By Signal Quality (e.g., Noise) Patents (Class 455/277.2)
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Patent number: 6690926Abstract: A multiple data stream processing arrangement includes a receiver/signal processor (14) and a plurality of signal input paths (11, 12) which meet at a junction (36). A junction output from the junction (36) provides a single input to the receiver/signal processor (14). A switching arrangement (16) is associated with the plurality of signal input paths (11, 12). The switching arrangement (16) includes a switch (31, 32) connected in each signal input path (11, 12). Each switch (31, 32) responds to an enable signal to allow a data stream applied to the respective input path (11, 12) to pass on to the junction (36) and to the receiver/signal processor (14). Only one signal input path (11, 12) and respective switch (31, 32) is enabled at any given time.Type: GrantFiled: March 6, 2001Date of Patent: February 10, 2004Assignee: Northpoint Technology, Ltd.Inventors: Carmen Tawil, Saleem Tawil
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Patent number: 6683906Abstract: A radio communication apparatus subjects each signal which is received via a multi-path and demodulated, to a Hadamard transform at each of fingers, by use of an M-ary quadrature coding scheme, obtains correlation values of codes, combines correlation values output from fingers which obtain valid correlation values, and demodulates a received signal based on a maximum correlation value of combined correlation values. The radio communication apparatus includes an operation unit which obtains a difference between a maximum value and a second largest value of the correlation values of a corresponding one of the fingers, and a lock controller which enables and locks the correlation values output from the corresponding one of the fingers when the difference obtained by the operation unit is greater than or equal to a predetermined value.Type: GrantFiled: March 1, 2000Date of Patent: January 27, 2004Assignee: Fujitsu LimitedInventor: Takanori Iwamatsu
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Patent number: 6684086Abstract: Direction of arrival estimation sections 106a and 106b estimate directions of arrival for communication terminals. Grouping decision section 107 divides the communication terminals that belong to a sector into a plurality of groups based on the results of direction of arrival estimations. Scramble code assignment control section 114 performs assignment control in such a way that a same scramble code is assigned to channels with similar (not necessarily completely the same) directivities.Type: GrantFiled: August 7, 2001Date of Patent: January 27, 2004Assignee: Matsushita Electric Industrial Co., Ltd.Inventor: Kazuyuki Miya
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Publication number: 20030228857Abstract: Events determine the timing of when to change performance, for example when to scan or when to use a prior stored usually best-performance configuration or just a last configuration, for a smart antenna in a fixed or almost fixed usage like a wireless local area network and a television system. Thereby the system maintains unchanged the parameters, such as those that determine the beam form of the smart antenna until monitoring recognizes one or a combination of more than one of the following conditions or event occurrences; the device communicate with another device for the first time; reboot of the device or the device turns on; the received signal exceeds a predetermined bit error rate (BER); the received signal strength indicator (RSSI) is less than a determined RSSI; the received signal goes below a predetermined signal to noise ratio (SNR); and a user's demand.Type: ApplicationFiled: June 6, 2002Publication date: December 11, 2003Applicant: Hitachi, Ltd.Inventor: Akira Maeki
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Patent number: 6654618Abstract: A variation compensating unit that compensates an amplitude variation and phase variation efficiently and that improves system reliability and communication quality. A first combining section generates a first combined signal by combining signal on different transmission paths in which a variation has not occurred. A second combining section generates a second combined signal by combining signal on the different transmission paths in which a variation has occurred. A compensation value calculating section calculates compensation values for compensating variation according to the transmission paths on the basis of the first combined signal, the second combined signal, and signal on each transmission path in which a variation has not occurred or in which a variation has occurred. A compensating section compensates variation dynamically on the basis of the compensation values.Type: GrantFiled: March 1, 2002Date of Patent: November 25, 2003Assignee: Fujitsu LimitedInventor: Shuji Kobayakawa
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Patent number: 6643526Abstract: A method of directional radio communication between a first station (6) and a second station, comprising the steps of defining at the first station (6) a plurality of beam directions (b1-b8) for transmitting signals to said second station, each of said beam directions being selectable. A plurality of beam directions are selected at said first station in which a signal is to be transmitted form said first station to said second station. Said signal i transmitted in said plurality of beam directions, whereby the power level of the signal transmitted in each of said selected plurality of beam directions is individually selectable.Type: GrantFiled: September 17, 1999Date of Patent: November 4, 2003Assignee: Nokia Telecommunications OyInventor: Marcos Katz
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Diversity system for receiving digital terrestrial and/or satellite radio signals for motor vehicles
