Abstract: A blind convergence process for an adaptive decision feedback equalizer that includes an quadrature amplitude modulation (QAM) slicer having a index n, a forward filter defined by a plurality of forward tap coefficients and a feedback filter defined by a plurality of feedback tap coefficients. The blind convergence process includes initializing the forward tap coefficients of the forward filter and the feedback tap coefficients of the feedback filters with predetermined values. The slicer operates in two modes: a clustering mode and a decision directed mode. In the clustering mode the following steps are performed: (1) update the forward tap coefficients of the forward filter using an error estimate (e.g. Sato error), and (2) update the feedback tap coefficients of the feedback filter using an error estimate (e.g. Sato error).
Type:
Grant
Filed:
April 29, 1998
Date of Patent:
November 20, 2001
Assignee:
Northern Telecom Limited
Inventors:
Edgar Velez, Ian Dublin, Richard Buz, Sisay Yirga
Abstract: The present invention relates to structures of the spread CDMA system of band diffusion with antenna array. The present invention, structures of 2-D demodulator are provided, for spread spectrum CDMA systems with antenna array which can increase coverage area of base station and system capacity, by extracting and combining all information needed in time and space domains, using only the information which shall be calculated in a CDMA system inherently.
Type:
Grant
Filed:
August 31, 1998
Date of Patent:
November 20, 2001
Assignees:
Electronics and Telecommunications Research Institute, SK Telecom Co., Ltd.
Inventors:
Kyung Hi Chang, Eung Soon Shin, Youn Ok Park, Mun Geon Kyeong
Abstract: A conventional antenna 114 at a cell site of a sectored cell in a cellular radio communications system has a low angle of coverage in elevation and therefore has low gain for close-in subscriber units (near the cell site). In a sectored cell, a main beam antenna in a first sector generates sidelobes and backlobes which may fall within the close-in area in other sectors. A close-in mobile in one of the other sectors may move into such an out-of-sector lobe and cause unexpected interference to the base station transceiver (BTS) of the first sector. A downward-looking antenna (DIA) 110 supplements the conventional antenna in each sector and has a beam 112 covering the close-in area. The gain of the DLA beam is greater than that of any out-of-sector lobes and so provides a subscriber unit with a higher gain link to the BTS of its own sector than is provided by out-of-sector lobes to the BTS of any other sector.
Type:
Grant
Filed:
November 24, 1998
Date of Patent:
October 30, 2001
Assignee:
Northern Telecom Limited
Inventors:
David Damian Nicholas Bevan, Steven John Baines
Abstract: The present invention provides for a system to achieve a high data rate channel in a CDMA system. According to the preferred embodiment, multiple CDMA data sequences are modulated in parallel by multiple low data rate CDMA channels. Each low data rate CDMA channel digitally delays the CDMA data sequence modulated thereby by a different period of time, where the largest period of time of all the digital delays is less than one-half the period of a single chip of data. The high data rate CDMA channel is created by combining the output of multiple low data rate CDMA channels operating in parallel, thereby resulting in significantly increased data throughput.
Abstract: The card reader has a body (12) defining a support area (30) for a card equipped with contact terminals (32). The body (12) has, on one side of the support area (30), tabs (34), for holding the card, extending partly facing the support area (30). The reader also has a lock, for retaining the card, which comprises a moving latch (52) for retaining the card. This latch (52) can move between a retaining position for said card and a release position for said card. The latch (52) is an integral part of said body (12).
Abstract: A method and an equipment for allocating to a television program, which is already conditionally accessed, a complementary conditional access. The television program is first received by means provided with access entitlements and the control words are restored. Complementary access control messages and complementary entitlement management messages corresponding to a complementary access control system are built up. The initial unmodified television program is rebroadcast, together with the complementary messages related to the complementary access control system.
Type:
Grant
Filed:
February 19, 1999
Date of Patent:
October 23, 2001
Assignees:
France Telecom, Telediffusion de France
Abstract: A telecommunication system for enabling a subscriber to calling features available by a central office to have access to such calling features when such subscriber is accessing the central office through either a line connected to the central office or an Internet, Intranet, Extranet (i.e., IP) network which uses the TCP/IP network protocol. The method includes the steps of: processing signals received by the central office from the subscriber through either the IP network or the line connected to the central office to determine whether the subscriber is placing a call to the central office through either the line to the central or through the IP network; and making such calling features available to the subscriber independent of whether the subscriber is connected to the central office through the line to the central office or through the IP network.
