Patents Issued in September 2, 2004
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Publication number: 20040170195Abstract: A CAN device that supports a plurality n (where n≧3) of message objects, including a plurality of registers associated with each message object, including at least one object match ID register that contains a multi-bit object match ID field, and at least one object mask register that contains a multi-bit object mask field; and, a CAN/CAL module that processes incoming messages. The CAN/CAL module assembles a multi-bit screener ID from selected bits of each incoming message to be acceptance filtered, compares the bits comprising the screener ID with corresponding bits of the object match ID field associated with each of at least designated ones of the plurality n of message objects, disregarding any bits of each object match ID field that are masked by corresponding bits of the associated object mask field, and then determines whether any of the comparisons results in a match.Type: ApplicationFiled: March 10, 2004Publication date: September 2, 2004Inventors: William J. Slivkoff, Neil Edward Birns, Hong Bin Hao, Richard Joun Fabbri
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Publication number: 20040170196Abstract: Commands are passed between first and second asynchronous clock domains. Unique coded command signals are inserted into a data stream transmitted from the first asynchronous clock domain to the second asynchronous clock domain. They are passed without change from the first asynchronous clock domain to the second asynchronous clock domain through an elastic buffer. The unique coded command signals are then decoded in receiver circuitry in the second asynchronous clock domain. Process circuitry in the second asynchronous clock domain is controlled according to the decoded command signals.Type: ApplicationFiled: March 4, 2004Publication date: September 2, 2004Applicant: Intel CorporationInventor: Dean S. Susnow
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Publication number: 20040170197Abstract: A method of synchronising an Orthogonal Frequency Division Multiplexed (OFDM) IEEE 802.11a data packet at a receiver is disclosed. The 802.11a data packet has a series of short training sequence (STS) symbols as a preamble. Cross-correlation at the receiver of the STS in the 802.11a packet PLCP preamble with the modified reference STS, that is circular shifted by eight samples, results in a main correlation peak but with reduced pre- and post-lobes.Type: ApplicationFiled: November 7, 2003Publication date: September 2, 2004Inventor: Mehul Mehta
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Publication number: 20040170198Abstract: A method, apparatus and software program is provided for scheduling and admission controlling of real-time data packet traffic. Data packets are admitted or rejected for real-time processing according to throughput capabilities of a packet scheduler. A delivery deadline is determined for each payload data packet at the packet scheduler and packets are sorted into a time-stamp-based queue. Deadline violations are monitored and an adaptation of payload data packets can be triggered on demand in order to enter a stable state.Type: ApplicationFiled: March 9, 2004Publication date: September 2, 2004Applicant: Telefonaktiebolaget LM Ericsson (publ)Inventors: Jens Meggers, Andreas Fasbender
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Publication number: 20040170199Abstract: The invention provides a system and method for compensating for timing violations of a multiplex of at least two streams of media packets. The method includes the steps of: receiving the multiplex; associating a transmitter timing information to media packets; whereas the multiple media packet streams are associated to different time bases; transmitting the media packets and the associated transmitter timing information over a timing violation inducing communication channel to a receiver; receiving, by the receiver, the transmitter timing information and the media packets; providing at least one timing violation compensated stream of media packets in response to the transmitter timing information.Type: ApplicationFiled: July 14, 2003Publication date: September 2, 2004Inventors: Oded Golan, Gilat Avieli, Eran Avieli, Shlomo Abuddi, David Kalma
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Publication number: 20040170200Abstract: A system and method for establishing a known timing relationship between two clock signals, wherein a first clock signal is operable to clock data transfer operations from a transmitter domain to a receiver domain and a second clock signal is operable to be transported to the receiver domain. Circuitry is provided for detecting an edge in a global framework clock (GFC) signal that is supplied to the transmitter domain. A common alignment signal is manufactured that is based at least in part upon the GFC signal. A multiplexer and register arrangement is operable to output the second clock signal in response to the common alignment signal which is also used for gating the data transfer operations clocked by the first clock signal.Type: ApplicationFiled: February 28, 2003Publication date: September 2, 2004Inventor: Rajakrishnan Radjassamy