Patent number: 6633258Abstract: The invention relates to a diversity reception system for motor vehicles for digitally modulated terrestrial and/or satellite radio signals in the frequency range above 1 GHz. The system includes an antenna arrangement of which the reception signal is supplied to a radio receiver. The antenna arrangement is designed as an antenna system having several individual antennas and several antenna components, and contains a controllable logic switching device. The individual antennas and the several antenna components are positioned on the vehicle so that for discrete switching positions of the controllable logic switch, reception signals that are different in terms of diversity are available at the antenna connection point. A reception level testing device is provided for the comparative determination of the reception level contained in the data flow in the HF-channel with an HF channel bandwidth B.Type: GrantFiled: March 1, 2002Date of Patent: October 14, 2003Assignee: FUBA Automotive GmbH & Co KGInventors: Heinz Lindenmeier, Jochen Hopf, Leopold Reiter, Michael Daginnus, Rainer Kronberger -
Publication number: 20030190904Abstract: The invention presents a fuzzy basis function network (FBFN) processing device for the beam pointing error correction of the local multipoint distributed system (LMDS). The beam pointing error caused by wind force can affect the performance of the local multipoint distributed system (LMDS). The correction device uses multi-beam planar array antenna to obtain the signal direction-of-arrival (DOA) of a base station and uses fuzzy basis function network (FBFN) algorithm, which includes thirteen normalized Gaussian membership functions and thirteen rules, to estimate the beam pointing error. The simulation results show that the presented FBFN processing device has better performance in transient response, convergence time and steady state value of the averaged square error than the conventional beam pointing error correction devices.Type: ApplicationFiled: August 26, 2002Publication date: October 9, 2003Applicant: Far Eastone Telecommunications Co., Ltd.Inventors: Jeich Mar, Lou Shing Lou
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Publication number: 20030186726Abstract: A base station for communicating with a mobile station, wherein the base station includes a first antenna which extends vertically relative to a reference plane, a second antenna which extends horizontally relative to the reference plane, a switching circuit which is electrically connected to the first and second antennas and which selectively outputs a signal from either one of the first and second antennas according to a control signal and a control circuit which supplies the control signal to the switching circuit in response to a signal received from the mobile station via at least one of the first and second antennas.Type: ApplicationFiled: February 12, 2003Publication date: October 2, 2003Inventor: Hidenori Akita
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Patent number: 6628235Abstract: A method for handing-off phased array antenna signals is provided. A phased array multiple antenna system receives and demodulates signals using one receiver. The phased array antennas are controlled electronically by an antenna controller. An antenna switch matrix in the antenna controller selects between signals from a handing-off antenna and a handed-to antenna. A phase comparator compares the two signals and produces a phase error signal proportional to the difference between the phase angles of the two signals. A negligible phase error difference is predetermined wherein antenna handoff can occur without causing loss of phase lock on the handed-to antenna signal. When the antenna controller signals a hand-off and the phase error equals the negligible phase error difference, a fast switch performs the hand-off. Power consumption is also controlled by requiring only one antenna to be powered “on” at a time.Type: GrantFiled: December 17, 2001Date of Patent: September 30, 2003Assignee: The Boeing CompanyInventor: Dennis Wight
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Patent number: 6628733Abstract: Signals from antennas A and B are alternately switched by an antenna switch at a predetermined rate. Then, the signals from the antennas A and B are alternately input to a wireless receiving unit. The wireless receiving unit orthogonal-signal-detects the signals received by the antennas A and B, and inputs the detected signals to a branch selecting unit. The branch selecting unit extracts only the signals from either of the antennas from the signals obtained from the antennas A and B, which are alternately arranged in time series, and transmits the extracted signals to a matched filter. A searcher obtains despreading timings from correlation values, and stores the obtained timings in two memories. The searcher obtains despreading timings with large correlation values, and transmits the timings to a despreading unit to perform RAKE reception.Type: GrantFiled: November 10, 1999Date of Patent: September 30, 2003Assignee: Fujitsu LimitedInventors: Norio Tomiyoshi, Takushi Mikami, Yoshinobu Haga, Osamu Yamano
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Patent number: 6622013Abstract: Desired signal power detection sections 109 to 116 measure a signal power level from a communication partner received at respective antennas 101 to 108. Antenna set selection section 117 obtains a sum of signal power levels from the communication partner received at four antennas belonging to each of antenna sets A to D each composed of combined antennas selected in advance to form a predetermined radiation pattern, for each antenna set, and selects an antenna set with the sum being the highest. Switch 120 connects received signals only from antennas belonging to the selected antenna set to reception RF sections 121 to 124. Received signal inputted to respective reception RF sections 121 to 124 are converted into respective intermediate-frequency signals, combined in signal combining section 125, and demodulated in demodulation section 126 to be a desired signal.Type: GrantFiled: December 7, 1999Date of Patent: September 16, 2003Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Kenichi Miyoshi, Katsuhiko Hiramatsu