Abstract: In order to depict a set of paths which are available for transporting a stream from a first node (1) to a second node (6) of the network, one or more perimeters are placed around each symbol designating a departure node of an elementary link of a path of the set, and a respective flag is placed at the intersection between each arc designating an elementary link of the set of paths and a perimeter surrounding the symbol designating the departure node of said elementary link. This depiction technique permits clear visualization of various routing conditions, in a manner which is independent of the positions of the nodes in the graphical representation of the network. It is particularly well suited to computer tools for assisting the design or simulation of networks.
Abstract: A method of setting up two-way optical communication between a central unit and a remote unit suitable for operating in a given communication mode selected from a plurality of communication modes. A plurality of frame patterns is defined in the central unit, with each frame pattern being appropriate to one of the communication modes. The plurality of frame patterns are sent sequentially until a coherent response is obtained from the remote unit, the communication mode of the remote unit being the mode which corresponds to the frame pattern which gave rise to the coherent response.
Abstract: The invention concerns a connecting device which is intended to replace a keypad of a hand-held electronic device, such as e.g. a mobile telephone or a remote control device. A connecting disc (1) forming part of the device is tiltable about its center in different directions from a neutral position in order to bring electrical contact means (6, 10, 11) together for the purpose of generating electrical information signals. On one of its sides the connecting disc (1) is provided with alternating crests (4) and dales (5) departing radially from the center of the disc (1). A contact field (6) is provided on each crest (4). A printed circuit card (7) cooperating with the connecting disc (1) is formed with alternating crests (8) and dales (9). Each dale (9) is in this case provided with at least one pair of contacts (10, 11).
Abstract: A circuit and method that optimizes and adapts the bit and energy configurations of data sub-channels in a multi-channel data transmission signal is disclosed. A high speed system can select either of a first or a second adaptation routine to handle changes in the bit and gain loadings of sub-channel carriers based on line disturbances or transmission change requests, based on which is most aptly suited to handle the particular change. In a preferred embodiment the resulting bit/energy loadings can be adjusted to be fully compliant with applicable Discrete Multi-Tone (DMT) implementations of Asymmetric Digital Subscriber Loop (ADSL) protocols.
Type:
Grant
Filed:
February 22, 2000
Date of Patent:
September 18, 2001
Assignee:
Integrated Telecom Express, Inc.
Inventors:
Chiihsin Kao, Chunta Chen, Ming-Kang Liu
Abstract: A charge pump (2) is supplied to reset in rated conditions the error signal of a phase-locked loop of the type whereby a phase detector (1) periodically supplies this pump (2) with a first and second impulse having emission instants dependent on the phase ratio between phase-locked loop input signals and are allocated to control circuit output increase or decrease respectively by means of ring filter (3a, 3b). The pump features loops (21, 22, 23, 24, 28) to transform the first and second impulse into a first and second voltage signal of longer duration than maximum impulse duration and featuring values the difference of which depends on the phase ratio between the loop input signals and to generate a signal in a current representative of such difference.
Abstract: The subject of this invention is a method for matching transport channels included within a composite channel. Each transport channel transmits at least one data symbol (s). According to the invention, each symbol (s) to be transmitted is amplified by a gain (Gi) specific to the transport channel (i) from which said symbol (s) originates, in order to balance the Eb/I ratios between the different transport channels on the composite channel.
Type:
Application
Filed:
February 27, 2001
Publication date:
September 13, 2001
Applicant:
MITSUBISHI ELECTRIC TELECOM EUROPE (S.A.)
Abstract: The present invention relates to an optical component of the waveguide array spectrograph type, the component comprising an inlet coupler and an outlet coupler between which said array extends, and including optical channels constituting inlets and outlets for the inlet and outlet couplers, the component being suitable for multiplexing and/or demultiplexing two optical signals of different wavelengths conveyed by two channels of the same coupler, wherein the waveguides of the array have lengths that are distributed in such a manner that two spectrum ranges of different center wavelengths both occur in said same coupler, said different wavelengths that are conveyed by the two channels each belonging to a different one of the free spectrum ranges.
Abstract: The method is for forming porous silicon in a silicon substrate, in particular for improving the quality factor of an inductive circuit produced on a silicon semiconductor wafer which also incorporates integrated transistors. The rear face of the wafer, already incorporating the transistors and the inductive circuit on its front face, is placed in contact with an acid electrolyte containing hydrofluoric acid and at least one other acid. An anodic oxidation of the silicon of the wafer at the rear face is carried out so as to convert this silicon into porous silicon over a predetermined height from the rear face which is in contact with the electrolyte.
Type:
Grant
Filed:
May 4, 1999
Date of Patent:
September 11, 2001
Assignees:
STMicroelectronics S.A., France Telecom