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Publication number: 20040170201Abstract: A first demultiplexer (11) and a second demultiplexer (12) receive and demultiplex STM-64 data to generate parallel data. A FEC frame generating encoder (13) carries out error correction encoding operation in a column direction of the parallel data that constitutes a matrix, adds a resulting error correcting code to the parallel data, carries out error correction encoding operation in a row direction of the parallel data, and further adds a resulting error-correcting code to the parallel data. A first multiplexer (14) and a second multiplexer (15) multiplex the error-correction-encoded parallel data, and output the data as a FEC frame.Type: ApplicationFiled: December 5, 2003Publication date: September 2, 2004Inventors: Kazuo Kubo, Hideo Yoshida
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Publication number: 20040170202Abstract: By operating a mode switch, a user switches a laser light source module into one of five operation modes: a difficult detection/normal mode, a difficult detection/energy-saving mode, an easy detection/normal mode, an easy detection/energy-saving mode, and a photodetector mode. A ROM stores therein five combinations of data in one to one correspondence with the five operation modes. Each data combination includes data of drive frequency and data of ON duty ratio. When the user selects his/her desired mode, a CPU reads, from the ROM, one data combination of drive frequency and ON duty ratio that corresponds to the user's selected mode. The CPU applies the base of the transistor with a pulse drive voltage, whose repetition period and whose pulse width correspond to the read drive frequency and ON duty ratio. A laser diode oscillates in pulses with the drive frequency and ON duty ratio.Type: ApplicationFiled: February 26, 2004Publication date: September 2, 2004Inventor: Takashi Nishimura
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Publication number: 20040170203Abstract: A multi-beam semiconductor laser device capable of emitting respective laser beams with uniform optical output levels and enabling easy alignment is provided. This multi-beam semiconductor laser device (40) is a GaN base multi-beam semiconductor laser device provided with four laser stripes (42A, 42B, 42C and 42D) which are capable of emitting laser beams with the same wavelength. The respective laser oscillating regions (42A to 42D) are provided with a p-type common electrode (48) on a mesa structure (46) which is formed on a sapphire substrate (44), and have active regions (50A, 50B, 50C and 50D) respectively. Two n-type electrodes (52A and 52B) are provided on an n-type GaN contact layer (54) and located as common electrodes opposite to the p-type common electrode (48) on both sides of the mesa structure (46). The distance A between the laser stripe (42A) and the laser stripe (42D) is no larger than 100 &mgr;m.Type: ApplicationFiled: December 12, 2003Publication date: September 2, 2004Inventors: Tsuyoshi Tojo, Tomonori Hino, Osamu Goto, Yoshifumi Yabuki, Shinichi Ansai, Shiro Uchida, Masao Ikeda
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Publication number: 20040170204Abstract: An electro-optical system includes a plurality of electromagnetic gain media having a corresponding plurality of apertures. The apertures are disposed in a predetermined spatial distribution. The system further includes a refracting surface disposed to intercept energy from the plurality of apertures and a partially reflecting surface to direct portions of the intercepted energy back toward the plurality of apertures with the directed energy being distributed about the plurality of apertures.Type: ApplicationFiled: January 22, 2004Publication date: September 2, 2004Inventor: Christopher J. Corcoran
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Publication number: 20040170205Abstract: Laser equipment in which pumping intensity-dependent variation in output beam diameter and beam wavefront curvature is reduced. The total pumping energy of at least one of laser active media disposed endwise beyond terminal beam waists among a plurality of beam waists is made approximately half of the total pumping energy of laser active media disposed between two adjacent beam waists among the plurality of beam waists.Type: ApplicationFiled: April 15, 2004Publication date: September 2, 2004Inventors: Susumu Konno, Tetsuo Kojima, Shuichi Fujikawa
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Publication number: 20040170206Abstract: An optically pumped laser has a gain medium positioned inside of an optical resonator cavity and disposed about a resonator optical axis. An optical pumping source is positioned outside of the optical resonator cavity. A reflective coupler with a coupler body, and an interior volume passing therethrough is positioned proximal to the optical pumping source. Light from the pumping source passes into an entrance aperture of the reflective coupler to an exit aperture of the reflective coupler positioned distal to the optical pumping source. The interior volume of the reflective coupler is bounded by a reflective surface, an entrance aperture and the exit aperture, and is substantially transparent to radiation from the optical pumping source. The reflective surface has a high reflectivity matched to radiation from the optical pumping source.Type: ApplicationFiled: December 16, 2003Publication date: September 2, 2004Inventors: Jason D. Henrie, William L. Nighan
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Publication number: 20040170207Abstract: An optical beam splitter arrangement comprising two beam splitter mounts one of which is turnable relative to the other by flexing a deformable connection. By controlling the turn angle of rotation it is possible to use the light reflected by one of the beam splitters to monitor the output power of a laser and to use the light reflected by the other beam splitter to monitor the wavelength transmitted by the laser.Type: ApplicationFiled: February 4, 2004Publication date: September 2, 2004Inventors: Declan Reilly, Simon Meadowcroft