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Patent number: 6611677Abstract: A scanning antenna diversity system for motor vehicles having at least two antennas mounted in a multi-antenna installation, and connected to a switching logic circuit. The circuit has discrete switching positions, and a reversing position USmax. A receiver is coupled to logic circuitry for receiving a RF signal from one of switching positions or reversing position USmax. There is a diversity processor coupled to and controlled by receiver for producing a derived received signal from the RF signal, with diversity processor cyclically stepping the logic circuitry to another switching position during the presence of receiver interference. There is a maximum level indicator having its input coupled to the antennas, and having its output connected to the controllable logic circuitry for sensing the strongest actual levels of the antenna signals. Level indicator 39 continuously compares the received signals at antennas and activates the logic switching circuit in response to any interference.Type: GrantFiled: December 15, 1999Date of Patent: August 26, 2003Assignee: Fuba Automotive GmbH & Co., KGInventors: Heinz Lindenmeier, Jochen Hopf, Leopold Reiter
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Publication number: 20030125003Abstract: A vehicle radio receiver has a beamsteering control system with two signal paths. One signal path generates an audio signal in response to incoming radio signals. Another signal path generates a test signal in response to the incoming radio signals. The audio signal is adjusted in response to the test signal.Type: ApplicationFiled: December 28, 2001Publication date: July 3, 2003Inventors: J. William Whikehart, Darby Edward Hadley, John Elliott Whitecar
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Publication number: 20030125002Abstract: A method (100) is provided for transmitting a traffic signal with an adaptive antenna array of a base transceiver such that a subscriber unit utilizes a non-dedicated pilot transmitted from a reference antenna element for demodulation of the traffic signal. The method (100) comprises determining a channel impulse response from a plurality of antenna elements in operative communication with the base transceiver to a receive antenna of the subscriber unit (102).Type: ApplicationFiled: January 3, 2002Publication date: July 3, 2003Applicant: Motorola Inc.Inventor: R. Mark Harrison
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Publication number: 20030119468Abstract: An apparatus and method for improving the signal reception of a digital wireless receiver comprises a processing circuit for processing the preamble information of incoming signals, wherein a first predetermined portion of the preamble information is applied to a first antenna and a second predetermined portion of the preamble information is applied to a second antenna to produce a plurality of processed signals, such that the plurality of processed signals is compared to a predefined preamble sequence to obtain a mean-square error (MSE) for the respective antenna. Then, one of the first and second antennas with a lower MSE is selected to receive and process the incoming signals.Type: ApplicationFiled: December 21, 2001Publication date: June 26, 2003Applicant: Koninklijke Philips Electronics N.V.Inventors: Joseph Meehan, Sunghyun Choi
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Patent number: 6577353Abstract: In a system for optimizing television reception by a television receiver receiving a diversity of input signals from a plurality of antennas, one of a plurality of combiners and television tuners selects the strongest combination of input signals for viewing and another scans the various combinations of input signals searching for a combination significantly stronger than the combination being viewed. A plurality of multiplexers selects the output signal of one combiner and transmits the selected signal to one of the tuners. A signal evaluation module evaluates the strength of the combinations of input signals and compares the strength of each combination of input signals to the strength of the viewing signal, looking for a superior signal. A control processor controls the combination of input signals selected by the combiners and the combiner output signal selected by the multiplexers.Type: GrantFiled: October 21, 1999Date of Patent: June 10, 2003Assignee: General Electric CompanyInventors: Kenneth Brakeley Welles, II, Mark Lewis Grabb, John Erik Hershey
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Publication number: 20030104796Abstract: Disclosed are a system and a method for improving performance in an HDR (High Data Rate) wireless terminal utilizing diversity techniques. The wireless terminal comprises two transmission paths, one including a duplexer and the other bypassing the duplexer, and two reception paths, one including the duplexer and the other not including a duplexer and completely isolated from any transmission path. When the terminal is determined to be in an HDR mode, the transmission path including the duplexer and both reception paths are utilized. When the terminal is operating in a low data rate mode, the transmission path bypassing the duplexer and the reception path completely isolated from the transmission paths are utilized, resulting in lower minimum detectable signal, thus reducing current consumption in the wireless terminal.Type: ApplicationFiled: November 30, 2001Publication date: June 5, 2003Applicant: SAMSUNG ELECTRONICS CO., LTD.Inventor: Heung-Sik Yoon
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Patent number: 6574461Abstract: The present invention relates to a method for diversity selection for antenna paths in a radio receiver (R2; R3) comprising a plurality of antennas (A, B; N) and a selection switch (SW; SWI) for selecting one of said antennas, which method comprises the following steps: generation of average interference powers (AIA, AIB; AIN) of antenna signals received over a period of time to each of the antenna's (A, B; N); generation of carrier signal strength (CSA, CSB; CSN) of radio signals (RSA, RSB) received to each of the antenna's (A, B; N); selecting one of the antennas (A, B; N) in dependence of the best carrier signal strength (CSA, CSB; CSN) in relation to average interference signal strength (AIA, AIB, AIN).Type: GrantFiled: June 18, 1998Date of Patent: June 3, 2003Assignee: Telefonaktiebolaget LM Ericsson (publ)Inventor: Johan Sköld
