Class / Patent application number | Description | Number of patent applications / Date published |
398074000 | Hybrid | 28 |
20090016723 | Optical-wireless hybrid transmission system and optical-wireless hybrid transmission method - An optical transmitter of an optical-wireless hybrid transmission system according to the invention outputs a first single-mode optical signal (center frequency: f | 01-15-2009 |
20090060511 | COHERENT OPTICAL RECEIVER - A coherent optical receiver includes a 90-degree optical hybrid circuit to which a received signal light is input, I-channel and Q-channel photo detectors to which the outputs of the hybrid circuit are input, a clock extraction circuit which reproduces a clock whose speed is the same as a demodulated signal obtained by demodulating the received signal light and which is synchronized therewith, I-channel and Q-channel sampling circuits which sample the signal outputs from the I-channel and Q-channel photo detectors by use of the clock, and a digital signal processing section which digitally processes the sampled signals, converts them to a digital signal, and outputs the digital signal. The digital signal processing section feeds a phase offset signal detected there back to the clock extraction circuit to thereby control the phase of the clock, and compensates dispersion of light within a fiber and phase fluctuation during free-space propagation. | 03-05-2009 |
20090190926 | Combined phase and polarization modulation for optical communication - The invention relates to a modulation scheme for optical communication, in particular for fiber optics communication. According to invention, an optical signal is generated, both phase and polarization of which modulated in dependency of the data to be transmitted. Preferably, the generated optical signal comprises a sequence of symbols ( | 07-30-2009 |
20100221009 | Phase Chip Frequency-Bins Optical Code Division Multiple Access - Apparatus and system for transmitting and receiving optical code division multiple access data over an optical network. The apparatus comprises a spectral phase decoder for decoding the encoded optical signal to produce a decoded signal, a time gate for temporally extracting a user signal from the decoded signal, and a demodulator that is operable to extract user data from the user signal. The system preferably comprises a source for generating a sequence of optical pulses, each optical pulse comprising a plurality of spectral lines uniformly spaced in frequency so as to define a frequency bin, a data modulator associated with a subscriber and operable to modulate the sequence of pulses using subscriber data to produce a modulated data signals and a Hadamard encoder associated with the data modulator and operable to spectrally encode the modulated data signal to produce an encoded data signal. | 09-02-2010 |
20100310256 | PARALLEL OPTICAL RECEIVER FOR OPTICAL SYSTEMS - The present invention discloses a receiver for optical system, which provides improved performance due to implementation of multiple parallel analog-to-digital converters. Such configuration allows reducing the data speed processing thus improving bit-error-rate. Each channel of the WDM communications system consists of a set of orthogonal spectral bands. These bands are modulated via orthogonal frequency division multiplexing (OFDM) technique using M-PSK modulation format. At the receiver side, the incoming optical beam is split into a set of parallel branches. Each branch is mixed with a local oscillator beam having a spectrum within one sub-band of the WDM channel. In the preferred embodiment these beams are mixed in 90-degrees optical hybrid, which is followed by a set of balanced photodetectors. The baseband of each sub-band signal is converted into a digital signal using ADC. This allows the implementation of a series of lower-speed ADCs working in parallel instead of one high-speed ADC for the data recovery from the incoming optical signal. | 12-09-2010 |
20110243563 | Binary Modulation Node - Digital information can be carried on the fiber leg of an access network using binary modulation. Binary modulated data received at an O/E node can then be modulated onto an analog waveform using quadrature amplitude modulation or some other technique for modulating an analog waveform and transmitted over, for example, the coaxial leg of the network. The O/E node may also receive an analog signal, over the coaxial leg, modulated to carry upstream data from subscriber devices. The O/E node may demodulate the upstream signal to recover the upstream data and forward that upstream data over the fiber leg using a binary modulated optical signal. | 10-06-2011 |
20120263471 | OPTICAL OFDM TRANSMISSION HAVING A VARIABLE TRANSMISSION RATE - The present invention provides a method and system for transmitting data over an optical channel using OFDM with a variable transmission rate. Such method and system feeds an essentially constant transmission power over a predetermined OFDM bandwidth into the optical channel. In an embodiment, at least two OFDM subcarriers may be modulated with signal information derived from a single word of an OFDM symbol. Further thereto, the frequency spacing between the transmitted OFDM subcarriers may be changed. | 10-18-2012 |