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Publication number: 20040170208Abstract: Known laser diode selections are limited to those designed for high power applications (high gain) or those designed for stable single mode operation in an external cavity (low gain). Exponential gain of laser diodes implemented according to embodiments of the present invention is improved (i.e., optimized) to provide both high output power and stability in an external cavity. This is accomplished by controlling the number of quantum wells, light confinement factor, and the transparency current of the laser diode.Type: ApplicationFiled: February 27, 2003Publication date: September 2, 2004Inventor: Sergei Sochava
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Publication number: 20040170209Abstract: The invention relates to the stabilization of high power semiconductor laser diode sources as they are extensively used in the field of optical communication. Such lasers are mostly employed as so-called pump laser sources for fiber amplifiers, e.g. erbium-doped fiber amplifiers, and are designed to provide a narrow-bandwidth optical radiation with a stable power output in a given frequency band. To improve the wavelength locking range of such laser sources when operating without an active temperature stabilizing element, an external reflector providing very high relative feedback is used. The reflectivity bandwidth of the external reflector is broadened for improving the stability of the laser source. In commonly employed optical fibers for conducting the laser beam, the external reflector is formed by one or a plurality of appropriately designed fiber Bragg gratings.Type: ApplicationFiled: February 10, 2004Publication date: September 2, 2004Inventors: Nicolai Matuschek, Stefan Mohrdiek, Tomas Pliska
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Publication number: 20040170210Abstract: Blocks of organic material (58) are fed from a plurality of directions into a reactor (10) having three zones (16, 18, 19). The material forms a bed (70) atop a bed of consumable carbon catalyst (60). These beds are heated by a series of plasma arc torches (42) mounted in inlets (37) about the reactor. Gas is supplied via inlets (39, 41) from wind drums (38, 40). The superheated gas from the reaction is vented through an outlet (30) and is used to produce electrical energy.Type: ApplicationFiled: December 29, 2003Publication date: September 2, 2004Inventors: Robert T. Do, Gary L. Leatherman
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Publication number: 20040170211Abstract: A thermal management utensil system for cooling food and beverages to a desirable temperature without diluting them. The thermal management utensil system includes an elongate handle member, a scoop member attached to the handle member, a reservoir within the scoop member and a volume of coolant within the reservoir. The handle member is preferably comprised of an insulating material.Type: ApplicationFiled: February 27, 2003Publication date: September 2, 2004Inventor: Erin E. Paul
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Publication number: 20040170212Abstract: A control structure and method for controlling a sensor heater including a power supply connected to a switching device for pulse width modulating a voltage from the power supply. The switching device is further connected to a resistance heater. A microcontroller having a single output is connected to the switching device and a single input from the microcontroller is connected to a high side of the resistance heater. The microcontroller determines a pulse width modulation duty cycle to maintain a constant power dissipation of the resistance heater.Type: ApplicationFiled: February 28, 2003Publication date: September 2, 2004Inventors: James W. Streit, Dale M. Harris
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Publication number: 20040170213Abstract: A food safety thermometer is provided that is easily calibratable. The thermometer includes a digital display for displaying the temperature of food items under measurement. A calibration unit is coupled to the digital display. The calibration unit generates a calibration alert when the measured temperature is maintained within a calibration range for a predetermined period of time (the calibration period). If the user elects to calibrate the thermometer during the calibration period, the may activate the calibration unit and the calibration unit drives the measured temperature to the calibration temperature.Type: ApplicationFiled: February 27, 2003Publication date: September 2, 2004Inventors: Richard Rund, Pierre Charlety
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Publication number: 20040170214Abstract: A food safety thermometer is provided that measures the temperature of a food item and notifies the user when the food item has maintained a preselected temperature for a predetermined amount of time.Type: ApplicationFiled: February 27, 2003Publication date: September 2, 2004Inventor: Richard Rund