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Patent number: 6571097Abstract: An adaptive antenna directivity control method and a system therefor is capable of reducing interference in an up-link and/or a down-link upon initiation of handoff to improve communication quality upon initiation of handoff to speed-up directivity control resulting in increasing of channel capacity. In the adaptive antenna directivity control method, a mobile station and base station to be connected with the mobile station in radio through an up-link and a down-link are governed by a supervisory station. Respective transmission signal or reception signal of a plurality of antenna elements of the base station are varied in amplitude and phase for combining in a particular orientation for establishing a directivity by a radiation pattern by combining.Type: GrantFiled: February 18, 2000Date of Patent: May 27, 2003Assignee: NEC CorporationInventor: Kenichi Takai
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Publication number: 20030092379Abstract: A first downlink transmission beam and a second downlink transmission beam is determined based on a received user-derived signal. The first downlink transmission beam is substantially uncorrelated with the second downlink transmission beam. The first downlink transmission beam is associated with a portion within a first sector. The second downlink transmission beam is associated with a portion within a second sector. A first signal is diversity encoded to produce a first diversity-encoded signal. A second signal is diversity encoded to produce a second diversity-encoded signal. The first diversity-encoded signal is sent over the first downlink transmission beam. The second diversity-encoded signal is sent over the second downlink transmission beam.Type: ApplicationFiled: November 15, 2001Publication date: May 15, 2003Inventors: Louis R. Brothers, John Cangeme, Alexander Flaig, Samuel J. MacMullan, H V Poor, Tandhoni S. Rao, Stuart C. Schwartz, Triveni N. Upadhyay
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Patent number: 6564044Abstract: The present invention reduces the degradation in performance of one or more radio signals that are co-transmitted with a first radio signal from the same transmitting antenna in the same frequency channel and received by the same antenna due to multipath or other shared interference, where the one or more radio signals can be separated from the first radio signal.Type: GrantFiled: November 10, 1999Date of Patent: May 13, 2003Inventor: Kenneth F. Rilling
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Patent number: 6556845Abstract: A multiplication circuit 152 multiplies signals, which are subjected to variable directional transmission, by weighting factors with respect to the respective antennas 101 to 103, and outputs the resultant to combining circuits 155 to 157, respectively. The signals input to the combining circuit 155 are combined and radio modulated by a radio section 104, and transmitted from the antenna 101. Whereby, in a case where variable directional transmission is performed with respect to only some terminal apparatuses, signals, which are subjected to no variable directional transmission, can be transmitted after spreading them from the respective antennas of an array antenna.Type: GrantFiled: May 8, 2000Date of Patent: April 29, 2003Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Minako Ide, Katsuhiko Hiramatsu
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Patent number: 6553214Abstract: A window glass antenna system for the reception of AM and FM radio broadcasts in an automobile includes an antenna grid applied to a window of a vehicle, that is electrically separate from a heater grid applied to the rear window. An antenna module connected to the vehicle window antenna grid is comprised of a low noise amplifier, matching, and overload protection circuits. The overload protection circuit is included between the antenna grid and the RF amplifier. When the received radio antenna signal is at the typical operating level of the amplifier, the overload protection circuit connects the output of the antenna grid to the RF amplifier. When the received signal is higher than the linear dynamic range of the amplifier the overload protection circuit provides linearity of the signal that is applied to the car radio. This process consists of two steps.Type: GrantFiled: May 5, 2000Date of Patent: April 22, 2003Assignee: Tenatronics LimitedInventors: Victor Rabinovich, Irina Rabinovich, Terrance R. Reardon
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Publication number: 20030060179Abstract: A DPRAM is placed in the RF path before the digital to analog converter, to provide dynamic path gain compensation to the digital signal prior to conversion to an analog signal. The DPRAM stores corrections to the signal to compensate for amplitude losses in the signal arising from heat and non-linearities. The DPRAM has two sets of identical addresses. A logic switch, alternately directs an input signal to one of the two sets of addresses. Pre-calculated signal values which compensate for path gain are stored in one of the two sets of addresses in the DPRAM. The signal input to the DPRAM is directed to the other block. The value of the signal input to the DPRAM will determine the address to which the new value can be found. It is this new value which is actually input to the DAC and from which an analog signal is created.Type: ApplicationFiled: August 2, 2002Publication date: March 27, 2003Applicant: Lucent Technologies, Inc.Inventors: Miguel Dajer, Edward Ellis Eibling, Mark Y. McKinnon
