude Dividing Type Laser Amplification Apparatus
An optical amplification apparatus includes a polarizing beam splitter for reflecting a portion of an incident light and transmitting a remaining portion of the incident light, depending upon a polarized state of the incident light, at least two optical amplification means each including a first polarizing plate which makes polarized states of the…
US 7369771 Optical network terminator and optical network connection method using it
An optical network terminator of the present invention includes an optical wavelength division multiplexer for receiving an optical signal and incoherent light. An optical detection unit converts a downstream high speed and low speed optical signals into electrical signals. A laser diode converts an upstream signal into an optical signal. A high…
US 7106974 Low-cost WDM Source with an Incoherent Light Injected Fabry-Perot Laser Diode
The present invention discloses a low-cost light source for optical transmission systems and optical networks based on wavelength-division multiplexing (WDM) technology. A light source in accordance with the present invention is implemented by externally injecting a narrow-band incoherent light into a Fabry-Perot laser diode (F-P LD). After…
US 6538784 Fiber Optic Network Switches and Routers
This invention relates to a multicast-capable optical cross-connect with layered modularity. Due to its layered modularity, this invention can be applied to many differently structured networks and provides easier maintenance than conventional optical cross-connects and efficient preparation for network evolution or node upgrade. By exploiting its…
US 6396574 Apparatus for measuring the wavelength, optical power and optical signal-to …
An apparatus for measuring the wavelength, optical power, and an optical signal-to-noise ratio (OSNR) of each optical signal in wavelength-division-multiplexing optical communication includes: elements for splitting a part of wavelength-division-multiplexed (WDM) signals, elements for amplifying the WDM signals and generating spontaneous emission…
US 6188509 Simple bidirectional add/drop amplifier module based on a single multiplexer
This invention is to construct a bidirectional WDM add/drop amplifier module for transmitting WDMS in bidirection and for adding/dropping a signal in bidirection at each node in a WDM network system using a single N.times.N multiplexer. The bidirectional WDM add/drop amplifier module comprises an 8.times.8 arrayed-waveguide grating. The 8.times.8…
The present invention relates to an optical modulation method and optical modulation system of a wavelength locked Fabry Perot-Laser Diode (FP-LD) by injecting a broadband light source (BLS) using mutual injection of FP-LDs. More specifically, the present invention relates to a novel modulation technology which embodies a wavelength locked FP-LD…
The present invention discloses a wavelength-division multiplexing passive optical network (WDM-PON) capable of high-bandwidth transmission for optical signals by using modulation format having high spectral efficiency. The WDM-PON according to the present invention provides a larger capacity and higher bandwidth transmission economically (at…
Telecommunications
US 7729587 Method of producing planar multimode optical waveguide using direct photopatterning
Disclosed is a method of producing a planar multimode optical waveguide by direct photo-patterning and, more particularly, to an optical waveguide material and a method of producing the same. It is possible to control the refractive index of the optical waveguide, and the optical waveguide has a desirable refractive index distribution throughout…
The present invention relates to a SiP having reduced influence between a conductor and an antenna, and a method of designing the SiP. The SiP includes an antenna configured to function to transmit or receive data and mounted in the SiP to be integrated in the SiP, and a first planar conductor having at least one slit formed therein.