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Publication number: 20040170215Abstract: An imager temperature sensor and a current correction apparatus are provided which use dark pixel measurements from an imager chip during operation together with a fabrication process constant as well as a chip dependent constant to calculate chip temperature. The chip temperature may be used to generate a current correction signal. The correction signal is used to tune a current on the imager chip to correct for temperature variations.Type: ApplicationFiled: March 12, 2004Publication date: September 2, 2004Inventors: Giuseppe Rossi, Gennadiy A. Agranov
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Publication number: 20040170216Abstract: An axillary thermometer for measuring the temperature of a patient comprising a first disk-shaped member having a circumferential edge, and an upper portion and lower portion, that is integrally connected, and angularly situated, via a connecting member joint, to a second disk-shaped member having a top side and a bottom side. The top side of the second disk-shaped member, including an actuation switch and display, being proximate the upper portion of the first disk-shaped member such that viewing of the temperature display can be simultaneously accomplished with the temperature taking process. The first disk-shaped member further having at least one temperature sensor along its circumferential edge of the upper portion with the at least one temperature sensor being connected to at least one temperature sensing circuitry.Type: ApplicationFiled: November 25, 2003Publication date: September 2, 2004Inventors: Stephen Russak, Andrew Howansky, Jim Best, Scott Henderson, Timothy Kennedy, Daniel Formosa, Wilfrido L. Canizares
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Publication number: 20040170217Abstract: Wireless personal area networks with frequency hopping and rotation of the frequency hopping sequences. In one embodiment, a method of wireless communication is provided, the method including: transmitting a beacon frame by a piconet coordinator that specifies a rotation index and hopping index; receiving a beacon frame by a device associated with or to be associated with the piconet coordinator; extracting the rotation index and hopping index by the MAC of the recipient device and communicating them to the PHY for transmission and reception in a current superframe; missing a subsequent beacon frame by a recipient device; and using the rotation index and hopping index previously received to determine a current frequency hopping sequence for a current superframe following the missed beacon frame.Type: ApplicationFiled: December 12, 2003Publication date: September 2, 2004Applicant: Texas Instruments IncorporatedInventor: Jin-Meng Ho
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Publication number: 20040170218Abstract: A rake receiver detects a transmitted ultra wide bandwidth radio signal. The receiver includes a front end for converting a received version of the transmitted radio signal into an electrical signal. Multiple rake fingers process the electrical signal in parallel. Each rake finger includes the following components that can be connected serially in an arbitrary order. A programmable pulse generator generates a sequence of pulses. A multiplier connected to an output of the front end and to an output of a programmable pulse generator generates a signal functionally related to a product of the output of the front end and the output of the programmable pulse generator. A low-pass filter to filter an output of the multiplier, and an adjustable weight block scale an output of the low-pass filter.Type: ApplicationFiled: March 1, 2003Publication date: September 2, 2004Inventors: Andreas Molisch, Giovanni Vannucci, Jinyun Zhang
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Publication number: 20040170219Abstract: The present invention provides a diversity receiver and diversity reception method utilized for CDMA communication system. Antenna switching using antenna diversity is made possible with one decoding subsystem without losing the received data. A receive subsystem 6 receives an intermittent signal for standby operation by a first antenna 1 or a second antenna 2, the signal being sent out every slot cycle from each base station. Information about the received field strengths at the first and second antennas, 1 and 2, is acquired from the signal received by the receive subsystem 6. Base on this information, one of the first antenna 1 and second antenna 2 in a better reception environment when a transition is made from standby mode to a phone conversation is switched and connected to the receive subsystem 6. Then, the conversation is performed.Type: ApplicationFiled: January 15, 2004Publication date: September 2, 2004Applicant: Matsushita Electric Industrial Co., Ltd.Inventors: Makoto Sasaki, Wataru Tomiya, Ken Muramatsu
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Publication number: 20040170220Abstract: A rake architecture for a frequency division duplex (FDD) and use also in TDD and TD-SCDMA type communications system, designed to significantly reduce the memory capacity required and thereby also reduce an area on the die of an application specific integrated circuit (ASIC) into which the memory is integrated. A single circular buffer, preferably of the shared memory type is shared by all of the rake fingers of a rake receiver to significantly reduce the hardware and software required to time align multipath signals received by a UE from a base station. This unique time alignment technique also reduces the number of code generators required to track a plurality (typically three) of base stations.Type: ApplicationFiled: March 4, 2004Publication date: September 2, 2004Applicant: InterDigital Technology CorporationInventor: William C. Hackett