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Patent number: 6507732Abstract: A DPRAM is placed in the RF path before the digital to analog converter, to provide dynamic path gain compensation to the digital signal prior to conversion to an analog signal. The DPRAM stores corrections to the signal to compensate for amplitude losses in the signal arising from heat and non-linearities. The DPRAM has two sets of identical addresses. A logic switch, alternately directs an input signal to one of the two sets of addresses. Pre-calculated signal values which compensate for path gain are stored in one of the two sets of addresses in the DPRAM. The signal input to the DPRAM is directed to the other block. The value of the signal input to the DPRAM will determine the address to which the new value can be found. It is this new value which is actually input to the DAC and from which an analog signal is created.Type: GrantFiled: September 14, 1999Date of Patent: January 14, 2003Assignee: Lucent Technologies Inc.Inventors: Miguel Dajer, Edward Ellis Eibling, Mark Y. McKinnon
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Patent number: 6505037Abstract: A system adjusts a receiving device in response to sensing symbols. An automatic gain control is adjusted in response receiving a first symbol of a data unit from a first antenna. After adjusting the automatic gain control at least a second and a third symbol of the data unit are received, and in response thereto (1) a first energy of at least one of the second and third symbols is calculated, (2) a first frequency offset of at least one of the second and third symbols is calculated, and (3) a first temporal offset of at least one of the second and third symbols is calculated. The automatic gain control in response receiving a fourth symbol of the data unit from a second antenna is received.Type: GrantFiled: February 23, 2000Date of Patent: January 7, 2003Assignee: SHARP Laboratories of America, Inc.Inventor: Srinivas Kandala
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Patent number: 6501964Abstract: The invention relates to sub macro cellular layers of a wireless communications system. An object of wireless communications system design is to reduce the number of base station sites required by increasing their range and or capacity. The term, “capacity” is used herein to refer to any suitable measure which provides an indication of how many conventional mobile terminals or other terminals are able to communicate effectively with a given antenna arrangement. Macro base station sites for cellular systems are particularly expensive, both in terms of the equipment required and the need for a geographical site for each cell site where, inter alia, large structures are frequently employed where planning permission is required. The present invention seeks to provide a system and method for reducing the effects of adjacent channel interference, especially in 3G CDMA base stations.Type: GrantFiled: December 20, 1999Date of Patent: December 31, 2002Assignee: Nortel Networks LimitedInventors: John E. Hudson, Keith Russell Edwards, Paul Barton
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Patent number: 6498928Abstract: A radio reception apparatus receives signals from all directions through a plurality of directivities, and generates a delay profile to each directivity. The apparatus selects a path having the largest received signal among a plurality of delay profiles generated by suppressing interference signals after thus narrowing down directions.Type: GrantFiled: December 22, 2000Date of Patent: December 24, 2002Assignee: Matsushita Electric Industrial Co., Ltd.Inventor: Katsuhiko Hiramatsu
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Publication number: 20020183031Abstract: A wireless call system enables even a bedridden person to easily answer a visitor. The wireless call system has an outdoor unit (3) installed on the outside of an entrance of a structure having a door (13) lockable with an electronic lock (15), for calling a resident in the structure, and an indoor unit (9) connected to the outdoor unit (3) by radio, for informing the resident of the presence of a visitor upon receiving a signal from the outdoor unit (3) and allowing the resident to answer the visitor through the outdoor unit (3). The outdoor unit (3) has an image pickup unit (23) for picking up an image of the visitor making a call with the outdoor unit (3). The indoor unit (9) is portable and has a display (53) for displaying the visitor's image picked up by the image pickup unit (23) and control buttons (55) for unlocking the electronic lock (15) if necessary.Type: ApplicationFiled: August 22, 2001Publication date: December 5, 2002Applicant: Unirec Co., Ltd.Inventor: Junichi Yamagishi
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Patent number: 6487391Abstract: The present invention provides an improved receiver capable of receiving either a satellite broadcast signal or a cable TV signal associated with a TV. The inventive receiver comprises a first BPF for filtering received broadcast signals, a first local oscillator for generating a first oscillation signal, a first mixer for generating a first IF signal, a SAW filter producing a waveformed band signal, a second local oscillator, for generating a second and a third oscillation signal, a second mixer for generating a second and a third IF signal, a switching block for switching the second and the third IF signal, a second BPF for producing a baseband channel signal selected from the cable TV signal, a first LPF for producing a baseband I signal of satellite broadcast channel, a shifter for shifting a phase of the third IF signal, a third mixer for generating a phase-shifted third oscillation signal, and a second LPF for producing a baseband Q signal of satellite broadcast channel.Type: GrantFiled: April 23, 1998Date of Patent: November 26, 2002Assignee: Daewoo Electronics Co., Ltd.Inventor: Young-Rok Park
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Patent number: 6477359Abstract: This invention is an application of antenna diversity and two or more multi-channel radios, with a novel cooperative sharing strategy among the multi-channel radios, to aeronautical packet data communications and other communications. It offers the following benefits: enhanced data communications performance in a fading environment; enhanced data communications performance at long range; enhanced data communications performance in the presence of cochannel interference; extendable to an arbitrary number of cooperating peer radios; no single point of failure; no increase in pilot workload or change in operational procedures.Type: GrantFiled: May 4, 2001Date of Patent: November 5, 2002Inventors: Stephen B. Heppe, K. Prasad Nair, Steven Friedman