20130077976 | TRANSMITTER AND METHOD FOR OPTICAL TRANSMISSION - An optical multi-wavelength transmitter comprising an optical interleaver with at least a first optical waveguide and a second optical waveguide; a first plurality of microcavity modulators coupled to the first optical waveguide and a second plurality of microcavity modulators coupled to the second waveguide. A plurality of optical wavelengths received at an input of the interleaver are separated into a first group of separated optical wavelengths for being input in the first optical waveguide and a second group of separated optical wavelengths for being input in the second optical waveguide. Each one of the first and the second group of separated optical wavelengths have a separated wavelength spacing between adjacent separated optical wavelengths. A method of optical multi-wavelength transmission is also disclosed. | 03-28-2013 |
20130272709 | OPTICAL FREQUENCY-DIVISION MULTIPLEXER, OPTICAL COMMUNICATION SYSTEM, AND OPTICAL FREQUENCY-DIVISION MULTIPLEXING METHOD - An optical frequency-division multiplexer includes: a first optical coupler configured to receive a first wavelength-division multiplexed light obtained by wavelength-division multiplexing a first carrier light and a first monitor light and split the first carrier light and the first monitor light from each other; an optical modulator configured to optically modulate the split first carrier light using a signal including a first data signal so as to multiplex the first data signal with the first carrier light; a receiver configured to receive a branched part of the split first monitor light and demodulate a second data signal from the first monitor light; and a second optical coupler configured to couple a remaining part of the split first monitor light and the first carrier light with which the first data signal has been multiplexed. | 10-17-2013 |
20140003817 | TRANSMIT AND RECEIVE MIMO PROTOCOLS FOR LIGHT ARRAY COMMUNICATIONS | 01-02-2014 |
20160080102 | Optimizing Optical Systems Using Code Division Multiple Access and/or Orthogonal Frequency-Division Multiplexing - An optical receiver comprises an optical port configured to receive an encoded optical signal, and a demodulation block indirectly coupled to the port and comprising a multiplexer, wherein the multiplexer is configured to receive an encoded electrical signal, wherein the encoded electrical signal is associated with the encoded optical signal, and wherein the encoded electrical signal is encoded using a code division multiple access (CDMA) scheme, receive a code associated with the scheme, perform a dot multiplication of the encoded electrical signal and the code, and generate a differential voltage based on the dot multiplication. | 03-17-2016 |
20160149661 | RF Sub-band De-Multiplexing for Ultra-Wide Band Optical Digital Coherent Detection - Systems and methods are disclosed for receiving data by radio frequency (RF) mixing to down-convert in-phase and quadrature parts of a photo-detected electrical RF band signal to baseband for data conversion; controlling a mixing phase of a electrical local oscillator (LO) at one or more RF mixing modules; selecting one of the RF sub-bands to be down-converted to baseband after coherent photo-detection; and performing RF sub-band de-multiplexing for ultra-wide band optical digital coherent detection. | 05-26-2016 |
398075000 | Time and wavelength division | 16 |
20080260385 | Signal processing apparatus and method for gigabit passive optical network - A signal processing apparatus for use in an optical line termination or optical network unit in a gigabit passive optical network encapsulates Ethernet signals, time-division multiplexed signals, and asynchronous transfer mode signals in the same way in a novel type of frame. The same input and output circuits can accordingly be used to support all three types of communication. A low-cost chip set including at least the input and output circuits of the apparatus can be combined with conversion circuits as necessary to provide a flexible answer to the needs of specific gigabit passive optical network systems. | 10-23-2008 |
20080298806 | Interleaving for 10G GPON - An apparatus comprising a plurality of data framers, a time division multiplexer coupled to the data framers, and an optical transmitter coupled to the time division multiplexer. Also disclosed is an apparatus comprising an optical receiver, a time division demultiplexer coupled to the optical receiver, and a data framer coupled to the time division demultiplexer. Also disclosed is an apparatus comprising at least one component configured to implement a method comprising combining a first plurality of data frames corresponding to a first plurality of channels into a first plurality of combined data frames using time division multiplexing and transmitting the first combined data frames over a single optical channel. | 12-04-2008 |
20090074414 | PORT-TO-PORT, NON-BLOCKING, SCALABLE OPTICAL ROUTER ARCHITECTURE AND METHOD FOR ROUTING OPTICAL TRAFFIC - Embodiments of the present invention provide an optical network and switch architecture that provides non-blocking routing from an ingress router to an egress router in the network on a port-to-port basis. The present invention provides routing for fixed and variable length optical data packets of varying types (including Internet Protocol (IP), data, voice, TDM, ATM, voice over data, etc.) at speeds from sub-Terabit per second (Tbps), to significantly in excess of Petabit per second (Pbps). The present invention includes the functionality of both large IP routers and optical cross-connects combined with a unique, non-blocking optical switching and routing techniques to obtain benefits in speed and interconnected capacity in a data transport network. The present invention can utilize a TWDM wave slot transport scheme in conjunction with a just-in-time scheduling pattern and a unique optical switch configuration that provides for non-blocking transport of data from ingress to egress. | 03-19-2009 |