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Publication number: 20040170221Abstract: A mobile wireless communications device and methods therefore, including receiving a signal (710), storing a portion of the received signal (730), identifying all possible pilot signals by determining slot boundary information for the stored signal portion (720), determining frame boundary information and/or scrambling code information (760) of the stored signal portion by correlating the stored signal portion with the scrambling codes based on the slot boundary information. In other embodiments, the search is performed in real-time without storing the signal.Type: ApplicationFiled: February 27, 2003Publication date: September 2, 2004Inventors: Brian Storm, Qiang Guo, Ming D. Tan, Xuping Zhou, Mang Zhu
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Publication number: 20040170222Abstract: Apparatus and methods for determining an operational mode of a far-end modem are disclosed. Where the multimode modem is a call initiator, a method according to the invention includes transmitting a V.8 ANSam tone to the far-end modem, receiving a response signal from the far-end modem, and determining from the response signal whether the far-end modem is a commercial modem or a secure modem. Where the multimode modem is a call responder, a method according to the invention includes transmitting to the far-end modem a P1800 Hz tone with phase reversals, receiving a response signal from the far-end modem, and determining from the response signal whether the far-end modem is a commercial modem or a secure modem.Type: ApplicationFiled: March 11, 2004Publication date: September 2, 2004Applicant: L-3 Communications CorporationInventor: Frank A. Costantini
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Publication number: 20040170223Abstract: A series of digit processing units (DPUs) are connected to form a finite impulse response (FIR) filter. Each DPU includes a register, a multiplexer, and a coefficient multiplier. The register stores and delays an input digital signal to be filtered. The multiplexer has inputs connected to the input node and to an output of the register, an output of the multiplexer for connecting to a next stage DPU. The coefficient multiplier is connected to the output of the register and multiplies the input signal by a coefficient or part of a coefficient. A group of DPUs can have multiplexers set so that the register of each DPU stores the same part of the input signal for processing a single filter coefficient. An adder is provided to sum output of the DPUs and output a filtered signal. The critical path of the FIR filter is independent of coefficient number and precision.Type: ApplicationFiled: March 2, 2003Publication date: September 2, 2004Inventors: Tzi-Dar Chiueh, Kuan-Hung Chen
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Publication number: 20040170224Abstract: A communication system for transmitting a transmission signal in digital form from a transmitter to a receiver is disclosed. The transmitter includes a modulation part modulating a carrier wave in accordance with the transmission signal according to frequency modulation, a digital conversion part performing 1-bit quantization on the modulated signal obtained as a result of the modulation in the modulation part, and a transmission part transmitting digital data into which the modulated signal is converted in the digital conversion part. The receiver includes a reception part receiving the digital data transmitted from the transmission part, and a demodulation part demodulating the digital data received by the reception part according to the frequency modulation.Type: ApplicationFiled: February 13, 2004Publication date: September 2, 2004Inventor: Toshikazu Ogino
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Publication number: 20040170225Abstract: In a transmission system with Tomlinson preceding, the data are transmitted with N amplitude levels. In order to be able to resume the data transmission quickly and with little outlay after a temporary interruption, test signals (15-18) with data symbols which have W amplitude levels out of the overall N amplitude levels are transmitted in a warm-start phase for synchronisation or adjustment of a receiver (C), W and N being integers and W being <N. Even though only W amplitude levels are transmitted, the test signals are Tomlinson-precoded using N levels on the transmitter side and decoded using N levels on the receiver side, so that the transient process of the Tomlinson filter (2) is not perturbed when switching over to the N-level data mode and it is not necessary to change the Tomlinson preceding and decoding which depend on the number of data levels. The invention can be used, in particular, for the SDSL standard, although it may be used in all systems with Tomlinson preceding.Type: ApplicationFiled: December 29, 2003Publication date: September 2, 2004Inventors: Stefan Krause, Heinrich Schenk
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Publication number: 20040170226Abstract: Multi-carrier modulation fiber optic systems constructed using a series of electrical carriers, modulating the data on the electrical carriers and combining the carriers to form a wideband signal. The wideband signal can then be intensity modulated on a laser and coupled to a fiber optic channel. A receiver may then receive the laser signal from the fiber optic channel and convert it into an electrical signal. Multi-carrier modulation may be applied to existing fiber channels, which may be of lower quality. Existing fiber channels may have characteristics which prevent or restrict the transmission of data using intensity modulation at certain frequencies. An adaptive multi-carrier modulation transmitter may characterize an existing fiber optic channel and ascertain the overall characteristics of the channel. The transmitter and receiver can then be configured to use various bandwidths and various modulations in order to match the transfer characteristic of the fiber channel.Type: ApplicationFiled: November 14, 2003Publication date: September 2, 2004Inventor: Oscar E. Agazzi
