Class / Patent application number | Description | Number of patent applications / Date published |
398099000 | Multiple access (e.g., TDMA, CSMA) | 8 |
20090190931 | OPTICAL LINE TERMINAL - An optical line terminal receives an optical signal transmitted by time division multiple access from plural optical network units among which are an optical network unit performing communications at a first bit rate and an optical network unit performing communications at a second bit rate. The optical line terminal includes a branching unit, a first receiving unit, and a second receiving unit. The branching unit branches the optical signal into branches, at an asymmetrical branching ratio. The first receiving unit receives a branch having the first bit rate, among the branches of a greater branched proportion. The second receiving unit receives a branch having the second bit rate, among the branches of a lesser branched proportion. | 07-30-2009 |
20100014866 | Digital Automatic Gain Control Apparatus and Method in Burst Mode Optical Receiver - A transimpedance amplifier for a burst mode optical communication converts a burst current signal into differential output voltage signals. Using a multi-level digital AGC mechanism, the transimpedance amplifier is rapidly adapted to a burst signal whose amplitude varies in a wide range. By using an adaptive level detection method, a multi-level digital AGC can be implemented without using ADC. In addition, because the transimpedance amplifier uses a selective reset generation scheme that performs a reset operation for itself after a high power burst, a burst mode operation can be performed without external reset signals. Accordingly, the transimpedance amplifier can be integrated with an optical detector within a TO-can. Furthermore, the transimpedance amplifier can have the burst mode capability and the best sensitivity. | 01-21-2010 |
20100135665 | BURST MODE OPTICAL REPEATER - A burst mode optical repeater is provided. The burst mode optical repeater receives optical signals, which are transmitted from a plurality of optical network units (ONUs) in a passive optical network (PON) to a central office using a time division multiplexing access (TDMA) method, and relays the received optical signals using an optical-electrical-optical (OEO) method. Since the burst mode optical repeater can be installed anywhere between an optical line terminal (OLT) and the ONUs, the number of subscribers and transmission range that can be supported by a corresponding network can be increased. | 06-03-2010 |
20100135666 | CLOCK PHASE ALIGNING APPARATUS FOR BURST-MODE DATA - Disclosed is a clock phase aligning apparatus capable of synchronizing a clock signal in the middle of an upstream burst mode data bit in an optical line terminal of a passive optical network. The clock phase aligning apparatus effectively aligns a phase of a clock signal with a phase of data during an overhead period of burst mode packet data through an over-sampling scheme and a digital scheme. Burst mode data signals are subject to an over-sampling through a high speed continuous mode analog circuit and then converted into low speed parallel signals through a parallel conversion unit. Such low speed parallel signals are processed with respect to sampling patterns through a digital look-up scheme in a logic circuit device such that the phase of data is arranged with the phase of a clock signal during a limited bit stream specified in a burst mode preamble timing. | 06-03-2010 |
20100266286 | Medium access control method for optical-fiber tdma networks - A medium access control method for optical-fiber TDMA networks is revealed. The TDMA indicates the technique of time-division multiple access which is used to provide medium-sharing environment. Once the MAC protocol implementing traffic control is applied to control access among nodes with the same optical fiber, the medium access in optical networks can be distributed logically and effectively among the nodes so as to improve unfair access in the optical TDMA networks. Therefore, the optical TDMA network is suitable to construct metropolitan area networks (MANs), local area networks (LANs) or subnetworks of public networks for reducing construction cost of networks, increasing bandwidth utilization and improving communicative performance. | 10-21-2010 |
20100296814 | METHOD AND DEVICE FOR OPTICAL DATA TRANSMISSION - The invention relates to a method and device for optical data transmission, in particular a method for transmission of data by means of digitised infrared signals. Data sequences are transmitted using a time-division multiplex access protocol with communication frames comprising single sequential windows with a given minimal bit transmission rate. At least one control impulse sequence is provided in each communication frame. According to the invention, the control impulse sequence is transmitted at a bit transmission rate which is lower than the minimum bit Transmission rate for the data sequence. | 11-25-2010 |
20120008959 | APPARATUS AND METHOD FOR SUPPORTING MOBILITY OF A MOBILE TERMINAL THAT PERFORMS VISIBLE LIGHT COMMUNICATION - A method and apparatus for supporting mobility of a mobile terminal in a Visible Light Communication (VLC) system. The method includes searching, by the VLC device, for a first mobile terminal in a plurality of cells; locating the first mobile terminal in a first cell among the plurality of cells; exchanging data with the first mobile using a light source of the first cell; determining whether a response signal corresponding to data reception is received from the first mobile terminal in the first cell; searching for the first mobile terminal in a neighboring cell of the first cell, if the response signal is not received; and determining the neighboring cell as a second cell for visible light activation, if the first mobile terminal is located in the neighboring cell. | 01-12-2012 |
20120237224 | OPTICAL DATA BUS AND METHOD - An optical data bus transceiver ( | 09-20-2012 |