20090169209 | Network system, optical line terminating apparatus, and optical network apparatus - A general object of the present invention is to provide an optical communication system in which an optical transmission power of an optical communication apparatus is controlled to be a required minimum power that apparatuses of all subscribers in the optical communication system meet a prescribed error rate. An optical line terminating apparatus (OLT) transmits data to multiple optical network apparatuses (ONUs) at an optical intensity calculated based on information acquired from the multiple ONUs, which is related to optical intensities of signals that the multiple ONUs receive from the OLT, the optical intensity being calculated so that a minimum optical intensity of the optical intensities of the signals is greater than a predetermined value. | 07-02-2009 |
20090317084 | PASSIVE OPTICAL NETWORK SYSTEM AND OPTICAL SIGNAL RECEIVING METHOD THEREOF - A passive optical network system includes: a plurality of optical signal splitter receiving optical signals from a plurality of optical network units (ONUs) to provide a plurality of upstream optical signals having different wavelengths; a hybrid optical filter multiplexing the plurality of upstream optical signals in a wavelength division multiplexing (WDM) scheme; and an optical line terminal (OLT) receiving the multiplexed upstream optical signals in a time division multiplexing (TDM) scheme. Therefore, the network system can be easily expanded when the number of subscribers increases, and the optical loss can be minimized. | 12-24-2009 |
20100021165 | OPTICAL TELECOMMUNICATIONS NETWORK AND METHOD - An optical communications network architecture and associated method which employs time and wavelength-interleaving for homing between nodes/satellites and hubs and for grooming, while employing wavelength-division-multiplexed wavelength circuits between hubs without requiring cross-connects or routers therebetween. | 01-28-2010 |
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 |
20100221010 | Encoding-decoding method, optical pulse time spreading apparatus, optical add-drop-multiplexer, and optical communication system - An optical pulse time spreading apparatus wherein an optical splitter divides an input optical pulse into first to U-th input optical pulses; first to U-th optical pulse time spreaders respectively have the first to U-th input optical pulses input thereto and output first to U-th chip pulse sequences each consisting of N chip pulses from a first to an N-th chip pulse arranged in order on a time axis into which the input optical pulse is time-spread; and an interval between adjacent ones of unit FBGs arranged in a p-th optical pulse time spreader and a Bragg reflection wavelength of the unit FBGs in the p-th optical pulse time spreader are set such that spectra of the first to U-th chip pulse sequences are different from each other. | 09-02-2010 |
20110033185 | TIME AND WAVELENGTH-SHIFTED DYNAMIC BIDIRECTIONAL SYSTEM - A bidirectional optical network, in which an incoming/downstream modulated optical signal(s) of a particular wavelength may carry content from a headend to a subscriber. An incoming/downstream unmodulated continuous wave optical signal(s) from the headend is time-shifted (i.e., time delayed with respect to just received incoming/downstream optical signal(s)), collected, modulated and sent back as return/upstream optical signal(s) from the subscriber to the headend. The return/upstream optical signal(s) may have the same wavelength or a slightly shifted wavelength relative to incoming/downstream optical signal(s). Wavelength, bandwidth, subscriber priority and service (content) provider may be fixed, dynamically, or statistically assigned. A modulated marker optical signal(s) is sent along with a modulated data optical signal simultaneously in a different plane. The modulated data optical signal(s) can therefore be securely delivered to a subscriber(s) according to the marker identification. Furthermore a device can be constructed from a group of components comprising an integrated tunable laser-modulator, a wavelength converter, a cyclic arrayed waveguide grating router, a photonic bandgap cyclic arrayed waveguide grating router, a burst enabled detector in order to electro-optically connect network elements, processors and chipsets on a printed circuit board. | 02-10-2011 |
20110069957 | METHOD AND APPARATUS FOR CHANNEL ALLOCATION IN A VISIBLE LIGHT COMMUNICATION SYSTEM - A method and apparatus for allocating resources of a Visible Light Communication (VLC) terminal in a VLC system. The VLC terminal receives a beacon message from a base station, coordinates time synchronization with the base station, searches for an available wavelength channel, constructs available wavelength channel information, and transmits an initial access request using a basic time slot channel and a basic wavelength channel. The base station considers the available wavelength channel information and a current channel allocation condition, allocates an appropriate channel, and transmits channel allocation information to the VLC terminal. The VLC terminal and the base station communicate data with each other using an allocated time slot channel included in the channel allocation information and an allocated wavelength channel included in the channel allocation information. | 03-24-2011 |