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Publication number: 20040170227Abstract: In order to correct frequency deviations of signals in a multicarrier system, such as a OFDM-system, the present invention provides a frequency tracker and a method to operate the same. The frequency tracker is based on a decision directed digital phase locked loop exhibiting a predictive character. On the basis of an estimated phase offset for a received signal (signal component, signal symbol) a predicted phase offset is calculated and applied to the signal (signal component, signal symbol). Further, received signals (signal components, signal symbols) are sampled and for each sample a sample phase offset to be corrected is calculated in dependence to the related estimated phase offset to incorporate the predictive character.Type: ApplicationFiled: January 5, 2004Publication date: September 2, 2004Applicant: Telefonaktiebolaget LM EricssonInventors: Georg Frank, Mathias Pauli, Udo Wachsmann, Peter Schramm
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Publication number: 20040170228Abstract: The system includes a transmitter for generating a signal in the time domain and transforming the signal to the frequency domain, wherein the transmitter suppresses a plurality of sub-carriers of the signal, The resulting truncated signal is transmitted to the receiver through a noisy channel. The receiver receives a noisy signal and recovers the carrier signal and, hence, the partial response signal from the noisy signal. The method includes selecting a cyclic convolver having predefined values, applying the cyclic convolver to a signal to produce a partial response signal, dropping a plurality of sub-carriers of the partial response signal, to generate a modulated carrier signal that is ready for transmission.Type: ApplicationFiled: March 3, 2004Publication date: September 2, 2004Applicant: Nokia CorporationInventor: Venkatesh Vadde
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Publication number: 20040170229Abstract: The present invention is a method and system for receiving data transmitted using block space time transmit diversity (BSTTD) in a code division multiple access (CDMA) communication system. The system comprises a transmitter, for transmitting a first data field using a first antenna and a second data field using a second antenna, and a receiver. The receiver includes an antenna for receiving the first and second transmitted data fields, and a BSTTD joint detector which determines symbols of the first and second transmitted data fields using a minimum mean square error block linear equalizer model and an approximated Cholesky decomposition of the model.Type: ApplicationFiled: March 3, 2004Publication date: September 2, 2004Applicant: InterDigital Technology CorporationInventor: Younglok Kim
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Publication number: 20040170230Abstract: A method and apparatus for noise cancellation in a multi-channel communication system is disclosed. In one embodiment this system is configured to cancel FEXT on a victim channel utilizing the signals received on the other channels. The processing benefits gained by a receiver's other filters, such as for example, the FFE and DFE filters, is utilized when generating a FEXT cancellation signal. As a result, the complexity of the apparatus that generates the FEXT cancellation signal may be made less complex since part of the processing burden is performed by other filter apparatus. In one configuration pre-code FEXT cancellation occurs in that a pre-code FEXT filter generates one or more pre-code FEXT cancellation signals corresponding to each of the other channels. The pre-code FEXT cancellation signals are combined, prior to transmission, with the signals associated with each of the other channels, to thereby pre-cancel FEXT prior to transmission.Type: ApplicationFiled: June 24, 2003Publication date: September 2, 2004Inventors: George A. Zimmerman, William W. Jones
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Publication number: 20040170231Abstract: A technique for determining an optimal transition-limiting code for use in a multi-level signaling system is disclosed. In one particular exemplary embodiment, the technique may be realized as a method for determining an optimal transition-limiting code for use in a multi-level signaling system. Such a method comprises determining a coding gain for each of a plurality of transition-limiting codes, and selecting one of the plurality of transition-limiting codes having a largest coding gain for use in the multi-level signaling system.Type: ApplicationFiled: September 23, 2003Publication date: September 2, 2004Inventors: Anthony Bessios, Jared Zerbe
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Publication number: 20040170232Abstract: A P-BRO interleaver and a method for optimizing parameters according to an interleaver size for the P-BRO interleaver. The P-BRO interleaver sequentially, by columns, arranges an input data stream of size N in a matrix having 2m rows and (J−1) columns, and R rows in a Jth column, P-BRO interleaves the arranged data, and reads the interleaved data by rows.Type: ApplicationFiled: December 2, 2003Publication date: September 2, 2004Inventors: Sang-Hyuck Ha, Min-Goo Kim