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Patent number: 6456830Abstract: In the conventional diversity reception, information included in each non-selected signal does not contribute to an improvement in the reliability of communications, and transmitting power has been dissipated to satisfy required communication quality. Owing to the setting of encoding in respective base stations to injection, signals each including the same contents, which are received by a mobile station, are used for increasing the reliability of communications without depending on the number of the signals which were capable of being received by the mobile station, to thereby reduce transmitting power for satisfying required communication quality.Type: GrantFiled: August 17, 2001Date of Patent: September 24, 2002Assignee: Hitachi, Ltd.Inventors: Atsushi Ogino, Hideya Suzuki, Tomoaki Ishifuji
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Patent number: 6453168Abstract: A spread spectrum position location communication system determines the position of a mobile master radio using a round-trip messaging scheme in which the time of arrive (TOA) of ranging messages is accurately determined to yield the range estimates required to calculate the position of the mobile radio via trilateration. The master radio transmits outbound ranging messages to plural reference radios which respond by transmitting reply ranging messages. Upon reception of the reply ranging message, the master radio determines the range to the reference radio from the signal propagation time calculated by subtracting the far-end turn around time from the round-trip elapsed time. Any combination of fixed or mobile radios of known positions can be used as the reference radios for another mobile radio in the system, thereby providing adaptability under varying transmission conditions.Type: GrantFiled: August 2, 1999Date of Patent: September 17, 2002Assignee: ITT Manufacturing Enterprises, IncInventors: Dennis D. McCrady, Lawrence J. Doyle, Howard Forstrom
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Patent number: 6452988Abstract: The invention provides an adaptive sensor array apparatus (100) incorporating a multielement antenna (12) for receiving radiation from a scene (‘S’) and generating signals (e) in response thereto and a processing unit (114) for processing the signals (e) to provide an output signal (y). The unit (114) comprises an adaptive weight computer (136) arranged to generate weighting vectors (w) which are used in the unit (114) to attenuate contributions to the output signal (y) arising from sources of jamming radiation in the scene and transmit contributions to the output signal (y) arising from wanted targets therein. The apparatus (100) incorporates a non-adaptive beamformer unit (132) for preconditioning the signals (e) before they are passed to the computer (136). Preconditioning the signals (e) enhances performance of the apparatus (100) relative to conventional adaptive sensor array apparatus (10).Type: GrantFiled: June 29, 1999Date of Patent: September 17, 2002Assignee: Qinetiq LimitedInventor: Stephen D. Hayward
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Publication number: 20020123370Abstract: In a radio network which employs adaptive antennas for transmission of data to mobiles methods and apparatus are provided for improving the reception of transmitted data. When a block is to be transmitted in a first beam of the antenna and the block contains information for the mobile in the second beam, a modulation and coding scheme is used for the transmission of the block such that the modulation and coding scheme provides greater protection to the portion of the block containing information for the mobile in the second beam. The use of greater protection for the portion of the block which includes information for the mobile in the second beam increases the probability that the mobile in the second beam can receive and correctly decode the information intended for the mobile in the second beam in the block.Type: ApplicationFiled: March 2, 2001Publication date: September 5, 2002Inventors: Magnus Berg, Hakan Eriksson, Lars-Goran Lund, Sven Ekemark
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Patent number: 6445910Abstract: A radio diversity method in which a first received signal is received by a first antenna and a second received signal is received by a second antenna. The first received signal and the second received signal are converted from an analog format to a digital format. Digital signal values are in each case detected, with quality levels being defined in each case for the digital signal values. An evaluation device evaluates the quality levels and, depending on the evaluation result, passes on only portions of the digital signal values for subsequent combination. This reduces the data rate that needs to be transmitted, for example, during a soft hand over.Type: GrantFiled: July 28, 1999Date of Patent: September 3, 2002Assignee: Siemens AktiengesellschaftInventor: Stefan Oestreich
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Publication number: 20020111149Abstract: The following are provided a plurality of antennas provided- correspondingly to a plurality of radio communication systems, a plurality of processing circuits whose one ends are connected to the antennas to apply processings including amplification and frequency conversion to signals received from a corresponding antenna input to the above one ends or signals to be transmitted to a corresponding antenna input to the other ends of the circuits, an input/ output terminal which outputs a reception signal to an external unit or inputs a transmission signal from the external unit, and a unit connected between the processing circuits and the input/output terminal to couple reception signals output from the processing circuits or distribute transmission signals input from the input/output terminal to the processing circuits.Type: ApplicationFiled: February 5, 2002Publication date: August 15, 2002Inventor: Hiroki Shoki