20120163819 | DATA TRANSMISSION APPARATUS AND METHOD FOR USE IN SEPARATE-TYPE BASE STATION - A data transmission apparatus for use in a separate-type base station is provided. The data transmission apparatus includes: a digital unit configured to generate first data that includes transmission method information indicating a selected transmission method and data to be transmitted; a time-division synchronization control unit configured to, in response to the selected transmission method being time-division multiplexing (TDM), generate second data by including synchronization information for transmitting the first data using TDM in the first data; and a wavelength conversion unit configured to convert at least one of the first data and the second data into one or more wavelength optical signals using a predefined wavelength or a predefined group of wavelengths and transmit the wavelength optical signals to one or more radio stations. | 06-28-2012 |
20130216230 | NETWORK DESIGN APPARATUS - Based on the demand information etc., an accommodation designing problem and an assignment problem are solved in a conventional method to design a network. It is confirmed whether or not a restriction on the number of wavelengths for each link is observed. When there are links exceeding the restriction of the number of wavelengths, the number of available wavelengths is subtracted from the first link having the largest number of excess wavelengths and the second link farthest from the first link in the links, and the result is set as a wavelength number limited value, thereby performing a network designing process again. | 08-22-2013 |
20130343759 | REPEATER FIBER-COAX UNITS - An optical-coax unit (OCU) includes an optical PHY to receive and transmit optical signals and a coax PHY to receive and transmit coax signals. The OCU also includes a media-independent interface to provide a first continuous bitstream from the optical PHY to the coax PHY and a second continuous bitstream from the coax PHY to the optical PHY. The first continuous bitstream corresponds to received optical signals and transmitted coax signals, and the second continuous bitstream corresponds to received coax signals and transmitted optical signals. | 12-26-2013 |
20140199072 | SYSTEM AND METHOD FOR NETWORK SYNCHRONIZATION AND FREQUENCY DISSEMINATION - Distribution of reference frequency and timing information in a network involves determining latency between a first and second node from time delay between transmission of a reference frequency and timing signal and reception of an optical return timing signal in response. In a network with pairs of first and second optical fibers in optical fiber connections between network nodes, for transmission of optical data signals separately in mutually opposite directions between the network nodes respectively, provisions are made to transmit the reference frequency and timing signal and the resulting optical return signal via the same fiber, one in the same direction as the unidirectional data signal over that fiber and the other upstream. Repeaters between the nodes may be modified to pass such signals upstream and downstream. In an embodiment wherein the network provides for an optical supervisory channel, the optical filters for combining the optical supervisory channel signal with the unidirectional data signal and separating the optical supervisory channel signal from the unidirectional data signal are used to combine and separate the reference frequency and timing signal and to pass the optical return timing signal. For this purpose, further optical filters may be added outside the main optical data channel to combine and separate the reference frequency and timing signal and the optical supervisory channel and to pass the optical return signal back to the filter that separates the optical supervisory channel signal from the data signal. | 07-17-2014 |
20150139651 | FLEXIBLE GRID TWDM-PON ARCHITECTURE AND INTELLIGENT SET-UP FOR TWDM-PON - An approach to proving a flexible grid architecture for time and wavelength division multiplexed passive optical networks is described. One embodiment includes an optical transmitter array configured to transmit an optical signal, an optical combiner coupled to the optical transmitter array configured to receive unlocked wavelengths from the optical transmitter array and output a single optical signal, and an optical amplifier coupled to the optical combiner configured to boost downstream optical power. In some embodiments, a WDM filter is coupled to the optical amplifier, and a tunable optical network units (ONUs) coupled to the WDM filter configured to transmit and receive the optical signals. In still other embodiments, a cyclic demultiplexer is coupled to the optical splitter and connects to an optical receiver array configured to receive optical signals. | 05-21-2015 |
20160065324 | ALL-OPTICAL REGENERATION SYSTEM FOR OPTICAL WAVELENGTH DIVISION MULTIPLEXED COMMUNICATION SYSTEMS - The invention relates to an all-optical regeneration system for regeneration of optical wavelength division multi-plexed WDM data signals in an optical WDM communication system. The system comprises a WDM-to-Optical time domain multi-plexing OTDM, WDM-to-OTDM, converter, capable of converting an input WDM data signal comprising multiple wavelength channels into an input OTDM data signal comprising multiple time multiplexed time channels. The system further comprises an all-optical regenerator unit being configured for regenerating the input OTDM data signal into an output OTDM data signal. The system additionally comprises an OTDM-to-WDM converter for converting the output OTDM data signal to an output WDM data signal. An input of the all-optical regenerator unit is in optical communication with an output of the WDM-to-OTDM converter, and an output of the all-optical regenerator unit is in optical communication with an input of the OTDM-to-WDM converter. The invention further relates to a method for all-optical regeneration of WDM data signals. | 03-03-2016 |