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Publication number: 20040170233Abstract: A normalization for soft symbol estimates as reciprocal of the squared channel norm corresponding to each symbol.Type: ApplicationFiled: February 27, 2003Publication date: September 2, 2004Inventors: Eko N. Onggosanusi, Srinath Hosur, Anand G. Dabak
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Publication number: 20040170234Abstract: A method of operation of a receiver of a mobile station or a base station of a radio access network and corresponding equipment, the method for especial use in providing interference cancellation according to a single antenna interference cancellation (SAIC) algorithm. The method includes a step (22) in which a channel estimator (12) estimates channel impulse response components for use by a SAIC equalizer (14); in estimating the channel impulse response components, the channel estimator (12) minimizes a special cost function (Jch(h)) with respect to the components of the channel impulse response h. In some embodiments, the method uses an iterative least mean squares procedure to minimize the cost function (Jch(h)).Type: ApplicationFiled: May 15, 2003Publication date: September 2, 2004Inventors: Markku Pukkila, Gian Paola Mattellini, Pekka A. Ranta
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Publication number: 20040170235Abstract: This invention provides an iterative process to maximum a posteriori (MAP) decoding. The iterative process uses an auxiliary function which is defined in terms of a complete data probability distribution. The auxiliary function is derived based on an expectation maximization (EM) algorithm. For a special case of trellis coded modulators, the auxiliary function may be iteratively evaluated by a combination of forward-backward and Viterbi algorithms. The iterative process converges monotonically and thus improves the performance of any decoding algorithm. The MAP decoding minimizes a probability of error. A direct approach to achieve this minimization results in complexity which grows exponentially with T, where T is the size of the input. The iterative process avoids this complexity by converging on the MAP solution through repeated maximization of the auxiliary function.Type: ApplicationFiled: February 28, 2004Publication date: September 2, 2004Inventor: William Turin
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Publication number: 20040170236Abstract: Coding section 205 recodes decoded data stored in decoded data storage section 204, data conversion section 206 converts data “0” and “1” output from coding section 205 to “1” and “−1” respectively, sum-of-product calculation section 207 multiplies the data output from data conversion section 206 by the demodulated data (soft decision value) stored in demodulated data storage section 201 and then calculates the sum of the products for 1 TTI and stores the sum-of-product result for each data rate, data rate decision section 208 decides the data rate corresponding to a maximum value of the sum-of-product results as the data rate of the demodulated data. This makes it possible to improve the accuracy of data rate decision and reduce decoding errors of a received signal.Type: ApplicationFiled: March 8, 2004Publication date: September 2, 2004Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.Inventors: Kuniyuki Kajita, Takashi Toda, Hidetoshi Suzuki, Masatoshi Watanabe
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Publication number: 20040170237Abstract: Using a combination of auto-correlation and cross-correlation techniques provides a symbol timing recovery in a Wireless Local Area Network (WLAN) environment that is extremely robust to wireless channel impairments such as noise, multi-path and carrier frequency offset. An auto-correlator provides an estimate for a symbol boundary, and a cross-correlator is subsequently used to more precisely identify the symbol boundary. Peak processing of the cross-correlation results provides further refinement in symbol boundary detection. In receiving a packet conforming to the IEEE 802.11a standard, the method requires a minimum of only three short symbols of the 802.11a short preamble to determine timing, and guarantees timing lock within the duration of the 802.11a short preamble. This method and system can be easily applied to any other preamble based system such as 802.11g and High Performance Radio LAN/2 (HIPERLAN/2).Type: ApplicationFiled: November 13, 2003Publication date: September 2, 2004Applicant: Engim, Inc.Inventors: Kanu Chadha, Maneesh Soni, Manish Bhardwaj
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Publication number: 20040170238Abstract: A frequency synchronizing apparatus synchronizes the oscillation frequency of a receiving device to the oscillation frequency of a transmitting device. The frequency synchronizing apparatus receives, from the transmitting device, frames in which symbols having identical time profiles have been embedded, calculates a correlation value between the identical time profile portions in neighboring frames of a receive signal, obtains the phase of the correlation value (a complex number) as a frequency deviation between the transmitting device and the receiving device, and controls oscillation frequency based upon the phase.Type: ApplicationFiled: February 26, 2004Publication date: September 2, 2004Inventors: Koji Matsuyama, Makoto Yoshida, Tetsuya Yano