US 7835420 Orthogonal resource block hopping multiplexing method and apparatus
An orthogonal resource block hopping multiplexing (ORBHM) method and apparatus in a wired/wireless communication system in which a plurality of communication channels coexist in a single medium. The orthogonal resource block hopping multiplexing (ORBHM) communication system consists of a first communication station and a plurality of second…
US 7394548 Heterodyne laser interferometer using heterogenous mode helium-neon laser
In the method and a device for detecting the phase of a moving object using a heterodyne interferometer, a heterogeneous mode helium-neon laser is used as a direct light source to increase a measuring speed, a measuring resolution, and minimize the loss of the light source. Signals, which have only a frequency difference between reference signals…
A communication recovering system for a wavelength division multiplexed passive optical network (WDM PON) includes a central office and remote nodes. When there is a fault in an optical fiber connecting a first blue/red band coupler to a blue/red band coupler R11, optical signals are inputted/outputted thereto/therefrom through a first 1×2…
The present invention relates to a passive optical network, which inexpensively improves the spectral efficiency of an access network and is capable of increasing the number of subscribers per channel by using WDM in combination with Time Division Multiplexing (TDM) or SubCarrier Multiple Access (SCMA) to expand a conventional WDM passive optical…
US 8054807 Handover method for mobile WiMAX network based on human mobility behavior
A Handover method in a mobile WiMAX network includes sending a list of target BSs for possible HO acquired by an MSS to a serving BS; providing, at the serving BS, a HO request to the target BSs in the list along with an unique identifier identifying the MSS to collect association responses from the target BSs; providing, at the serving BS, the…
US 6775050 Precision micromirror actuators for optical communications
Disclosed is a micromirror actuator that includes: a substrate provided with an insulating layer formed thereon; two lower columns spaced from each other by a designated distance, and formed on the insulating layer; a first torsion bar extending over upper surfaces of the lower columns; a second torsion bar formed so that the first and second…
US 6526037 Signal decoding in CDMA systems
A method for allocating signature sequence used to distinguish my own signal from the other user’s signals in a code division multiple access system comprising the steps of obtaining and selecting a Park-Song sequence based upon a specific equations; allocating the selected Park-Song sequence as the signature sequence to the pertinent user;…
The present invention relates to a wavelength-division multiplexed passive optical network. In particular, it relates to a technology for minimizing the optical loss at a wavelength-division multiplexed passive optical network based on wavelength-locked light source Thereby it improves the transmission quality and increases the transmission…
US 7835420 Orthogonal resource block hopping multiplexing method and apparatus
An orthogonal resource block hopping multiplexing (ORBHM) method and apparatus in a wired/wireless communication system in which a plurality of communication channels coexist in a single medium. The orthogonal resource block hopping multiplexing (ORBHM) communication system consists of a first communication station and a plurality of second…
The present invention discloses a wavelength-division multiplexing passive optical network (WDM-PON) capable of high-bandwidth transmission for optical signals by using modulation format having high spectral efficiency. The WDM-PON according to the present invention provides a larger capacity and higher bandwidth transmission economically (at…
A WLAN distributed/opportunistic scheduling (WDOS) method for acquiring a multi-user diversity gain is disclosed. The WDOS method allows a transmitter (i.e., a transmission user) to observe channel conditions of receivers (i.e., reception users), and commands the transmitter to transmit packets to a specific receiver having a relative good channel…
US 7746837 Overhear-Based Transmitting Control System in WLANS
Thw overhear-based transmitting control system in WLANs to improve performance of 802.11 wireless LANs. The main invention of this scheme is that when the transmission of a node fails, one of neighboring nodes with better channel quality retransmits the lost frame in substitution. To do so, every node should maintain overhear table to buffer the…
A method for self configuration of wireless sensor network(WSN) based on the cluster tree structure, enables performance of large scale self configuration of WSN to improve.
A method for transmitting and receiving signal through avoiding same and different kind of interference signals in a same band of FHSS system, improves performance of wireless communication system, i.e., bluetooth.
US App 20120313450 Method and Apparatus for Transmitting Multi-Radio Power Using Time Division Mode
A multi-radio power transmission method, which wirelessly transmits power to each of at least one of the receivers using a time division mode in an exclusive power transmission time, so that it is possible to maintain high and uniform power transmission efficiency with respect to a plurality of receivers.
A method for transmitting beamforming in an orthogonal frequency division multiplexing (OFDM)-based MIMO wireless system, reduces the channel quantization error and feedback load, wherein a receiver estimates current channel information by using time and 2D channel correlation information of a frequency based on the previous channel informatio
Telephony
US 6526037 Signal decoding in CDMA systems
A method for allocating signature sequence used to distinguish my own signal from the other user’s signals in a code division multiple access system comprising the steps of obtaining and selecting a Park-Song sequence based upon a specific equations; allocating the selected Park-Song sequence as the signature sequence to the pertinent user;…
US 6947891 Efficient Speech Recognition System Bases on an Auditory Model
A speech recognition system that is insensitive to external noise and applicable to actual life includes an A/D converter that converts analog voice signals to digital signals. An FIR filtering section employs powers-of-two conversion to filter the digital signals converted at the A/D converter into numbers of channels. A characteristic extraction…
The object of the present invention is to provide a wireless communication method and apparatus, which obtains both Multi-User Diversity (MUD) and Multi-User Multiplexing (MUM) effects simultaneously using multiple beams having random weights. In the wireless communication method, a transmission stage having M antennas (M is an integer equal to or…
US 7433423 Multiple Trellis Coded Differential Unitary Space-time Modulation
A method of differential unitary space-time modulation is provided by encoding messages to transmit through multiple transmitting antenna into multiple trellis code in a communication system wherein the signals are transmitted between multiple transmitting antennas and at least one receive antenna. The performance provided is superior to that of…
A method for transmitting and receiving signal through avoiding same and different kind of interference signals in a same band of FHSS system, improves performance of wireless communication system, i.e., blueto
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