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Patent number: 6430404Abstract: A scanning antenna diversity system for motor vehicles having at least two antennas disposed in a multi-antenna installation. The diversity system also contains a controllable logic circuitry, and a receiver for receiving a signal from the antennas. Connected to the receiver is a diversity processor controlled by the receiver, for stepping the logic circuitry to another switching position during the presence of reception interference. This occurs during the shortest possible comparison times, which are initiated in cyclic repetition upon expiration of a longer time interval by level comparison circuitry for detecting signals. In this case, the level comparison circuitry determines a maximum level switching position associated with the greater actual received signal in an actual receive situation. Thus, the level comparison time is selected sufficiently short so that the reception is not audibly impaired by the level comparison time.Type: GrantFiled: October 6, 1999Date of Patent: August 6, 2002Assignee: Fuba Automotive GmbH & Co. KGInventors: Heinz Lindenmeier, Jochen Hopf, Leopold Reiter
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Patent number: 6430421Abstract: The invention relates to an adaptive radio system that includes a plurality of mobile stations and at least one base station. In the radio system, at least the base station includes a plurality of independent transmitting and receiving branches to transfer signals between the base station and mobile stations. The radio system is according to the invention characterized in that it additionally includes means (401, 402) for connecting said transmitting branches and receiving branches in parallel and for numerical, dynamic assigning thereof to transfer of a single signal. The invention further relates to a method for assigning transmitting and receiving branches in a radio system.Type: GrantFiled: February 17, 2000Date of Patent: August 6, 2002Assignee: Nokia Networks OyInventors: Matti Kiiski, Ilkka Keskitalo
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Patent number: 6421543Abstract: A cellular radiotelephone base station communicates with cellular radiotelephones by receiving cellular radiotelephone communications energy from cellular radiotelephones on an antenna array, processing the received communications energy to produce at least three processed radiotelephone communications signals representing communications energy received from a coverage sector, and selecting at least two of the processed signals for decoding in a conventional decoder. Preferably, the selected signals are the processed signals having the highest power or signal quality.Type: GrantFiled: January 29, 1996Date of Patent: July 16, 2002Assignee: Ericsson Inc.Inventor: Karl J. Molnar
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Patent number: 6415141Abstract: A diversify receiver comprises an antenna selector for selecting signals received by diversity antennas. Detection circuitry detects respective strengths of the selected signals and produces first and second strength indication signals. A mode selector is provided for selecting a reference threshold or the second strength indication signal. A comparator compares the output of the mode selector with the first strength indication signal. The mode selector is controlled to select the reference threshold so that the first strength indication signal is compared with the reference threshold and then to select the second strength indication signal in response to a first output signal of the comparator indicating that the first strength indication signal is higher than the reference threshold, so that the first strength indication signal is compared with the second strength indication signal.Type: GrantFiled: December 17, 1999Date of Patent: July 2, 2002Assignee: NEC CorporationInventors: Yoshikazu Kakura, Tomoki Osawa
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Patent number: 6408169Abstract: The present invention relates to a base station of a radio system whose antenna means (11) include: means (6 to 8) for receiving signals associated with the same logical channel by at least two antenna beams (1 to 4), measuring means (8) for measuring the signal level of the signals received by the antenna beams, and control means (8) for selecting one or more antenna beams (1 to 4) and for supplying the signals of the selected antenna beam to a receiver unit (5) of the base station (BTS1). In order that the best possible signal would be definitely transmitted to the base station, the base station (BTS1) comprises means for measuring the quality of the signals and for generating a quality signal (BER) and for supplying it to the control means (8), and the control means (8) are arranged to select an antenna beam (1 to 4) on the basis of the signal level measured by the measuring means and the quality signal (BER) supplied to the control means.Type: GrantFiled: November 20, 1998Date of Patent: June 18, 2002Assignee: Nokia Telecommunications OyInventor: Jorma Pallonen
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Patent number: 6400704Abstract: A first sector cell is set as an object for measurement (S101). Reception levels in each time slot in the number of TDMA-TDD frames is measured for the object cell (S102) and for all the cells (S103 and S105). The results of the measurement of a specific sector cell are added to the results of the measurement of a sector cell opposite the specific sector cell, and time slots in which control channels can be placed are extracted for each sector cell (S106 to S108). TDMA-TDD frames are then allocated such that the control channels of each sector cell coincide with time slots in which control channels can be placed (S109). In this way, control channels are placed in time slots such that a base station having a sector cell structure avoids interference from the same frequency.Type: GrantFiled: December 26, 2000Date of Patent: June 4, 2002Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Yuko Mikuni, Takashi Kawabata, Norihiko Toyota