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Publication number: 20040170239Abstract: The invention relates to a method for the operation of a message receiver for a message, that is present as burst, which includes at least a training sequence and useful data, characterized in that the receiver is stepwise synchronized with the burst as the burst is received.Type: ApplicationFiled: September 5, 2003Publication date: September 2, 2004Inventors: Khaled Fazel, Volker Hespelt, Volker Engels, Bernd Freidrichs
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Publication number: 20040170240Abstract: A register-based de-skew system and method for a source synchronous receiver circuit domain. In one embodiment, a de-skew strobe generator operates responsive to at least one incoming strobe signal in order to generate a plurality of one-hot de-skew strobe signals. A plurality of de-skew registers receive the same input data pulses from a transmitter circuit domain. By clocking the de-skew registers with the one-hot de-skew strobe signals, the input data pulses are stretched into spread data pulses having an extended timing window. A plurality of multiplexers multiplex the spread data pulses, whereupon the multiplexed data is registered using a clock signal associated with the receiver circuit domain.Type: ApplicationFiled: February 28, 2003Publication date: September 2, 2004Inventor: Rajakrishnan Radjassamy
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Publication number: 20040170241Abstract: Two or more synchronous words are arranged to a section as long as a noise cycle “t” regarding a frame. Or, one or more synchronous words are arranged such that a section not being influenced by the noises is long enough considering the noise cycle. When information that cyclical noises occur is given and/or the noise cycle can be measured, probability that the synchronous word is influenced by the noises is reduced so that reliability of frame synchronization establishment can be improved.Type: ApplicationFiled: February 19, 2004Publication date: September 2, 2004Inventors: Junji Kondou, Yuji Igata, Akio Kurobe, Shigeo Yoshida, Norihiro Miyashita
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Publication number: 20040170242Abstract: The present invention relates to a method for transmitting packets comprising a synchronization part (sync′) and a payload part (dat1, dat2), wherein the transmission format comprises a shortened synchronization part (syn′) and the payload part is split into a first data sequence (dat1), encoded in the first encoding, followed by the second data sequence (dat2), encoded in the second encoding, comprising the steps of encoding and sending the first data sequence (dat1) in the first encoding, encoding and sending the second data sequence (dat2) in the second encoding, on the sender side and receiving and decoding the first data sequence (dat1) in the first encoding, detecting the end of the first data sequence and adapting the receiver's decoder, receiving and decoding the second data sequence (dat2) in the second encoding on the receiver side. The invention further relates to a sender, a receiver, an optical network element, and a serialized packet format.Type: ApplicationFiled: February 9, 2004Publication date: September 2, 2004Applicant: ALCATELInventor: Wolfram Lautenschlager
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Publication number: 20040170243Abstract: In the field of optical communications, the need to remove jitter from a Synchronous Digital Hierarchy (SDH) or Synchronous Optical NETwork (SONET) datastream is recognized. Consequently, the present invention provides a First-In-First-Out (FIFO) buffer having a read-out clock frequency that is controlled in response to a depth error of the FIFO buffer. The control of the read-out clock frequency is achieved by a hardware control loop coupled to the FIFO buffer. The period of the control loop is a product of the frequency at which the depth error of the FIFO buffer is acquired and another factor. The another factor is the number of states of logic employed by the control loop raised to an integer power.Type: ApplicationFiled: February 27, 2003Publication date: September 2, 2004Inventor: Gordon Old
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Publication number: 20040170244Abstract: The receiver for clock and data recovery according to the invention comprises n sampling latches (SL1 . . . SLn) for determining n sample values (SV1 . . . SVn) of a reference signal (Ref2) at n sampling phases (&phgr;1a . . . (&phgr;na) having sampling latch inputs and sampling latch outputs. The receiver further comprises a phase position analyzer (5) connected to said sampling latch outputs for generating an adjusting signal (AS) for adjusting the sampling phase (&phgr;1a . . . (&phgr;na), if the sample value (SV1 . . . SVn) deviates from a set point and a phase interpolator (9) for generating sampling phases (&phgr;1u . . . (&phgr;nu). A sampling phase adjusting unit (6) connected with its inputs to the phase position analyzer (5) and the phase interpolator (9) and with its outputs to the sampling latches (SL1 . . . SLn) is provided for generating adjusted sampling phases (&phgr;1a . . . (&phgr;na) depending on said sampling phases (&phgr;1u . . . (&phgr;nu) and said adjusting signal (AS).Type: ApplicationFiled: February 27, 2003Publication date: September 2, 2004Applicant: International Business Machines CorporationInventors: Hayden C. Cranford, Vernon R. Norman, Martin Schmatz