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Patent number: 6397083Abstract: Weighting coefficients for a phased array antenna are iteratively refined to optimal values by a ‘bootstrapped’ process that starts with a coarse set of weighting coefficients, to which received signals are subjected, to produce a first set of signal estimates. These estimates and the received signals are iteratively processed a prescribed number of times to refine the weighting coefficients, such that the gain and/or nulls of antenna's directivity pattern will maximize the signal to noise ratio. Such improved functionality is particularly useful in association with the phased array antenna of a base station of a time division multiple access (TDMA) cellular communication system, where it is necessary to cancel interference from co-channel users located in cells adjacent to the cell containing a desired user and the base station.Type: GrantFiled: February 13, 2001Date of Patent: May 28, 2002Assignee: Harris CorporationInventors: Gayle Patrick Martin, Steven D. Halford, John C. Henry, III
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Publication number: 20020058488Abstract: A receiver device for receiving incoming radio waves by using a plurality of antennas, which is capable of improving the maximum input sensitivity is provided. In the receiver device, a switching unit switches to an antenna having the lower antenna gain as a new receiving antenna on the precondition that when receiving incoming radio waves by one particular antenna currently set as the receiving antenna, if a reception level of this particular antenna becomes a level close to the maximum input sensitivity of a signal processing unit, then the reception condition is satisfactory. Consequently, it is possible to improve the maximum input sensitivity and forestall the occurrence of waveform distortion and the like.Type: ApplicationFiled: November 16, 2001Publication date: May 16, 2002Applicant: Pioneer CorporationInventor: Yutaka Miyahara
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Publication number: 20020022463Abstract: In mobile communication systems employing the CDMA method, the communication quality is acquired from the CDMA pilot channel. A communication quality acquisition apparatus comprises a delay profile acquisition unit comprising a control unit, synchronization unit and measurement unit, in addition to a data storage unit. The communication quality is measured by the synchronization unit and the measurement unit which are alternatively controlled by the control unit. When the communication quality is acquired through the CDMA pilot channel, the data acquisition efficiency can be significantly raised.Type: ApplicationFiled: April 4, 2001Publication date: February 21, 2002Inventors: Shinichi Mori, Tetsuro Imai, Yoshihiro Ishikawa, Mikio Iwamura
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Patent number: 6347220Abstract: In a CDMA wireless base station, signals that have been received by a plurality antenna elements of an array antenna on the receiving side are subjected to beam forming by a reception beam former to electrically form a plurality of uplink beams. Reception is carried out based upon the optimum beam (e.g., the beam for which the power is maximum) among the plurality of uplink beams. A transmission beam former for subjecting a transmission signal to beam forming is provided. Based upon whether an uplink reception signal is present or not, a controller performs control so as to carry out downlink beam forming, thereby forming a downlink transmission beam in a direction identical with that of the optimum uplink reception beam, or in such a manner that downlink beam forming is not carried out.Type: GrantFiled: August 31, 1998Date of Patent: February 12, 2002Assignee: Fujitsu LimitedInventors: Yoshinori Tanaka, Shuji Kobayakawa, Masafumi Tsutsui
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Patent number: 6345188Abstract: An apparatus and method of steering a signal from a base station is disclosed. The base station comprises one or more antenna arrays, one or more channel units, the channel units comprising means for phasing the signal to be transmitted and received in such a way that the gain from the antenna array is greatest in a specified direction. Further, the base station includes means for distinguishing connection quality information from information received from the mobile station. In order to improve the spectral efficiency and the connection quality, the channel unit comprises means for searching for the incoming directions and delays of the received signal components, and means for controlling the phasing means of the signal transmitted to the mobile on the basis of the information and the connection quality information received from the mobile station.Type: GrantFiled: November 14, 1997Date of Patent: February 5, 2002Assignee: Nokia Telecommunications OyInventors: Ilkka Keskitalo, Peter Muszynski, Jaana Laiho-Steffens
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Publication number: 20020004375Abstract: An antenna diversity receiver comprises a zero-IF receiver connected to two antennas (102a, 102b) via switches (532,534). Simultaneous measurement of signal qualities from both antennas is possible by routing signals from the first antenna (102a) via a first mixer (106) and channel filter (116) and routing signals from the second antenna (102b) via a second mixer (108) and channel filter (118). A diversity controller (536) compares the signal qualities received from the antennas (102a,102b) during a data preamble to select a preferred antenna, then adjusts the switches (532,534) to route the signals from the preferred antenna to both input mixers (106,108). The amplifier (104a,104b) connected to the deselected antenna may be switched off during data reception, thereby minimizing extra power consumption.Type: ApplicationFiled: June 28, 2001Publication date: January 10, 2002Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.Inventors: Adrian G. Spencer, Robert J. Davies